Agilent 66311A User Manual

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66311A Mobile Communications DC Source User's Guide 5962-8272

May 1998

Title & Document Type:

Manual Part Number:

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HP References in this Manual

This manual may contain references to HP or Hewlett-Packard. Please note that HewlettPackard's former test and measurement, semiconductor products and chemical analysis businesses are now part of Agilent Technologies. We have made no changes to this manual copy. The HP XXXX referred to in this document is now the Agilent XXXX. For example, model number HP8648A is now model number Agilent 8648A.

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USER’S GUIDE

HP Model 66311A

Mobile Communications

DC Source

For instruments with Serial Numbers:

HP 66311A: US38180101 and up

HP Part No. 5962-8272

Microfiche No. 5962-8273

Printed in USA: May 1998

Safety Summary

The following general safety precautions must be observed during all phases of operation of this instrument. Failure to comply with these precautions or with specific warnings elsewhere in this manual violates safety standards of design, manufacture, and intended use of the instrument. Hewlett-Packard Company assumes no liability for the customer's failure to comply with these requirements.

GENERAL

This product is a Safety Class 1 instrument (provided with a protective earth terminal). The protective features of this product may be impaired if it is used in a manner not specified in the operation instructions.

Any LEDs used in this product are Class 1 LEDs as per IEC 825-1.

ENVIRONMENTAL CONDITIONS

This instrument is intended for indoor use in an installation category II, pollution degree 2 environment. It is designed to operate at a maximum relative humidity of 95% and at altitudes of up to 2000 meters. Refer to the specifications tables for the ac mains voltage requirements and ambient operating temperature range.

BEFORE APPLYING POWER

Verify that the product is set to match the available line voltage, the correct fuse is installed, and all safety precautions are taken. Note the instrument's external markings described under "Safety Symbols".

GROUND THE INSTRUMENT

To minimize shock hazard, the instrument chassis and cover must be connected to an electrical ground. The instrument must be connected to the ac power mains through a grounded power cable, with the ground wire firmly connected to an electrical ground (safety ground) at the power outlet. Any interruption of the protective (grounding) conductor or disconnection of the protective earth terminal will cause a potential shock hazard that could result in personal injury.

ATTENTION: Un circuit de terre continu est essentiel en vue du fonctionnement sécuritaire de l'appareil. Ne jamais mettre l'appareil en marche lorsque le conducteur de mise … la terre est d‚branch‚.

FUSES

Only fuses with the required rated current, voltage, and specified type (normal blow, time delay, etc.) should be used. Do not use repaired fuses or short-circuited fuseholders. To do so could cause a shock or fire hazard.

DO NOT OPERATE IN AN EXPLOSIVE ATMOSPHERE

Do not operate the instrument in the presence of flammable gases or fumes.

DO NOT REMOVE THE INSTRUMENT COVER

Operating personnel must not remove instrument covers. Component replacement and internal adjustments must be made only by qualified service personnel.

Instruments that appear damaged or defective should be made inoperative and secured against unintended operation until they can be repaired by qualified service personnel.

iii

SAFETY SYMBOLS

Direct current

Alternating current

Both direct and alternating current

Three-phase alternating current

Earth (ground) terminal

Protective earth (ground) terminal

Frame or chassis terminal

Terminal is at earth potential. Used for measurement and control circuits designed to be operated with one terminal at earth potential.

Terminal for Neutral conductor on permanently installed equipment

Terminal for Line conductor on permanently installed equipment

On (supply)

Off (supply)

Standby (supply). Units with this symbol are not completely disconnected from ac mains when this switch is off. To completely disconnect the unit from ac mains, either disconnect the power cord or have a qualified electrician install an external switch.

WARNING

Caution

In position of a bi-stable push control

Out position of a bi-stable push control

Caution, risk of electric shock

Caution, hot surface

Caution (refer to accompanying documents)

The WARNING sign denotes a hazard. It calls attention to a procedure, practice, or the like, which, if not correctly performed or adhered to, could result in personal injury. Do not proceed beyond a WARNING sign until the indicated conditions are fully understood and met.

The CAUTION sign denotes a hazard. It calls attention to an operating procedure, or the like, which, if not correctly performed or adhered to, could result in damage to or destruction of part or all of the product. Do not proceed beyond a CAUTION sign until the indicated conditions are fully understood and met.

Declaration Page

DECLARATION OF CONFORMITY

according to ISO/IEC Guide 22 and EN 45014

Manufacturer's Name: Hewlett-Packard Company

Manufacturer's Address: 150 Green Pond Road Rockaway, New Jersey 07866 U.S.A.

declares that the Product

Product Name: a) Dynamic Measurement DC Source

b) System DC Power Supply

Model Number: a) HP 66311A, 66312A

b) HP 6612B, 6611C, 6612C, 6613C, 6614C

conforms to the following Product Specifications:

Safety: IEC 1010-1:1990+A1(1992) / EN 61010-1:1993

EMC: CISPR 11:1990 / EN 55011:1991 - Group 1 Class B IEC 801-2:1991 / EN 50082-1:1992 - 4 kV CD, 8 kV AD IEC 801-3:1984 / EN 50082-1:1992 - 3 V / m IEC 801-4:1988 / EN 50082-1:1992 - 0.5 kV Signal Lines 1 kV Power Lines

Supplementary Information:

The product herewith complies with the requirements of the Low Voltage Directive 73/23/EEC and the EMC Directive 89/336/EEC and carries the CE-marking accordingly.

New Jersey November, 1997 ______ Location Date Bruce Krueger / Quality Manager

European Contact: Your local Hewlett-Packard Sales and Service Office or Hewlett-Packard GmbH,

Department TRE, Herrenberger Strasse 130, D-71034 Boeblingen (FAX:+49-7031-14-3143)

Acoustic Noise Information

Herstellerbescheinigung

Diese Information steht im Zusammenhang mit den Anforderungen der Maschinenläminformationsverordnung vom 18 Januar 1991. * Schalldruckpegel Lp <70 dB(A) * Am Arbeitsplatz * Normaler Betrieb * Nach EN 27779 (Typprüfung).

Manufacturer's Declaration

This statement is provided to comply with the requirements of the German Sound Emission Directive, from 18 January 1991. * Sound Pressure Lp <70 dB(A) * At Operator Position * Normal Operation * According to EN 27779 (Type Test).

Printing History

The edition and current revision of this manual are indicated below. Reprints of this manual containing minor corrections and updates may have the same printing date. Revised editions are identified by a new printing date. A revised edition incorporates all new or corrected material since the previous printing date.

Changes to the manual occurring between revisions are covered by change sheets shipped with the manual. In some cases, the manual change applies only to specific instruments. Instructions provided on the change sheet will indicate if a particular change applies only to certain instruments.

This document contains proprietary information protected by copyright. All rights are reserved. No part of this document may be photocopied, reproduced, or translated into another language without the prior consent of Hewlett-Packard Company. The information contained in this document is subject to change without notice.

Table of Contents

Warranty Information ii Safety Summary iii Declaration Page v Acoustic Noise Information vi Printing History vi Table of Contents vii

1 - QUICK REFERENCE 1

HP 66311A Mobile Communication DC Source 1 The Front Panel - At a Glance 2 The Rear Panel - At a Glance 3 Instrument Configuration 3 Front Panel Number Entry 4 Front Panel Annunciators 5 Immediate Action Keys 5 Front Panel Menus - At a Glance 6 SCPI Programming Commands - At a Glance 7

2 - GENERAL INFORMATION 9

Document Orientation 9 Safety Considerations 10 Options and Accessories 10 Description 11

Capabilities 11 Front Panel Controls 11 Remote Programming 12 Output Characteristic 12

3 - INSTALLATION 15

Installation and Operating Checklist 15 Inspection 16

Damage 16 Packaging Material 16 Items Supplied 16 Cleaning 16

Location 17

Bench Operation 17 Rack Mounting 17

Input Connections 18

Connect the Power Cord 18

Output Connections 18

Current Ratings 18 Voltage Drops and Lead Resistance 19

Remote Sensing 19

Remote Sense Leads 20 Maintaining Stability while Remote Sensing 22 Output Compensation (High Mode/Low Mode) 22

Local Sensing 23 OVP Considerations 24 External Protection Connections 24 Digital I/O Connections 25

vii

Controller Connections 26

HP-IB Interface 26 RS-232 Interface 26

4 - TURN-ON CHECKOUT 29

Checkout Procedure 29 In Case of Trouble 31

Error Messages 31 Line Fuse 31

5 - FRONT PANEL OPERATION 33

Introduction 33 Front Panel Description 33 System Keys 35 Function Keys 36

Immediate Action Keys 36 Scrolling Keys 36 Metering Keys 37 Output Control Keys 38

Entry Keys 39 Examples of Front Panel Programming 40

1 - Setting the Output Voltage, Current, and Compensation 40 2 - Querying and Clearing Output Protection and Errors 41 3 – Making Front Panel Measurements 42 4 - Programming External Protection and the Digital Port Functions 44 5 - Setting the HP-IB Address and RS-232 Parameters 44 6 - Saving and Recalling Operating States 45

6 - INTRODUCTION TO PROGRAMMING 47

HP-IB Capabilities of the DC Source 47

HP-IB Address 47

RS-232 Capabilities of the DC Source 47

RS-232 Data Format 47 Baud Rate 47 RS-232 Flow Control 48

Introduction to SCPI 48

SCPI References 48 HP-IB References 48 Conventions Used in This Guide 49

Types of SCPI Commands 49

Multiple Commands in a Message 50 Moving Among Subsystems 50 Including Common Commands 51 Using Queries 51

Types of SCPI Messages 51

The Message Unit 52 Headers 52 Query Indicator 52 Message Unit Separator 52 Root Specifier 52 Message Terminator 52

SCPI Data Formats 53

Numerical Data Formats 53 Suffixes and Multipliers 53

viii

Response Data Types 53

SCPI Command Completion 54 Using Device Clear 54 RS-232 Troubleshooting 55 SCPI Conformance Information 55

SCPI Confirmed Commands 55 Non-SCPI Commands 55

7 - PROGRAMMING THE DC SOURCE 57

Introduction 57 Programming the Output 57

Power-on Initialization 57 Enabling the Output 57 Output Voltage 58 Output Current 58

Triggering Output Changes 59

SCPI Triggering Nomenclature 59 Output Trigger System Model 59 Setting the Voltage or Current Trigger Levels 59 Initiating the Output Trigger System 60 Generating Triggers 60

Making Measurements 61

Controlling Measurement Samples 61 Current Ranges and Measurement Detector 62 Window Functions 62 Voltage and Current Measurements 63 Pulse Measurements 63

Internally Triggered Measurements 65

SCPI Triggering Nomenclature 65 Measurement Trigger System Model 65 Initiating the Measurement Trigger System 66 Selecting the Measurement Trigger Source 66 Generating Measurement Triggers 66 Pre-event and Post-event Triggering 68

Programming the Status Registers 69

Power-On Conditions 69 Operation Status Group 71 Questionable Status Group 72 Standard Event Status Group 72 Status Byte Register 72 Determining the Cause of a Service Interrupt 73 Servicing Operation Status and Questionable Status Events 73 Monitoring Both Phases of a Status Transition 74

Inhibit/Fault Indicator 74

Remote Inhibit (RI) 74 Discrete Fault Indicator (DFI) 75 Using the Inhibit/Fault Port as a Digital I/O 75

8 - LANGUAGE DICTIONARY 77

Introduction 77

Subsystem Commands 77 Common Commands 81 Programming Parameters 81

Calibration Commands 82

CALibrate:CURRent 82 CALibrate:CURRent:MEASure:LOWRange 82 CALibrate:CURRent:MEASure:AC 82 CALibrate:CURRent:NEGative 82 CALibrate:DATA 83 CALibrate:LEVel 83 CALibrate:PASSword 83 CALibrate:SAVE 83 CALibrate:STATe 84 CALibrate:VOLTage 84 CALibrate:VOLTage:PROTection 84

Display Commands 85

DISPlay 85 DISPlay:MODE 85 DISPlay:TEXT 85

Measurement Commands 86

MEASure:ARRay:CURRent? FETCh:ARRay:CURRent? 86 MEASure:ARRay:VOLTage? FETCh:ARRay:VOLTage? 86 MEASure:CURRent? FETCh:CURRent? 87 MEASure:CURRent:ACDC? FETCh:CURRent:ACDC? 87 MEASure:CURRent:HIGH? FETCh:CURRent:HIGH? 87 MEASure:CURRent:LOW? FETCh:CURRent:LOW? 88 MEASure:CURRent:MAXimum? FETCh:CURRent: MAXimum? 88 MEASure:CURRent:MINimum? FETCh:CURRent:MINimum? 88 MEASure:VOLTage? FETCh:VOLTage? 89 MEASure:VOLTage:ACDC? FETCh:VOLTage:ACDC? 89 MEASure:VOLTage:HIGH? FETCh:VOLTage:HIGH? 89 MEASure:VOLTage:LOW? FETCh:VOLTage:LOW? 90 MEASure:VOLTage:MAXimum? FETCh:VOLTage:MAXimum? 90 MEASure:VOLTage:MINimum? FETCh:VOLTage:MINimum? 90 SENSe:CURRent:DETector 91 SENSe:CURRent:RANGe 91 SENSe:FUNCtion 92 SENSe:SWEep:OFFSet:POINts 92 SENSe:SWEep:POINts 92 SENSe:SWEep:TINTerval 92 SENSe:WINDow 93

Output Commands 94

OUTPut 94 OUTPut:DFI 94 OUTPut:DFI:SOURce 94 OUTPut:PON:STATe 95 OUTPut:PROTection:CLEar 95 OUTPut:PROTection:DELay 95 OUTPut:RI:MODE 96 OUTPut:TYPE 96 [SOURce:]CURRent 97 [SOURce:]CURRent:PROTection:STATe 97 [SOURce:]CURRent:TRIGger 97 [SOURce:]DIGital:DATA 98 [SOURce:]DIGital:FUNCtion 98 [SOURce:]VOLTage 98 [SOURce:]VOLTage:PROTection 99 [SOURce:]VOLTage:PROTection:STATe 99 [SOURce:]VOLTage:TRIGger 99

Status Commands 100

STATus:PRESet 100 STATus:OPERation? 100 STATus:OPERation:CONDition? 100 STATus:OPERation:ENABle 101 STATus:OPERation:NTR STATus:OPERation:PTR 101 STATus:QUEStionable? 102 STATus:QUEStionable:CONDition? 102 STATus:QUEStionable:ENABle 102 STATus:QUEStionable:NTR STATus:QUEStionable:PTR 103

System Commands 104

SYSTem:ERRor? 104 SYSTem:LANGuage 104 SYSTem:VERSion? 104 SYSTem:LOCal 105 SYSTem:REMote 105 SYSTem:RWLock 105

Trigger Commands 106

ABORt 106 INITiate:SEQuence INITiate:NAME 106 INITiate:CONTinuous:SEQuence1 INITiate:CONTinuous:NAME TRANsient 106 TRIGger 107 TRIGger:SOURce 107 TRIGger:SEQuence2 TRIGger:ACQuire 107 TRIGger:SEQuence2:COUNt:CURRent TRIGger:ACQuire:COUNt:CURRent 108 TRIGger:SEQuence2:COUNt:VOLTage TRIGger:ACQuire:COUNt:VOLTage 108 TRIGger:SEQuence2:HYSTeresis:CURRent TRIGger:ACQuire:HYSTeresis:CURRent 109 TRIGger:SEQuence2:HYSTeresis:VOLTage TRIGger:ACQuire:HYSTeresis:VOLTage 109 TRIGger:SEQuence2:LEVel:CURRent TRIGger:ACQuire:LEVel:CURRent 110 TRIGger:SEQuence2:LEVel:VOLTage TRIGger:ACQuire:LEVel:VOLTage 110 TRIGger:SEQuence2:SLOPe:CURRent TRIGger:ACQuire:SLOPe:CURRent 111 TRIGger:SEQuence2:SLOPe:VOLTage TRIGger:ACQuire:SLOPe:VOLTage 111 TRIGger:SEQuence2:SOURce TRIGger:ACQuire:SOURce 112 TRIGger:SEQuence1:DEFine TRIGger:SEQuence2:DEFine 112

Common Commands 113

*CLS 113 *ESE 113 *ESR? 114 *IDN? 114 *OPC 114 *OPT? 115 *PSC 115 *RCL 115 *RST 116 *SAV 116 *SRE 117 *STB? 117 *TRG 118 *TST? 118 *WAI 118

A - SPECIFICATIONS 119

Specifications 119 Supplemental Characteristics 120

B - VERIFICATION AND CALIBRATION 123

Introduction 123

Equipment Required 123 Test Setup 123

Performing the Verification Tests 124

Turn-On Checkout 125 Voltage Programming and Measurement Accuracy 125 Current Programming and Measurement Accuracy 125

Performing the Calibration Procedure 127

Front Panel Calibration Menu 128 Front Panel Calibration 128

Calibration Error Messages 131 Changing the Calibration Password 131 Calibration Over the HP-IB 131

C - ERROR MESSAGES 133

Error Number List 133

D - EXAMPLE PROGRAMS 137

Introduction 137

Assigning the HP-IB Address in Programs 137 National Instruments GP-IB Driver 137 HP BASIC 140 Pulse Measurements 141 DFI Programming Example 145

E - LINE VOLTAGE CONVERSION 147

Open the Unit 147 Configure the Power Transformer 147 Install the Correct Line Fuse 148 Close the Unit 148

F - COMPATIBILITY LANGUAGE 149

Introduction 149

INDEX 155

xii

Quick Reference

HP 66311A Mobile Communication DC Source

The HP 66311A is a 45 Watt, high performance dc power source that provides dynamic measurement and analysis of voltage and current waveforms. It is designed to simplify the testing of digital wireless communications products. For example, data acquired using its dynamic measurement capability can be used in determining the battery operating time. The 15 volt source and 5A peak current capability provides compatibility with a number of communications standards, inclunding: GSM, CDMA, TDMA, PCS, DECT, TERA, PHS, NADC, PHS, and others.

The combination of bench-top and system features in this dc source provide versatile solutions for your design and test requirements. Key features are summarized as follows:

Convenient bench-top features

♦ Up to 45 Watts output power

♦ Excellent transient voltage response characteristics

♦ Source and measurement capability of 5 amperes for up to 7 milliseconds

♦ Easy to use knob for voltage and current settings

♦ Highly visible vacuum-fluorescent front panel display

♦ Low power supply output noise of less than 6 mV peak-to-peak

♦ Current measurement resolution better than 1 microampere in the low range

♦ Current sinking up to 2.8 amperes

♦ Save and recall up to 4 instrument operating states

♦ I/O setup easily done from the front panel

Flexible system features

♦ HP-IB (IEEE-488) and RS-232 interfaces are standard

♦ SCPI (Standard Commands for Programmable Instruments) compatibility

♦ Output programming response times of less than 200 microseconds

♦ Dynamic current pulse measurement with pre- and post-trigger buffer capability

1 - Quick Reference

The Front Panel - At a Glance

1 A 14-character

display shows output measurements and programmed values.

CV CC

SYSTEM FUNCTION

LINE

Local

Off

2 Annunciators

indicate operating modes and status conditions.

66311A 0-15V/0-3A Mobile Communications DC Source

Unr Dis OCP

Error

Address

Save

Recall

Input

Meter

Protect

3 Rotary control sets

voltage, current, and menu parameters.

ÃÃÃÃ

Use and to set the resolution; then adjust the value with the knob.

Cal

Rmt Addr Err SRQ

Shift

Prot

890

Voltage

Current

Output

CalOCPProt Cir

Output

On/Off

4 Front panel output

connectors.

ÄÄÄÄ

ENTRY

Enter

Number

Enter

OUTPUT

50 VDC

Max

5 Turns the dc source

on and off.

6 System keys:

♦ return to Local

mode

♦ set the HP-IB

address

♦ set the RS-232

interface

♦ display SCPI

error codes

♦ save and recall

instrument states

♦ select

programming language.

7 Function keys:

♦ enable/disable

the output

♦ select metering

functions

♦ program voltage

and current

♦ set and clear

protection functions

cccc

♦ and

dddd

scroll through the front panel menu commands.

cccc

8 Entry keys:

♦ enter values ♦ increment or decrement

values

ÅÅÅÅ

♦ and

ÆÆÆÆ

select front panel menu parameters.

ÃÃÃÃ

♦ and

select a digit in the numeric entry field.

ÅÅÅÅ

ÄÄÄÄ

The Rear Panel - At a Glance

Quick Reference - 1

1 AC calibration switch

(see appendix B).

WARNING:

2 HP-IB (IEEE-488)

interface connector.

3 RS-232 interface

connector.

2 3 4

NO OPERATOR SERVICEABLE PARTS INSIDE, REFER SERVICING TO SERVICE TRAINED PERSONNEL.

RS 232

LINE

FUSE

AC - I CAL

| Normal

/ Hold to Cal

-S

50VDC MAX TO

FOR CONTINUED FIRE PROTECTION, USE SPECIFIED LINE FUSE

SENSE

Local

Remote

120V

250V

RATING

000VA

50/60 Hz

FUSE

4 INH/FLT (remote

INHibit / internal FauLT) connector. Connector plug is removable.

INH FLT

5 Output and Remote

sense connector.

5 6

6 Remote or Local

sense switch

7 8

7 Fuse holder 8 Power cord connector

(IEC 320) Connector plug is removable.

Instrument Configuration

Use the front panel Address key to configure the interface

Refer to “Front Panel Menus - At a Glance”

♦ Select either the HP-IB or RS-232 interface.

♦ Enter the HP-IB bus address.

♦ Configure the RS-232 baud rate, parity, and flow control.

♦ Select either the SCPI or COMPatibility programming language.

♦ Enable the optional HP 14575A remote front panel.

1 - Quick Reference

Front Panel Number Entry

Enter numbers from the front panel using one the following methods:

Use the arrow keys and knob to change voltage or current settings

NOTE: The output must be ON to see the displayed values change in Meter mode. With the

output enabled, this method changes the output voltage or current immediately.

Use the Function keys and knob to change the displayed settings

Use the arrow keys to edit individual digits in the displayed setting

Increments the flashing digit

Decrements the flashing digit

Moves the flashing digit to the right

Moves the flashing digit to the left

Enters the value when editing is complete

Use the Function keys and Entry keys to enter a new value

NOTE: If you make a mistake, use the Backspace key to delete the number, or press the Meter

key to return to meter mode.

Front Panel Annunciators

Quick Reference - 1

Unr

Dis

OCP

Prot

Cal

Shift

Rmt

Addr

Err

The output is operating in constant voltage mode.

The output is operating in constant current mode.

The output is unregulated.

The output is OFF. Press the Output On/Off key to turn the output on.

The over-current protection state is ON. Press the OCP key to turn over-current protection off.

Indicates that the output has been disabled by one of the protection features. Press the Prot Clear key to clear the protection condition.

Calibration mode is ON. Scroll to the Cal Off command and press the Enter key to exit the calibration mode.

The Shift key has been pressed.

The selected Remote programming interface (either HP-IB or RS-232) is active. Press the Local key to return the unit to front panel control.

The interface is addressed to talk or listen.

There is an error in the SCPI error queue. Press the Error key to view the error code.

SRQ

The interface is requesting service.

Immediate Action Keys

Output

A toggle switch that turns the output of the dc source on or off.

On/Off

Activates front panel control when the unit is in remote mode (unless a Lockout

Local

command is in effect).

Resets the protection circuit and allows the unit to return to its last programmed

Shift

A toggle switch that enables or disables overcurrent protection.

Prot Clr Shift

state.

OCP

1 - Quick Reference

Front Panel Menus - At a Glance

Address

Recall

Meter

Voltage

Current

Protect

Output

Shift Input

dddd

Save Shift Error Shift

dddd dddd dddd dddd dddd dddd dddd dddd dddd dddd

dddd dddd dddd dddd dddd dddd dddd dddd

OV Shift

dddd

Cal Shift

ADDRESS 7

INTF HPIB

BAUDRATE 300

PARITY NONE

FLOW NONE

LANG SCPI

REMOTE FP OFF

*RCL 0

*SAV 0

ERROR 0

12.000V 0.204A

12.500V MAX

1.000V MIN

12.330V HIGH

0.080V LOW

12.000V RMS

0.350A MAX

0.050A MIN

0.400A HIGH

0.012A LOW

0.210A RMS

VOLT 20.000

CURR 2.000

OC -- -- -- --

*RST PON:STATE RST PROT:DLY 0.08 RI LATCHING DFI OFF DFI:SOUR OFF PORT RIDFI DIGIO 7

TYPE:CAP LOW

VOLT:PROT 22

PROT:STAT ON

CURR:RANG HIGH

CURR:DET ACDC

TINT 46.8

POINT 2048

CAL ON

Use and to select parameters (table shows factory defaults). Use to exit any menu.

Sets the HP-IB Address

Selects an interface (HPIB or RS232)

Selects baud rate (300, 600, 1200, 2400, 4800, 9600)

Selects message parity (NONE, EVEN, ODD, MARK, SPACE)

Selects flow control (XON-XOFF, RTS-CTS, DTR-DSR, NONE)

Selects language (SCPI or COMP)

Enables or disables HP 14575A front panel interface (ON or OFF)

Recalls instrument state

Saves present instrument state

Displays errors in SCPI error queue

Measures output voltage and current Measures peak output voltage Measures minimum output voltage Measures the high level of a voltage pulse waveform Measures the low level of a voltage pulse waveform Measures rms voltage Measures peak output current Measures minimum output current Measures the high level of a current pulse waveform Measures the low level of a current pulse waveform

Measures rms current

Sets the output voltage

Sets the output current

Protection status (example shows overcurrent tripped)

Places the dc source in the factory-default state Select the power-on state command (RST or RCL0) Sets the output protection delay in seconds Sets the remote inhibit mode (LATCHING, LIVE, or OFF) Sets the discrete fault indicator state (ON or OFF) Selects the DFI source (QUES, OPER, ESB, RQS, or OFF) Sets the output port functions (RIDFI or DIGIO) Sets and reads the I/O port value (0 through 7)

Sets the output capacitance compensation (HIGH or LOW)

Sets the overvoltage protection level

Enables or disables overvoltage protection (ON or OFF)

Sets the current range (HIGH, LOW, or AUTO)

Sets the current measurement detector (ACDC or DC)

Sets the time interval for a front panel measurement in seconds

Sets the buffer size for a front panel measurement

Accesses calibration menu (See Appendix B).

MeterÅÅÅÅ ÆÆÆÆ

Quick Reference - 1

SCPI Programming Commands - At a Glance

NOTE: Some [optional] commands have been included for clarity. Refer to chapter 8 for a

complete description of all programming commands.

SENSe ABORt CALibrate

:CURRent [:POSitive] :FUNCtion “VOLT” | “CURR” :NEGative :SWEep :OFFSet :POINts <n> :MEASure :LOWRange :POINts <n> :AC :TINTerval <n> :DATA <n> [SOURce:] CURRent <n> :LEVel P1 | P2 | P3 | P4 :TRIGgered <n> :PASSword <n> :PROTection :STATe <bool> :SAVE DIGital :DATA <n> :STATe <bool> [, <n>] :FUNCtion RIDF | DIG :VOLTage [:DC] VOLTage <n> :PROTection :TRIGgered <n>

DISPlay

<bool> :STATe <bool> :MODE NORMal | TEXT :TEXT <display_string> :PRESet

INITiate

:SEQuence[1|2] :CONDition? :NAME TRANsient | ACQuire :ENABle <n> :CONTinuous :SEQuence[1], <bool> :NTRansition <n> :NAME TRANsient, <bool> :PTRansition <n>

MEASure | FETCh

:ARRay :CURRent? :CONDition? :VOLTage? :ENABle <n> [:CURRent] [:DC]? :NTRansition <n> :ACDC? :PTRansition <n> :HIGH? :LOW? :ERRor? :MAX? :LANGuage SCPI | COMPatibility :MIN? :VERSion? :VOLTage [:DC]? :LOCal :ACDC? :REMote :HIGH? :RWLock :LOW? :MAX? :SEQuence2| :ACQuire [:IMMediate] :MIN? :COUNt :CURRent <n>

OUTPut

:QUEStionable [:EVENt]?

:CURRent :RANGe <n> :DETector ACDC | DC

:PROTection <n>

STATus

:OPERation [:EVENt]?

SYSTem

TRIGger

:VOLTage <n>

General Information

Document Orientation

This manual describes the operation of the HP Model 66311A Mobile Communications DC Source. Unless otherwise noted, this model will be referred to by the description "dc source" throughout this manual.

The following Getting Started Map will help you find the information you need to complete the specific task that you want to accomplish. Refer to the table of contents or index of each guide for a complete list of the information contained within.

Getting Started Map

Task Where to find information

Quick Reference Section Installing the unit

Line voltage connections Computer connections Load connections Checking out the unit Verifying proper operation Using the front panel Calibrating the unit Using the front panel Front panel keys Front panel examples Using the programming interface HP-IB interface RS-232 interface

Programming the unit using SCPI (and COMPatibility) commands

SCPI commands SCPI programming examples SCPI language dictionary

Programming the unit using the HP VXIplug&play instrument driver

Installing the instrument driver Instrument driver functions C/C++ example programs Visual BASIC example programs LabVIEW example programs HP VEE example programs

Chapter 1 Chapter 2

Chapter 3

Chapter 5

Chapter 6

Chapters 7 and 8 for SCPI commands. Appendix D for SCPI examples Appendix F for COMPatibility commands

HP VXIplug&play installation sheet and on-line help

NOTE:

The driver must be installed on your pc to access the on-line information. Drivers for HP-UX are available on the web at www.hp.com/go/power

2 - General Information

Safety Considerations

This dc source is a Safety Class 1 instrument, which means it has a protective earth terminal. That terminal must be connected to earth ground through a power source equipped with a ground receptacle. Refer to the Safety Summary page at the beginning of this guide for general safety information. Before installation or operation, check the dc source and review this guide for safety warnings and instructions. Safety warnings for specific procedures are located at appropriate places in the guide.

Options and Accessories

Table 2-1. Options

Option Description

100

220

230

1CM1 Rack mount kit for one unit (HP p/n 5062-3972) AXS1 Rack mount kit for two side-by-side units of equal depth. Consists of:

8ZJ Delete instrument feet option J01 Output Compensation set to High Mode

Support rails are required when rack mounting units. Use E3663A support rails for HP rack cabinets,

and E3664A for non-HP rack cabinets.

0BN Service manual with extra operating manuals

87−106 Vac, 47−63 Hz

191−233 Vac, 47−63 Hz

207−253 Vac, 47−63 Hz

Lock-link kit (HP p/n 5061-9694) and Flange kit (HP p/n 5062-3974)

Table 2-2. Accessories

Item HP Part Number

HP-IB cables 1.0 meter (3.3 ft) HP 10833A

2.0 meters (6.6 ft) HP 10833B

4.0 meters (13.2 ft) HP 10833C

0.5 meters (1.6 ft) HP 10833D

RS-232 cable 9-pin F to 9-pin F, 2.5 meter, null modem/printer cable with one 9-pin M to 25-pin F adapter

RS-232 adapter kit - contains the following 4 adapters 9-pin M to 25-pin M for pc or printer 9-pin M to 25-pin M for pc or printer 9-pin M to 25-pin M for modem 9-pin M to 9-pin M for modem

Rack mount with slide - for two side-by-side units of different depths 5062-3996; 1494-0015

Rack mount - for two side by side units of different depths 5062-3996

Rack mount with slide - for one unit 5062-3996; 1494-0015;

Remote front panel - for viewing up to 6 remote HP 66311A units Includes an ac/dc adapter for powering up to 3 remote panels

HP 34398A

HP 34399A

5062-4022

HP 14575A

General Information - 2

Description

The HP 66311A Mobile Communications DC Source provides a stable, programmable dc source for testing digital wireless communications products. It integrates a highly accurate voltage and current meter with the capability to measure currents in the microampere range. The HP 66311A also has the ability to measure and characterize output voltage and current waveforms.

The HP 66311A can source and measure currents up to 5 amperes for up to 7 milliseconds. Note that the average current cannot exceed 3.0712 amps. If the unit attempts to draw current for longer than seven milliseconds, the current limit amplifier will limit the current to 3.0712 amps.

NOTE: To source up to 5 amperes of current for up to 7 milliseconds, the current limit must

be programmed for greater than 3 amperes (up to a maximum of 3.0712 A).

Capabilities

♦ Output Voltage and Current control with 12-bit programming resolution.

Current source capability up to 5 amperes for 7 milliseconds

♦ Extensive measurement capability:

dc voltage and current. rms and peak voltage and current. Current measurement capability up to approximately 7.0 amperes 16-bit measurement resolution (low range is accurate to less than 1 microampere). Triggered acquisition of digitized current and voltage waveforms

♦ Front panel control with 14-character vacuum fluorescent display, keypad, and rotary control for

voltage and current settings.

♦ Built-in HP-IB and RS-232 interface programming with SCPI command language.

♦ Non-volatile state storage and recall with SCPI command language.

♦ Over-voltage, over-current, over-temperature, and RI/DFI protection features.

♦ Extensive selftest, status reporting, and software calibration.

Front Panel Controls

The front panel has both rotary (RPG) and keypad controls for setting the output voltage and current. The panel display provides digital readouts of a number of output measurements. Annunciators display the operating status of the dc source. System keys let you perform system functions such as setting the HP-IB address and recalling operating states. Front panel Function keys access the dc source function menus. Front panel Entry keys let you select and enter parameter values.

Refer to chapter 5 for a complete description of the front panel controls.

2 - General Information

Remote Programming

NOTE: When shipped, all units are set to the SCPI programming language. The language setting

is saved in non-volatile memory. To change the programming language from SCPI to COMPatibility language, press the front panel COMP, then press

Address key, use d

d to scroll to the LANG command, press Æ

Enter. Refer to the chapters 6 through 8 for further information about

Æ to select

ÆÆ

remote programming.

The dc source may be remotely programmed via the HP-IB bus and/or from an RS-232 serial port. HP-IB programming is with SCPI commands (Standard Commands for Programmable Instruments), which make the dc source programs compatible with those of other HP-IB instruments. Dc source status registers allow remote monitoring of a wide variety of dc source operating conditions. A Compatibility language mode is also included to make the dc source compatible with the HP 6632A, 6633A, and 6634A Series dc power supplies (refer to appendix E). Note that the compatibility features of this unit are limited to the features that were originally available on HP 6632A, 6633A, and 6634A units.

Output Characteristic

The dc source's output characteristic is shown in the following figure. The output of the dc source may be adjusted to any value within the boundaries shown.

-2.8A

VSET

-1.2A

Output

Voltage

15V

ISET

Peak Current

capability for up

to 7 ms shown by dotted lines

Output Current

Figure 2-1. Dc Source Output Characteristic

General Information - 2

The dc source is capable of providing a constant dc output of 15 volts with up to 3 amperes of current. It is capable of sourcing peak currents of up to 5 amperes -- provided the peak current pulse does not exceed 7 milliseconds, and the average current requirement does not exceed 3 amperes. The peak current capability is illustrated by the dotted line in Figure 2-1.

The dc source can operate in either constant voltage (CV) or constant current (CC) over the rated output voltage and current. Figure 2-1 shows a single range − two quadrant capability. This means that the dc source is capable of sourcing as well as sinking current over the output voltage range from zero volts to the rated voltage. This negative current sinking capability provides fast downprogramming of the output of the dc source. The negative current is not programmable, and varies linearly from 1.2 amperes at the full rated voltage, to 2.8 amperes at zero output voltage.

The operating point of the unit is determined by the voltage setting, current setting, and the load resistance. In figure 2-1, operating point 1 is defined by the load line traversing the positive operating quadrant in the constant voltage region. Operating point 2 is defined by the load line traversing the positive operating quadrant in the constant current region.

NOTE: If you attempt to operate the dc source beyond its output ratings, the output of the unit

may become unregulated. This is indicated by the UNR annunciator on the front panel. The output may also become unregulated if the ac line voltage drops below the minimum rating specified in Appendix A.

Appendix A documents the dc source's specifications and supplemental characteristics.

Installation

Installation and Operating Checklist

Check the Output Compensation

 As shipped from the factory, the output compensation of the dc source is set to Low Mode. This lets the unit operate with phones having input capacitances from 0 to 12000 µF. For improved transient response in your test system, you may want to set the output compensation to High Mode (for phones having input capacitances from 5 to 12000 µF). Refer to “Output Compensation” in this chapter.

Check the Sense and Load Connections

 If you are remote sensing, is the sense switch on the back of the dc source in the Remote position? Remote sensing is recommended for most applications. Push the switch out for remote sensing.

Refer to “Remote Sensing” in this chapter.

 If you are remote sensing, are the + and −−−− sense leads connected ONLY at the test fixture and within 20 inches of the phone contacts? For best performance, the distance from sense lead termination

to the phone contacts should be as short as possible. Refer to “Lead Resistance” in this chapter.

 If you are using the front panel terminals, are the load leads twisted and less than 18 inches in length? When using the front panel terminals and not remote sensing, you must set the sense switch on

the back of the unit to the Local position. Refer to “Lead Resistance” and “Local Sensing” in this chapter.

Check the Operating Settings and Conditions

 Are you able to communicate remotely with the dc source? If not, check that the address setting and the programming language are set correctly. Refer to “HP-IB address” and “Language setting” in chapter 5.

 Is the Prot or Err annunciator on the front panel on? If yes, clear the fault condition before continuing. Refer to “Clearing Protection” in chapter 5.

 Is the Overvoltage circuit shutting the unit down? If yes, you can disable the overvoltage circuit. Refer to “Clearing Protection” in chapter 5.

 Are you measuring dynamic output currents? If yes, check that the current detector is set to ACDC. Refer to “Front Panel Measurements” in chapter 5.

 Are you measuring output currents under 20 mA? If yes, check that the current range is set to LOW. Refer to “Front Panel Measurements” in chapter 5.

 Are the front panel readings unstable? If yes, check that the front panel sampling rate is correct. Also check the setting of the output compensation. Refer to “Front Panel Measurements” in chapter 5 and “Output Compensation” in this chapter.

3 - Installation

Inspection

Damage

When you receive your dc source, inspect it for any obvious damage that may have occurred during shipment. If there is damage, notify the shipping carrier and the nearest HP Sales and Support Office immediately. The list of HP Sales and Support Offices is at the back of this guide. Warranty information is printed in the front of this guide.

Packaging Material

Until you have checked out the dc source, save the shipping carton and packing materials in case the unit has to be returned. If you return the dc source for service, attach a tag identifying the model number and the owner. Also include a brief description of the problem.

Items Supplied

The following user-replaceable items are included with your dc source. Some of these items are installed in the unit.

Table 3-1. Items Supplied

Item Part Number Description

Power Cord contact the nearest HP

Sales and Support

Office

Digital connector 1252-1488 4-terminal digital plug that connects to the back of the

Output connector 0360-2604 5-terminal plug that connects to the back of the unit.

Line Fuse 2110-0303

2110-0007

Feet 5041-8801 feet for bench mounting

User's Guide 5962-8272 Contains installation, checkout, and front panel

A power cord appropriate for your location.

unit.

2 A slow-blow for 100/120 Vac operation 1 A slow-blow for 220/230 Vac operation

information.

Cleaning

Use a dry cloth or one slightly dampened with water to clean the external case parts. Do not attempt to clean internally.

WARNING: To prevent electric shock, unplug the unit before cleaning.

Installation - 3

Location

The outline diagram in figure 3-1 gives the dimensions of your dc source. The dc source must be installed in a location that allows sufficient space at the sides and back of the unit for adequate air circulation (see Bench Operation).

Bench Operation

Do not block the fan exhaust at the rear of the unit.

A fan cools the dc source by drawing air in through the sides and exhausting it out the back. Minimum clearances for bench operation are 1 inch (25 mm) along the sides.

Rack Mounting

The dc source can be mounted in a standard 19-inch rack panel or cabinet. Table 2-1 documents the HP part numbers for the various rack mounting options that are available for the dc source. Installation instructions are included with each rack mount option.

NOTE: Support rails or an instrument shelf is required when rack mounting units.

Figure 3-1. Outline Diagram

3 - Installation

Input Connections

Connect the Power Cord

1. Unscrew the line fuse cap from the rear panel and verify that the fuse rating matches what is

specified on the FUSES label on the rear panel. Reinstall the fuse. (See table 3-1 for fuse part numbers.)

2. Connect the power cord to the IEC 320 connector on the rear of the unit. If the wrong power cord

was shipped with your unit, contact your nearest HP Sales and Support Office (refer to the list at the back of this guide) to obtain the correct cord.

Output Connections

Turn the unit off before connecting any wires.

The output connector has a termination for the + and − output, the + and − sense terminals, and an earth ground terminal. The 5-pin connector is removable and accepts wires sizes from AWG 22 to AWG 12. Disconnect the mating plug from the unit by pulling it straight back.

Front panel binding posts are provided as a convenience for bench operation. The front panel binding posts are paralleled with the rear panel + and − connections. Load wires that are connected to the front panel binding posts should be twisted and less than 18 inches in length. Before using the front panel binding posts, make sure that the sense switch on the back of the unit is set to Local.

NOTE: The front panel binding posts do not meet the noise, regulation, and transient response

specifications documented in Appendix A. The specifications documented in Appendix A apply only when measured at the rear terminal connections.

Current Ratings

Fire Hazard To satisfy safety requirements, load wires must be large enough not to overheat when

carrying the maximum short-circuit current of the dc source.

The following table lists the characteristics of AWG (American Wire Gage) copper wire.

Table 3-2. Ampacity and Resistance of Stranded Copper Conductors

AWG No. Maximum Ampacity (in

free air)

24 3.52 0.0843 0.0257 22 5.0 0.0531 0.0162 20 8.33 0.0331 0.0101 18 15.4 0.0210 0.00639 16 19.4 0.0132 0.00402 14 31.2 0.0083 0.00252 12 40 0.0052 0.00159

Resistance (at 20 deg. C)

Ω

ΩΩΩΩ/m

Ω/ft

ΩΩ

Installation - 3

Voltage Drops and Lead Resistance

To optimize the performance and transient response in your test system, please observe the following guidelines:

♦ Twist the load leads together and keep them as short as possible. The shorter the leads, the better the

performance.

♦ When remote sensing, twist the sense leads together but do not bundle them in with the load leads.

♦ Keep the total cable length to 18 inches or less when local sensing.

♦ Keep the total cable length to the load to 20 ft or less when remote sensing. (Note that the unit has

been tested with cable lengths of up to 40 feet.)

The load wires must also be of a diameter large enough to avoid excessive voltage drops due to the impedance of the wires. In general, if the wires are heavy enough to carry the maximum short circuit current without overheating, excessive voltage drops will not be a problem.

The maximum allowable value of load lead resistance is 4 ohms total (2 ohms per side). This may be further limited to a lower value, based on peak current loading, by the maximum allowable dc voltage drop of 8 volts total (4 volts per side) as specified for remote sense operation. To illustrate, for up to 2 amps peak, the maximum allowable resistance is 4 ohms total, resulting in a maximum voltage drop of up to 8 volts. For 4 amps peak the maximum allowable resistance is 2 ohms total, again resulting in a maximum allowable voltage drop of up to 8 volts.

In addition to keeping dc resistance low, you also need to minimize the total impedance. For higher slew rate currents (0.2 to 0.3 amps/µs) and long wiring lengths (10 to 20 ft.) the inductance can have as much effect as the resistance. To minimize inductance, twist the load leads. The inductance will be on the order of 0.15 µH/ft if twisted, and 0.4 µH/ft if untwisted. In addition to lowering the inductance, twisting the leads will reduce noise pick up. If you are using remote sense leads, connect these as a second twisted pair. Do not twist or bundle them with the load leads.

NOTE: The use of relays between the dc source and the phone also increases impedance. Low

resistance relays will improve system performance.

Remote Sensing

Turn the unit off before connecting any wires.

With the Remote/Local switch in the Remote position, the dc source regulates the output voltage at the output terminals on the back of the unit. External sense terminals are available on the back of the unit that allow the output voltages to be sensed at the load, compensating for impedance losses in the load wiring.

NOTE: For the majority of phone applications, remote sensing is highly recommended. In manu

cases remote sensing must be used to ensure stability and optimize transient response.

3 - Installation

The output connector accepts wires sizes from AWG 22 to AWG 12. Disconnect the mating plug to make your wiring connections. When the sense wire connections are complete, set the Remote/Local switch on the back of the unit to Remote (switch is out). Remote sensing is illustrated in figure 3-2.

HP 66311A OUTPUT CONNECTOR

-S - + +S

TWIST PAIR

SENSE

Local

Remote

TWIST LEADS

SENSE

SWITCH OUT

WIRE RESISTANCE

LOAD

Figure 3-2. Remote Sense Connections

Remote Sense Leads

Testing has verified stable performance with the sense leads connected up to 20 inches from the phone. However, for optimum performance, connect the sense leads as close as possible to the phone under test. To minimize inductance, connect the sense leads as a separate twisted pair.

The sense leads are part of the dc source's feedback path and must be kept at a low resistance (less than several ohms) to maintain optimal performance. Connect the sense leads carefully so that they do not become open-circuited. If the sense leads are left unconnected or become open during operation, the dc source will regulate at the output terminals, resulting in a 3% to 5% increase in output over the programmed value. Shorting the sense leads forces the dc source to its maximum voltage, which will trip the overvoltage protection circuit if it is enabled.

Connect the remote sense leads only to the remote sense connections at the output connector and at the location on the test fixture where you want to sense the output voltage. There must be not be any continuity from the sense leads to earth ground or from the sense leads to the output leads other than at the test fixture. To check for continuity, unplug the output connector from the dc source and temporarily disconnect the sense leads from the phone contacts. Use an ohmmeter and check for continuity between the sense and load leads and between the sense leads and ground. Poor transient response will result if continuity exists.

Figure 3-3 shows how to connect remote sense leads and load leads when external disconnect relays are included in the load path.

Installation - 3

NOTE: In this arrangement, the output of the unit should be programmed OFF before the relays

are switched. This is because if the load leads are opened before the sense leads, the overvoltage protection circuit will trip if it is enabled.

HP 66311A OUTPUT CONNECTOR

-S - + +S

TWIST PAIR

SENSE

Local

Remote

TWIST LEADS

SENSE

SWITCH OUT

LOAD

WIRE RESISTANCE

DISCONNECT RELAYS

Figure 3-3. Remote Sense Connections with External Relays

Figure 3-4 shows how to connect remote sense leads when using a removable test fixture. Note that in this configuration, the wires in the part of the test fixture where the phone is located must be less than 20 inches in length. This is for stability ase well as for the fact that the remote sense leads cannot compensate for the voltage drop in this part of the test fixture.

HP 66311A OUTPUT CONNECTOR

-S - + +S

TWIST PAIR

SENSE

Local

Remote

TWIST LEADS

SENSE

SWITCH OUT

LENGTH

MUST BE

UNDER 20

INCHES

LOAD

WIRE RESISTANCE

FIXTURE

CONNECTIONS

TWIST LEADS

Figure 3-4. Remote Sense Connections with Test Fixture

3 - Installation

The overvoltage protection circuit senses voltage near the output terminals, not at the load. Therefore the signal sensed by the OVP circuit can be significantly higher than the actual voltage at the load. When using remote sensing, you must program the OVP trip voltage high enough to compensate for the voltage drop between the output terminals and the load. Also, if the sum of the programmed voltage and the loadlead drop exceeds the maximum voltage rating of the dc source, this may also trip the OV protection circuit. Refer to OVP considerations for more information.

Maintaining Stability while Remote Sensing

The remote sense bandwidth and slew rate of standard dc power sources are adequate for compensating for load lead voltage drop for slow to moderate rates of load changes. However, the high pulsed current draw of digital cellular phones presents a challenge to standard dc power sources operating in remote sense mode. Their bandwidth and slew rate are not adequate for dealing with the 0.05 to 0.2 amp/µs slew rates imposed by these devices. A large voltage transient occurs at the load, due to the inability of the dc source to keep up with the rate of load change.

In remote sense mode, the HP 66311A effectively compensates for load lead voltage drops resulting from very high slew rate load current transitions and thus keeps the remotely sensed output voltage at a constant level. For 0.05 amp/µs to 0.2 amp/µs slew rate loading in typical test applications, the transient voltage is reduced more than an order of magnitude over that of a standard dc source.

Output Compensation (High Mode/Low Mode)

High bandwidth performance and stability are achieved by using a software-switchable output compensation circuit. This compensation circuit sets the remote sensing response of the dc source for the capacitance of the cellular phones. The compensation function is set using either the front panel TYPE:CAP command located in the Output menu (see chapter 5), or the OUTput:TYPE[:CAPacitance] SCPI command as explained in chapter 8. The circuit covers the following capacitance ranges:

♦ Low Mode: 0 to 12,000 µF ♦ High Mode: 5 µF to 12,000 µF

The HP 66311A is shipped from the factory with the output compensation set to Low Mode. If you do not know the input capacitance of the phone that you are testing, leave the input capacitance set to Low Mode initially. This is because in Low Mode, the output of the dc source will be stable when testing cellular phones that have virtually any input capacitance (from 0 µF to 12,000 µF). Low mode however, has a slower transient response (see appendix A).

The High Mode output compensation setting provides faster transient response performance for most phones. (Most phones have input capacitances greater than 5 µF.) In High Mode however, the operation of the dc source may be momentarily unstable with phones that have input capacitances less than 5 µF.

If you are testing phones in High Mode and want to determine if the input capacitance of your phone is less than 5 µF, perform the following test.

NOTE: It is important that this test is done with the dc source installed in the test system where it

will be used, since system stability is also dependent on wiring and the phone impedance.

Installation - 3

1. Connect the phone to the dc source and place it in standby mode.

2. Check the last two digits of the voltage reading on the front panel of the dc source.

3. If the last two digits are fluctuating, it is an indication that the phone capacitance may be less than

5 µF and the dc source is momentarily unstable.

4. Place the output compensation of the dc source in Low Mode.

5. If the last two digits of the voltage reading are now stable, your phone has an input capacitance less

than 5 µF.

Local Sensing

Remote sensing is preferred when connecting the output of the dc source to the load. However, you may also connect the output to the load without remote sensing provided that you observe the following:

♦ Keep load leads as short as possible. Load leads cannot exceed 18 inches (per side) when local

sensing.

♦ Bundle or twist the leads tightly together to minimize inductance.

♦ Set the Sense switch on the back of the unit to Local by pushing it in.

NOTE: You must set the sense switch to the Local setting if you are connecting the load leads to

the front panel binding posts and are not using the remote sense connections.

HP 66311A OUTPUT CONNECTOR

SENSE

Local

Remote

TWIST LEADS

SENSE

SWITCH IN

WIRE RESISTANCE

LOAD

EACH LEAD MUST

BE LESS THAN 20

INCHES IN LENGTH

-S - + +S

Figure 3-5. Local Sensing

3 - Installation

OVP Considerations

CAUTION: Disabling the OVP protection circuit may cause excessive output voltages, such as can

occur if remote sense leads are shorted, to damage the equipment under test.

The dc source is shipped from the factory with its overvoltage protection circuit enabled. You can disable the OVP circuit using either the front panel VOLT PROT command located in the OV menu, or the VOLTage:PROTection:STATe SCPI command as explained in chapter 8.

The OVP circuit contains a crowbar SCR, which effectively shorts the output of the dc source whenever the OVP trips. However, if an external current source such as a battery is connected across the output and the OVP is inadvertently triggered, the SCR will continuously sink a large current from the battery, possibly damaging the dc source.

To avoid this, either disable the OVP circuit or program it to its maximum value to prevent it from inadvertently tripping. Additionally, you can connect an external protection diode in series with the output of the dc source. Connect the anode of the diode to the + output terminal.

The OVP circuit's SCR crowbar has also been designed to discharge capacitances up to a specific limit, which is 50,000 µF. If your load capacitance approaches this limit, it is recommended that you do not intentionally trip the OVP and discharge the capacitance through the SCR as part of your normal testing procedure, as this may lead to long-term failure of some components.

External Protection Connections

This rear panel connector, has a fault output port and an inhibit input port. The fault (FLT) output, also referred to as the DFI (discrete fault indicator) signal in the front panel and SCPI commands, is an open collector circuit that pulls the positive output low with respect to the negative (chassis-referenced) common. The high impedance inhibit (INH) input, also referred to as the RI (remote inhibit) signal in the front panel and SCPI commands, is used to shut down the dc source output whenever the INH + is pulled low with respect to the INH (chassis-referenced) common.

The connector accepts wires sizes from AWG 22 to AWG 12. Disconnect the mating plug to make your wire connections.

NOTE: It is good engineering practice to twist and shield all signal wires to and from the digital

connectors. If shielded wire is used, connect only one end of the shield to chassis ground to prevent ground loops.

Figure 3-6 shows how you can connect the FLT/INH circuits of the dc source.

NOTE: Connectors

are removable

Installation - 3

INH FLT

. . . .

+ - +

INH Input

INH Common

) INH Example with One Unit

Switch

(Normally

Open)

. . . .

+ - +

INH Input

B) FLT Example with Multiple Units

FLT Output

Figure 3-6. FLT/INH Examples

In example A, the INH input connects to a switch that shorts the Inhibit pin (+) to common whenever it is necessary to disable output of the unit. This activates the remote inhibit (RI) circuit, which turns off the dc output. The front panel Prot annunciator comes on and the RI bit is set in the Questionable Status Event register. To re-enable the unit, first open the connection between pins INH + and common and then clear the protection circuit. This can be done either from the front panel or over the HP-IB/RS-232.

In example B, the FLT output of one unit is connected to the INH input of another unit. A fault condition in one of the units will disable all of them without intervention either by the controller or external circuitry. The controller can be made aware of the fault via a service request (SRQ) generated by the Questionable Status summary bit. Note that the FLT output can also be used to drive an external relay circuit or signal other devices whenever a user-definable fault occurs.

Digital I/O Connections

As shown in Table 3-3 and Figure 3-7, the FLT/INH connector can also be configured as a digital I/O port. Information on programming the digital I/O port is found in chapter 5 and under [SOURce:]DIGital:DATA and [SOURce:]DIGital:FUNCtion commands in chapter 8. The electrical characteristics of the digital connector are described in appendix A.

Table 3-3. FLT/INH DIGital I/O Connector

PIN FAULT/INHIBIT DIGITAL I/O

1 FLT Output Output 0 2 FLT Common Output 1 3 INH Input Input/Output 2 4 INH Common Common

3 - Installation

Coil Current

0.25A Max.

NOTE: Connectors

are removable

INH FLT

4 3 2 1

. . . .

+ - +

A) Relay Circuits

Figure 3-7. Digital I/O Examples

Controller Connections

+16.5V Max.

Relay Driver

Ports 0, 1, 2

(contains internal

clamp diodes for inductive flyback)

Digital Output

Ports 0, 1, 2

TTL, AS, CMOS, HC

Digital Input

Port 2

B) Digital Interface Circuits

The dc source can be controlled either through an HP-IB or an RS-232 interface.

HP-IB Interface

Each dc source has its own HP-IB bus address, which can be set using the front panel Address key as described in chapter 5. HP-IB address data is stored in non-volatile memory. The dc source is shipped with its HP-IB address set to 5.

Dc sources may be connected to the HP-IB interface in series configuration, star configuration, or a combination of the two, provided the following rules are observed:

♦ The total number of devices including the controller is no more than 15.

♦ The total length of all cables used is no more than 2 meters times the number of devices connected

together, up to a maximum of 20 meters. (Refer to table 2-2 for a list of HP-IB cables available from Hewlett-Packard.)

♦ Do not stack more than three connector blocks together on any HP-IB connector.

♦ Make sure all connectors are fully seated and the lock screws are firmly finger-tightened.

RS-232 Interface

The dc source has an RS-232 programming interface, which is activated by commands located in the front panel programming. When the RS-232 interface is selected, the HP-IB interface is disabled.

Address menu. All SCPI and COMPatibility commands are available through RS-232

Installation - 3

The RS-232 connector is a DB-9, male connector. Adapters are available to connect the dc source to any computer or terminal with a properly configured DB-25 connector (see Table 2-2).

1 2 3 4 5

6 7 8 9

Figure 3-6. RS-232 Connector

Pin Input/Output Description

1 - no connection

2 Input Receive Data (RxD)

3 Output Transmit Data (TxD)

4 Output Data Terminal Ready (DTR)

5 Common Signal ground

6 Input Data Set Ready (DSR)

7 Output Request to Send (RQS)

8 Input Clear to Send (CTS)

9 - no connection

Turn-On Checkout

Checkout Procedure

Successful tests in this chapter provide a high degree of confidence that the unit is operating properly. For verification tests, see appendix B. Complete performance tests are given in the Service Guide.

NOTE: To perform the checkout procedure, you will need a wire for shorting the output

terminals together.

The following procedure assumes that the unit turns on in the factory-default state. If you need more information about the factory default state, refer to the *RST command in chapter 8. Note that the values shown in the Display column may not exactly match the values that appear on the front panel of your unit.

If you have not already done so, connect the power cord to the unit and plug it in.

Procedure Display Explanation

1. Turn the unit on. The dc

source undergoes a selftest when you first turn it on.

**********

ADDRESS 5

0.004V .0006A

During selftest, all display segments are briefly lit, followed by the HP-IB Address.

The display then goes into meter mode with the Dis annunciator on, and all others off. In Meter mode the

*****V digits indicate the output voltage and the *****A digits indicate the output current. The flashing

digit on the display indicates the digit that will be affected if changes are made to the displayed values using the rotary control or the Å and Æ keys. You will only see the changes if the output is ON.

NOTE: Press the Meter key to exit a menu at any time and return to meter mode. If the Err

annunciator on the display is on, press the Shift key followed by the Error key to see the error number. See table 4-1 at the end of this chapter.

2. Check that the dc source

fan is on

Press Voltage,

Enter Number, <15>, Enter

You should be able to hear the fan and feel the air

coming from the back of the unit.

VOLT 0.000

VOLT 15

Programs the output to 15 volts. After the value is entered, the display returns to Meter mode. Because the output has not been enabled, the meter still indicates approximately 0 volts.

Press Output On/Off

Press Shift, OV

15.003V 0.0006A

VOLT:PROT 22.00 Display shows the overvoltage protection trip voltage

Turns the output on. The Dis annunciator should be off and CV should be on.

for your unit.

4 - Turn-On Checkout

Procedure Display Explanation

Press Enter Number, 8, Enter

Press Shift, OV,

Enter Number, <22>, Enter

Press Shift, Prot Clear

Press Output on/off

10. Connect a jumper wire

across the + and - output terminals.

11.

Press Output on/off.

VOLT:PROT 8

0.449V 0.145A

VOLT:PROT <22> Programs the OVP to a value greater than the output

<15.003>V

0.0034A

Turn the output off.

Shorts the output of the unit.

0.0005V

<0.3071>A

Programs the OVP to 8 volts, which is less than the previously set output voltage.

Because the OVP voltage entered was less than the output voltage, the OVP circuit tripped. The output dropped to zero, CV turned off, and Prot turned on.

voltage setting of the unit. This prevents the OV circuit from tripping again when the protection condition is cleared.

Clears the protection condition, thus restoring the output of the unit. Prot turns off and CV turns on.

The CC annunciator is on, indicating that the unit is in constant current mode. The unit is sourcing output current at 10% of the maximum rating (the default output current limit setting).

12.

Press Current,

Enter Number, <3>, Enter.

13.

Press Shift, OCP

14.

Press Shift, OCP

15.

Press Shift, Prot Clear

16. Turn the unit off and

remove the shorting wire from the output terminals.

0.0452V

<2.998>A

0.0005V 0.0003A You enabled the overcurrent protection circuit. The

0.0005V 0.0003A You have disabled the overcurrent protection circuit.

0.0452V

<2.998>A

The next time the unit turns on it will be restored to the

Programs the output current to 3 amperes.

circuit then tripped because the unit was operating in constant current mode. The CC annunciator turns off and the OCP and Prot annunciators come on.

The OCP annunciator turns off.

Restores the output. The Prot annunciator turns off. CC is on.

*RST or factory default state.

Turn-On Checkout - 4

In Case of Trouble

Error Messages

Dc source failure may occur during power-on selftest or during operation. In either case, the display may show an error message that indicates the reason for the failure.

Selftest Errors

Pressing the

Shift, Error keys will show the error number. Selftest error messages appear as: ERROR

<n> where "n" is a number listed in the following table. If this occurs, turn the power off and then back on to see if the error persists. If the error message persists, the dc source requires service.

Table 4-1. Power-On Selftest Errors

Error No. Failed Test

Error 0 No error

Error 1 Non-volatile RAM RD0 section checksum failed

Error 2 Non-volatile RAM CONFIG section checksum failed

Error 3 Non-volatile RAM CAL section checksum failed

Error 4 Non-volatile RAM STATE section checksum failed

Error 5 Non-volatile RST section checksum failed

Error 10 RAM selftest

Error 11 to 14 VDAC/IDAC selftest 1 to 4

Error 15 OVDAC selftest

Error 80 Digital I/O selftest error

Runtime Error Messages

Appendix C lists other error messages that may appear at runtime. If the front panel display shows OVLD , this indicates that the output voltage or current is beyond the range of the meter readback circuit. If this is the case, check that the setting of the output compensation is correct for the phone you are testing. If the front panel display indicates -- -- -- -- -- , an HP-IB measurement is in progress.

Line Fuse

If the dc source appears "dead" with a blank display and the fan not running, check your power source to be certain line voltage is being supplied to the dc source. If the power source is normal, the fuse may be defective.

1. Turn off the front panel power switch and unplug the power cord.

2. Remove the fuse from the rear panel.

3. If the fuse is defective, replace it with a fuse of the same type (see Input Connections in chapter 3).

4. Turn on the dc source and check the operation.

NOTE: If the dc source has a defective fuse, replace it only once. If it fails again, the dc source

requires service.

Front panel Operation

Introduction

Here is what you will find in this chapter:

♦ a complete description of the front panel controls ♦ front panel programming examples

NOTE: The dc source must be in set to Local mode to use the front panel controls. Press the

Local key on the front panel to put the unit in local mode.

Front Panel Description

LINE

CV CC

SYSTEM FUNCTION

Local

Off

66311A 0-15V/0-3A Mobile Communications DC Source

Unr Dis OCP

Error

Address

Recall

Input

Meter

Protect

Cal Shift Rmt Addr Err SRQ

Prot

890

Voltage

Current

Output

CalOCPProt CirSave

Output

On/Off

Enter

Number

Enter

ENTRY

OUTPUT

50 VDC

Max

Figure 5-1. Front Panel, Overall View

1111 Display

14-character vacuum fluorescent display for showing output measurements and programmed values.

5 – Front Panel Operation

2222 Annunciators

3333 Rotary Control

4444 Output

Connectors

5555 Line

6666 System Keys

Annunciators light to indicate operating modes and status conditions:

CV The dc source output is in constant-voltage mode. CC The dc source output is in constant-current mode. Unr The dc source output is in an unregulated state. Dis The dc source output is disabled (off). OCP The overcurrent protection state is enabled. Prot One of the dc source's output protection features is activated. Cal The dc source is in calibration mode. Shift The Shift key is pressed to access an alternate key function. Rmt The selected interface (HP-IB or RS-232) is in a remote state. Addr The interface is addressed to talk or to listen. Err There is a message in the SCPI error queue. SRQ The interface is requesting service from the controller.

The rotary control lets you set the output voltage or current as well as menu parameters. Press the knob.

Front panel binding posts let you connect loads to the front of the unit. Before using the front panel binding posts, make sure that the sense switch on the back of the unit is set to Local. Specifications are not guaranted at the front panel.

This turns the dc source on or off.

The system keys let you: Return to Local mode (front panel control) Set the dc source HP-IB address Selects the remote programming interface Set the RS-232 interface communication baud rate and parity bit Display SCPI error codes and clear the error queue Save and recall up to 4 instrument operating configurations Select the programming language Enable/disable the remote front panel interface

ÃÃÃÃ and ÄÄÄÄ to select the resolution, then adjust the value with

7777 Function Keys

8888 Entry Keys

Function access command menus that let you: Enable or disable the output Select metering functions Program output voltage and current Display the protection status state Set and clear protection functions Set the output state at power-on Calibrate the dc source Select the output compensation

S and T scroll through the front panel menu commands

Entry keys let you: Enter programming values Increment or decrement programming values

Å and Æ select the front panel menu parameters

Front Panel Operation - 5

System Keys

Refer to the examples later in this chapter for more details on the use of these keys.

SYSTEM

Error

Local

Figure 5-2. System Keys

This is the blue, unlabeled key, which is also shown as in this guide.

Pressing this key accesses the alternate or shifted function of a key (such as

ERROR ). Release the key after you press it. The Shift annunciator is lit,

indicating that the shifted keys are active.

Local

Press to change the dc source's selected interface from remote operation to local (front panel) operation. Pressing the key will have no effect if the interface state is already Local, Local-with-Lockout, or Remote-with-Lockout.

Address

Press to access the system address menu. This menu lets you configure the dc

source's interface. All Address menu entries are stored in non-volatile memory.

Display Command Function

value = a numeric value char = a character string parameter Use and to scroll through the command list. Use and to scroll through the parameter list.

Recall

ADDRESS <value> Sets the HP-IB Address

INTF <char> Selects an interface (HPIB or RS232)

BAUDRATE<char> Selects baud rate (300, 600, 1200, 2400, 4800, 9600)

PARITY <char> Message parity (NONE, EVEN, ODD, MARK, SPACE)

FLOW <char> Flow control (XON-XOFF, RTS-CTS, DTR-DSR, NONE)

LANG <char> Selects language (SCPI or COMP)

REMOTE FP <char> Enable/disable HP14575A front panel interface (ON or OFF)

T S

Å Æ

Press to place the dc source into a previously stored state. You can recall up to 4 previously stored states (0 through 3).

Shift

Press to display the system error codes stored in the SCPI error queue. This

Error

action also clears the queue. If there is no error in the queue, 0 is displayed.

Save Shift

Press to store an existing dc source state in non-volatile memory. The parameters saved are listed under *SAV as described in chapter 8. You can save up to 4 states (0 through 3).

Address

Save

Recall

Shift

5 – Front Panel Operation

Function Keys

Refer to the examples later in this chapter for more details on the use of these keys.

FUNCTION

Input

Meter

Prot Cir

Protect

Voltage

OCP

Current

Output

Cal

Output

On/Off

Figure 5-3. Function Keys

Immediate Action Keys

Immediate action keys immediately execute their corresponding function when pressed. Other function keys have commands underneath them that are accessed when the key is pressed.

Output On/Off

Shift

Prot Clr

OCP

This key toggles the output of the dc source between the on and off states. It immediately executes its function as soon as you press it. When off, the dc source output is disabled and the Dis annunciator is on.

Press this key to reset the protection circuit and allow the unit to return to its last programmed state. The condition that caused the protection circuit to become active must be removed prior to pressing this key, or the unit will shut down again and display the Prot annunciator again.

Press this key to toggle between OCP enabled and disabled. If OCP is enabled the output will become disabled if the output mode changes from CV to CC mode. The OCP annunciator indicates the state of OCP.

Scrolling Keys

Scrolling keys let you move through the commands in the presently selected function menu.

cccc dddd

Press to bring up the next command in the list. Press to go back to the previous command in the list. Function menus are circular; you can return to the starting position by continuously pressing either key. The following example shows the commands in the Input function menu:

CURR:RANGE <char>

CURR:DET <char>

Front Panel Operation - 5

Metering Keys

Metering keys control the metering functions of the dc source. As set from the factory, all front panel measurements are calculated from a total of 2048 readings taken at a 46.8 microsecond sampling rate. Therefore, the factory default acquisition time for a single front panel measurement is about 100 milliseconds. Refer to “Making Front Panel Measurements” for more information about changing the front panel sampling rate and the number of measurement points.

NOTE: The front panel sample rate and data point settings are separate and independent of the

sample rate and data point settings that are programmed over the HP-IB interface. When an HP-IB measurement is in progress, the front panel display temporarily indicates

-- -- -- -- --. Front panel measurements resume when the HP-IB measurement completes. HP-IB measurements are discussed in chapter 7.

Meter

Press this key to access the meter menu list. Also use this key to exit a menu at

any time and return to meter mode.

Display Measurement

Shift Input

Display Command Function

<reading>V <reading>A Measures output dc voltage and current

<reading>V MAX Measures peak output voltage

<reading>V MIN Measures minimum output voltage

<reading>V HIGH Measures the high level of a voltage pulse waveform

<reading>V LOW Measures the low level of a voltage pulse waveform

<reading>V RMS Measures rms voltage

<reading>A MAX Measures peak output current

<reading>A MIN Measures minimum output current

<reading>A HIGH Measures the high level of a current pulse waveform

<reading>A LOW Measures the low level of a current pulse waveform

<reading>A RMS Measures rms current

Press this key to access the following metering functions.

CURR:RANGE <char> Select current range (AUTO, LOW or HIGH)

CURR:DET <char> Select current measurement bandwidth (ACDC or DC)

TINT <value> Sets the front panel measurement interval in seconds

(15.6 µs to 1 second)

POINTS <char> Sets the number of points in the front panel measurement

buffer ( 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, 2048)

reading = the returned measurement value = a numeric value char = a character string parameter Use and to scroll through the menu commands. Use and to scroll through the menu parameters.

Notes:

T S Å Æ Ã Ä

Use and to select a digit in a numeric entry field.

5 – Front Panel Operation

Output Control Keys

Output control keys control the output functions of the dc source.

Voltage

Press this key to access the voltage menu.

Display Command Function

Current

VOLT <value> Sets the output voltage

Press this key to access the current menu.

Display Command Function

Output

CURR <value> Sets the output current

Press this key to access the output menu list.

Display Command Function

Protect

*RST Places the dc source in the factory-default state

PON:STATE <char> Select the power-on state command (RST or RCL0)1

RI <char> Sets the remote inhibit mode (LATCHING, LIVE, or OFF)1

DFI <char> Sets the discrete fault indicator state (ON or OFF)

DFI:SOUR <char> Selects the DFI source (QUES, OPER, ESB, RQS, or OFF)2

PORT <char> Sets the output port functions (RIDFI or DIGIO)1

DIGIO <char> Sets and reads the I/O port value (0 through 7)

PROT:DLY <value> Sets the output protection delay in seconds

TYPE:CAP <char> Sets the output compensation (HIGH or LOW) 1

Press this key to display protection status.

Display Command Function

OV Shift

OC OT OV RI -- Status of the protection features (example shows all tripped)

-- -- -- -- -- Status of the protection features (example shows none tripped)

Press this key to access the overvoltage protection menu.

Display Command Function

Cal Shift

PROT:STAT <char> Enables or disables overvoltage protection (ON or OFF)

PROT:LEV <value> Sets the overvoltage protection level

This key accesses the calibration menu (Refer to Appendix B for details).

value = a numeric value char = a character string parameter Use and to scroll through the menu commands. Use and to scroll through the menu parameters.

Notes:

These parameters are stored in non-volatile memory

These status summary bits are explained in chapter 7

T S Å Æ Ã Ä

Use and to select a digit in a numeric entry field.

Front Panel Operation - 5

Entry Keys

Refer to the examples later in this chapter for more details on the use of these keys.

Cir Entry

Enter

Number

Enter

ENTRY

Backspace

Figure 5-4. Entry Keys

ÆÆÆÆ ÅÅÅÅ

These keys let you scroll through choices in a parameter list that apply to a specific command. Parameter lists are circular; you can return to the starting position by continuously pressing either key. If the command has a numeric range, these keys increment or decrement the existing value. In meter mode, these keys can be used to adjust the magnitude of the output voltage or current. Only the flashing digit is changed by these keys. Use the

ÃÃÃÃ and ÄÄÄÄ keys to move

the flashing digit.

These keys move the flashing digit in a numeric entry field to the right or left.

ÄÄÄÄ ÃÃÃÃ

This lets you increment or decrement a specific digit in the entry field using the

ÅÅÅÅ and ÆÆÆÆ keys or the RPG knob.

Enter Number

Used only to access a third level key function - the numeric entry keys. These

third level function keys are labeled in green.

Back space

The backspace key deletes the last digit entered from the keypad. This key lets

9 0

−−−−

0 through 9 are used for entering numeric values. . is the decimal point. −

the minus sign. For example, to enter 33.6 press:

Enter

Enter Number, 3, 3, . , 6,

− is

−−

you correct one or more wrong digits before they are entered.

Shift

This key aborts a keypad entry by clearing the value. This key is convenient for

Clear Entry

correcting a wrong value or aborting a value entry. The display then returns to the previously set function.

Enter

This key executes the entered value or parameter of the presently accessed

command. Until you press this key, the parameters you enter with the other Entry keys are displayed but not entered into the dc source. Before pressing

Enter, you can change or abort anything previously entered into the display.

After

Enter is pressed, the dc source returns to Meter mode.

5 – Front Panel Operation

Examples of Front Panel Programming

You will find these examples on the following pages: 1 Setting the output voltage, current, and compensation 2 Querying and clearing output protection 3 Making front panel measurements 4 Programming the digital port 5 Setting the HP-IB address or RS-232 parameters 6 Saving and recalling operating states

1 - Setting the Output Voltage, Current, and Compensation

This example shows you how to set the output voltage and current. It also shows you how to set the compensation circuit for either high or low capacitance cellular phones. Note that no front panel changes affect the output of the unit unless it has been enabled.

Set the output voltage

Action Display

1. To enter an approximate value without using the voltage menu: On the Entry keypad,

press Ã or Ä to select the 1's digit in the voltage field. Then rotate the front panel RPG knob to obtain 7 V.

If the unit is in CC mode, you won't see the output voltage change until the voltage setting is low enough to cause the unit to go into CV mode.

The easiest way to enter an accurate value: On the Function keypad, press Voltage. On the Entry keypad, press Enter Number, 7, Enter.

3. To make minor changes to an existing value: On the Function keypad, press

Voltage. On the Entry keypad, press Ã or Ä to select the digit in the numeric field that you wish to change. For example, move the flashing digit to the ones column to change a value in this column. Then, press Å to scroll from 7.000 to 8.000. Then press Enter.

7.003V 0.004A

VOLT 7.000

VOLT 8.000

Set the output current limit

Action Display

1. To enter an approximate value without using the current menu: On the Entry keypad,

press Ã or Ä to select the tenths digit in the current field. Rotate the front panel RPG knob to obtain 0.4A.

If the unit is in CV mode, you will not see the output current change until the current setting is low enough to cause the unit to go into CC mode.

The easiest way to enter an accurate value: On the Function keypad, press Current. On the Entry keypad, press Enter Number, .4, Enter.

3. To make minor changes to an existing value: On the Function keypad, press

Current. On the Entry keypad, press Ã or Ä to select the digit in the numeric field that you wish to change. For example, move the flashing digit to the tenths column to change a value in this column. Then, press Å to scroll from 0.400 to 0.500. Then press Enter.

8.003V 0.400A

CURR 0.400

CURR 0.500

NOTE: To output currents pulses greater than 3 A and up to 5 A peak, you must set the output

current limit to greater than 3 amperes (3.0712 amperes max).

Front Panel Operation - 5

Set the output compensation

Action Display

On the Function keypad, press Output. Then press T until you obtain the TYPE:CAP command. Use the Æ key and select either LOW or HIGH. Then press Enter. Use 5 µF. Use LOW compensation for phones with input capacitances under 5 µF.

HIGH compensation for phones with input capacitances greater than

TYPE:CAP HIGH

Enable the output

Action Display

On the Function keypad, press Output On/Off to enable the output. The Dis annunciator will go off, indicating that the voltage is now applied to the output terminals. The A display indicates the actual output current.

8.003V 0.500A

2 - Querying and Clearing Output Protection and Errors

If an overvoltage, overcurrent, overtemperature or remote inhibit condition occurs, the Prot annunciator

on the front panel will be on and the dc source will disable its output. If necessary, you can disable the overcurrent or overvoltage protection circuit if its operation interferes with the proper operation of your phone test. Note that if you disable the overvoltage protection, the equipment under test will not be protected from output voltage overshoot conditions.

Error messages can occur at any time during the operation of the unit. When the Err annunciator on the front panel is on it means that either an error has occurred on the HP-IB bus, or a selftest error has occurred. Appendix C lists error numbers and descriptions.

Query and clear the dc source overcurrent protection as follows:

Action Display

On the Function keypad, press Protect. In this example, OC indicates that an overcurrent condition has occurred. Other protection indicators are: OT (overtemperature), OV (overvoltage), and RI (remote inhibit).

On the Function keypad, press Current. This displays the present current limit. CURR 3.0712

3. To restore normal operation after the cause of the overcurrent condition has been

removed, press Shift, Prot Clr. The Prot annunciator then will go off.

To disable overcurrent protection, press Shift, OCP. This key toggles between OCP enabled and disabled. The OCP annunciator is off when OCP is disabled.

OC -- -- -- --

Disable Overvoltage Protection as follows:

On the Function keypad, press press Shift, OV. Then press T to obtain the PROT:STAT command. Use the Æ key and select OFF to disable the overvoltage protection function. Then press Enter. To recall this state when the unit is powered on, save this instrument setup or state in location 0 as explained in example #6.

PROT:STAT OFF

Query and Clear Errors as follows:

On the Function keypad, press press Shift, Error. This displays and clears the error in the error queue. Repeatedly press these keys to clear all errors in the queue. If errors persist, your unit may require service.

ERROR 0

5 – Front Panel Operation

3 – Making Front Panel Measurements

As shipped from the factory, front panel measurements are calculated from a total of 2048 readings taken at a 46.8 microsecond sampling rate. The unit alternates between voltage and current measurements. Therefore, the data acquisition time for a single front panel voltage or current measurement is about 100 milliseconds. This sampling rate and data acquisition time combined with a built-in windowing function, reduces errors due to sampling a non-integral number of cycles of a waveform for frequencies of 25 Hz or greater. Note that the windowing function is less accurate when measuring output waveforms for frequencies less than 25 Hz, causing the front panel meter to jitter.

The following figure illustrates the various measurements that are returned from a sampled output waveform. These include measurements such as peak (max), minimum, high level, and low level as illustrated in the following figure. Rms and dc voltages are calculated from the number of points in the measurement window.

V or A MAX

V or A HIGH

V or A LOW

V or A MIN

100 millisecond acquisition time

46.8 microsecond sampling rate

NOTE:

Measurement samples may not

coincide with the actual maximum

or minimum point of the waveform.

Figure 5-5. Default Front Panel Measurement Parameters

There are no trigger controls for front panel measurements. However, you can vary both the sampling rate and the number of data points in each front panel measurement using commands in the Input menu. With this flexibility, measurement accuracy can be improved for waveforms with frequencies as low as several Hertz. The sample buffer size may be varied from 1 to 2048 data points in discrete binary values. The sampling rate may be varied from 15.6 microseconds to 1 second. Values are rounded to the nearest

15.6 microsecond interval. Note that the front panel sample interval and buffer size settings are independent of the sample interval and buffer size that you program over the HP-IB. This is because you can qualify measurement triggers over the HP-IB, which makes the HP-IB measurements independent of the front panel measurements. Refer to chapter 8 for more information about HP-IB measurements.

Two current measurement ranges can be selected in the Input menu. A high current range is available for measuring output currents of up to 7 amperes. A low current range is available for improved resolution when measuring output currents below 20 milliamperes. The low current measurement range is accurate to 0.1% of the reading ±2.5 microamperes. When the current Range is set to AUTO, the unit automatically selects the range with the best measurement resolution.

NOTE: If the front panel display indicates OVLD, the output has exceeded the measurement

capability of the instrument. If the front panel display indicates -- -- -- -- -- -- , an HP-IB measurement is in progress.

Front Panel Operation - 5

Use the Meter menu for making front panel measurements:

Action Display

For current measurements, press Shift, Input. Then press Æ until you obtain the CURR:RANG AUTO command. Press Enter to activate autoranging. Two other selections are also available. Select the HIGH range when measuring currents above 20 mA. Select the LOW range for improved resolution when measuring currents below 20 mA. Note that the LOW range is only appropriate for making dc measurements.

For output waveform measurements, press Shift, Input. Then press T until you obtain the CURR:DET command. Check to make sure that the ACDC current detector is selected. This provides the best accuracy for waveform measurements. Only select the DC current detector if you are making dc current measurements and you require a dc measurement offset better than 1mA on the High current measurement range. Press Enter to activate any changes.

CURR:RANG AUTO

CURR:DET ACDC

NOTE: In the LOW current measurement range, the current detector is fixed at DC. With the

current detector in dc, accurate current measurements cannot be made on waveforms with frequency contents over 1 kilohertz.

3. To change the front panel time interval and buffer size for output waveform

measurements, press Shift, Input. Then press T until you obtain the TINT command. Use the Entry keys to enter a value from 15.6 microseconds to 1 second in seconds. Then press Enter.

Continue by pressing Shift, Input and T until you obtain the POINT command. Press Æ to select a different buffer size. The choices are: 1, 2, 4, 8, 16, 32, 64, 128, 256, 512, 1024, and 2048. Then press Enter.

TINT 0.002

POINT 1024

One reason to change the front panel time interval and data points is if the waveform being measured has a period shorter than 3 times the present front panel acquisition time.

On the Function keypad press Meter and press T repeatedly to access the following measurement parameters:

♦ dc voltage and current ♦ peak voltage ♦ minimum voltage ♦ high level of a voltage pulse waveform ♦ low level of a voltage pulse waveform ♦ rms voltage ♦ peak current ♦ minimum current ♦ high level of a current pulse waveform ♦ low level of a current pulse waveform ♦ rms current

<reading>V <reading>A <reading>V MAX <reading>V MIN <reading>V HIGH <reading>V LOW <reading>V RMS <reading>A MAX <reading>A MIN <reading>A HIGH <reading>A LOW <reading>A RMS

5 – Front Panel Operation

4 - Programming External Protection and the Digital Port Functions

Your dc source is shipped with the output port function set to RIDFI mode. In this mode the port functions as a remote inhibit input with a discrete fault indicator output signal. You can also configure the port to act as a Digital Input/Output device.

To configure the RIDFI mode of the port, proceed as follows:

Action Display

On the Function keypad, press Output.

2. Scroll through the Output menu by pressing T. The PORT command lets you select

either the RIDFI or the DIGIO function. Press Enter when done.

3. Scroll to the RI command to configure the Remote INHibit indicator. Use the Å and Æ keys to select either LIVE or LATCHING, either of which enable the RI indicator. Then press Enter. With RI enabled, a low-true on the INH input will disable the output of the unit. LIVE causes the output of the unit to track the state of the INH input. LATCHING latches the output of the unit off in response to the inhibit signal.

4. Access the Output menu again and scroll through the menu. The DFI command lets you enable the Discrete Fault Indicator. Use the Æ key and select ON to enable the FLT output. Then press Enter. With the FLT output enabled, the open-collector logic signal can be used to signal external devices when a fault condition is detected.

5. Scroll to the DFI:SOUR command to select the internal source that drives this signal. Use the Æ key to select from the RQS or ESB bits, or the Operation or Questionable status registers. Then press Enter. Status summary bits are explained in chapter 7.

*RST

PORT RIDFI

RI LIVE RI LATCHING

DFI ON

DFI:SOUR RQS DFI:SOUR ESB DFI:SOUR OPER DFI:SOUR QUES

To configure the DIGIO mode of the port, proceed as follows:

Action Display

On the Function keypad, press Output.

*RST

2. Scroll through the Output menu by pressing T. The PORT command lets you select either the RIDFI or the DIGIO function. Press Enter when done.

3. Scroll to the DIGIO command to set and read the Digital Input/Output Port. Press Enter Number and enter a number from 0 to 7 to program the three bits (0 programs all bits low; 7 programs all bits high). Press Enter when done.

PORT DIGIO

DIGIO 5

5 - Setting the HP-IB Address and RS-232 Parameters

Your dc source is shipped with the HP-IB address set to 5. This address can only be changed from the front panel using the Address menu located under the RS-232 interface and specify RS-232 parameters such baud rate and parity.

Set the HP-IB address as follows:

Action Display

On the System keypad, press Address.

Enter the new address. For example, Press Enter Number, 7, Enter.

Address key. This menu is also used to select the

ADDRESS 5

ADDRESS 7

Front Panel Operation - 5

Configure the RS-232 interface as follows:

Action Display

On the System keypad, press Address.

2. Scroll through the Address menu by pressing T. The interface command lets you

select the RS-232 interface. The baudrate command lets you select the baudrate. The parity command lets you select the parity. The flow command selects the flow control options.

The Å and Æ keys let you select the command parameters. Press Enter when done.

ADDRESS 5

INTF RS232 BAUDRATE 9600 PARITY EVEN FLOW XON-XOFF

6 - Saving and Recalling Operating States

You can save up to 4 states (from location 0 to location 3) in non-volatile memory and recall them from the front panel. All programmable settings are saved. This capability is only available when the unit is set to the SCPI programming language.

NOTE: You can program the unit to automatically power-on according to the operating state that

is saved in location 0 as shown in the third example on this page.

Save an operating state in location 0 as follows:

Action Display

1. Set the instrument to the operating state that you want to save.

Save this state to location 0. Press Save, Enter Number, 0, Enter.

*SAV 0

Recall a saved state as follows:

Action Display

Recall the state saved in location 0 by pressing Recall, Enter Number, 0, Enter

*RCL 0

Select the power-on state of the dc source as follows:

Action Display

On the Function keypad, press Output, and scroll through the Output menu until you get to the PON state command.

2. Use the Å and Æ keys to select either RST or RCL0. RST sets the power-on state of

the unit as defined by the *RST command. RCL0 sets the power-on state of the unit to the state saved in *RCL location 0. Press Enter when done.

PON:STATE RST

Clear the non-volatile memory of the dc source as follows:

Action Display

On the Function keypad, press Output, Enter. This returns the unit to the factorydefault settings.

Save these settings to location 0. Press Save, Enter Number, 0, Enter.

3. Repeat step #2 for memory locations 1 through 3. *SAV 1

*RST

*SAV 0

*SAV 2 *SAV 3

Introduction to Programming

HP-IB Capabilities of the DC Source

All dc source functions except for setting the HP-IB address are programmable over the HP-IB. The IEEE 488.2 capabilities of the dc source are listed in the Specifications Table in Appendix A.

HP-IB Address

The dc source operates from an HP-IB address that is set from the front panel. To set the HP-IB address, press the Address key on the front panel and enter the address using the Entry keys. The address can be set from 0 to 30. The HP-IB address is stored in non-volatile memory.

ADDRESS <value> Enter a value to set the HP-IB Address

RS-232 Capabilities of the DC Source

The dc source provides an RS-232 programming interface, which is activated by commands located under the front panel Address key. All SCPI and COMPatibility commands are available through RS-232 programming. When the RS-232 interface is selected, both the HP-IB interface and the optional HP 14575A Remote Front Panel interface is disabled.

The EIA RS-232 Standard defines the interconnections between Data Terminal Equipment (DTE) and Data Communications Equipment (DCE). The dc source is designed to be a DTE. It can be connected to another DTE such as a PC COM port through a null modem cable.

NOTE: The RS-232 settings in your program must match the settings specified in the front panel

Address menu. Press the front panel Address key if you need to change the settings.

RS-232 Data Format

The RS-232 data is a 10-bit word with one start bit and one stop bit. The number of start and stop bits is not programmable. The following parity options are selectable using the front panel Address key:

EVEN Seven data bits with even parity ODD Seven data bits with odd parity MARK Seven data bits with mark parity (parity is always true) SPACE Seven data bits with space parity (parity is always false) NONE Eight data bits without parity

Parity options are stored in non-volatile memory.

Baud Rate

The front panel Address key lets you select one of the following baud rates, which is stored in nonvolatile memory: 300 600 1200 2400 4800 9600

6 - Introduction to Programming

RS-232 Flow Control

The RS-232 interface supports several flow control options that are selected using the front panel Address key. For each case, the dc source will send a maximum of five characters after holdoff is asserted by the controller. The dc source is capable of receiving as many as fifteen additional characters after it asserts holdoff.

XON-XOFF A software handshake that uses the ASCII control code DC3 (decimal code

19) to assert hold-off, and control code DC1 (decimal code 17) to release hold-off.

RTS-CTS The dc source asserts its Request to Send (RTS) line to signal hold-off

when its input buffer is almost full, and it interprets its Clear to Send (CTS) line as a hold-off signal from the controller.

DTR-DSR The dc source asserts its Data Terminal Ready (DTR) line to signal hold-

off when its input buffer is almost full, and it interprets its Data Set Ready (DSR) line as a hold-off signal from the controller.

NONE There is no flow control.

Flow control options are stored in non-volatile memory.

Introduction to SCPI

SCPI (Standard Commands for Programmable Instruments) is a programming language for controlling instrument functions over the HP-IB. SCPI is layered on top of the hardware-portion of IEEE 488.2. The same SCPI commands and parameters control the same functions in different classes of instruments. For example, you would use the same DISPlay command to control the dc source display and the display of a SCPI-compatible multimeter.

SCPI References

The following documents will assist you with programming in SCPI:

♦ Standard Commands for Programmable Instruments Volume 1, Syntax and Style

♦ Standard Commands for Programmable Instruments Volume 2, Command References

♦ Standard Commands for Programmable Instruments Volume 3, Data Interchange Format

♦ Standard Commands for Programmable Instruments Volume 4, Instrument Classes

To obtain a copy of the above documents, contact: Fred Bode, Executive Director, SCPI Consortium, 8380 Hercules Drive, Suite P3, Ls Mesa, CA 91942, USA

HP-IB References

The most important HP-IB documents are your controller programming manuals - HP BASIC, HP-IB Command Library for MS DOS, etc. Refer to these for all non-SCPI commands (for example: Local Lockout).

Introduction to Programming - 6

The following are two formal documents concerning the HP-IB interface:

♦ ANSI/IEEE Std. 488.1-1987 IEEE Standard Digital Interface for Programmable Instrumentation.

Defines the technical details of the HP-IB interface. While much of the information is beyond the need of most programmers, it can serve to clarify terms used in this guide and in related documents.

♦ ANSI/IEEE Std. 488.2-1987 IEEE Standard Codes, Formats, Protocols, and Common Commands.

Recommended as a reference only if you intend to do fairly sophisticated programming. Helpful for finding precise definitions of certain types of SCPI message formats, data types, or common commands.

The above two documents are available from the IEEE (Institute of Electrical and Electronics Engineers), 345 East 47th Street, New York, NY 10017, USA. The WEB address is www.ieee.org.

Conventions Used in This Guide

Angle brackets < > Items within angle brackets are parameter abbreviations. For example,

<NR1> indicates a specific form of numerical data.

Vertical bar | Vertical bars separate alternative parameters. For example, NORM |

TEXT indicates that either "TEXT" or "NORM" can be used as a parameter.

Square Brackets [ ] Items within square brackets are optional. The representation [SOURce:].

VOLTage means that SOURce: may be omitted.

Braces { } Braces indicate parameters that may be repeated zero or more times. It is

used especially for showing arrays. The notation <A>{<,B>} shows that parameter "A" must be entered, while parameter "B" may be omitted or may be entered one or more times.

Boldface font

Computer font Computer font is used to show program lines in text.

Boldface font is used to emphasize syntax in command definitions. TRIGger:COUNt:CURRent <NRf> shows command definition.

TRIGger:COUNt:CURRent 10 shows a program line.

Types of SCPI Commands

SCPI has two types of commands, common and subsystem.

♦ Common commands generally are not related to specific operation but to controlling overall dc

source functions, such as reset, status, and synchronization. All common commands consist of a three-letter mnemonic preceded by an asterisk: *RST *IDN? *SRE 8

♦ Subsystem commands perform specific dc source functions. They are organized into an inverted tree

structure with the "root" at the top. The following figure shows a portion of a subsystem command tree, from which you access the commands located along the various paths. You can see the complete tree in Table 8-1.

6 - Introduction to Programming

[

]

[

]

[

]

ROOT

:OUTPut

:STATus

:STATe

:DFI

:PON

:PROTection

:OPERation

:STATe

:SOURce

:STATe

:CLEar

:DELa

:EVEN

:CONDition?

Figure 6-1. Partial Command Tree

Multiple Commands in a Message

Multiple SCPI commands can be combined and sent as a single message with one message terminator. There are two important considerations when sending several commands within a single message:

♦ Use a semicolon to separate commands within a message.

♦ There is an implied header path that affects how commands are interpreted by the dc source.

The header path can be thought of as a string that gets inserted before each command within a message. For the first command in a message, the header path is a null string. For each subsequent command the header path is defined as the characters that make up the headers of the previous command in the message up to and including the last colon separator. An example of a message with two commands is:

OUTP:STAT ON;PROT:DEL 2

which shows the use of the semicolon separating the two commands, and also illustrates the header path concept. Note that with the second command, the leading header "OUTP" was omitted because after the "OUTP:STAT ON" command, the header path was became defined as "OUTP" and thus the instrument interpreted the second command as:

OUTP:PROT:DEL 2

In fact, it would have been syntactically incorrect to include the "OUTP" explicitly in the second command, since the result after combining it with the header path would be:

OUTP:OUTP:PROT:DEL 2

which is incorrect.

Moving Among Subsystems

In order to combine commands from different subsystems, you need to be able to reset the header path to a null string within a message. You do this by beginning the command with a colon (:), which discards any previous header path. For example, you could clear the output protection and check the status of the Operation Condition register in one message by using a root specifier as follows:

OUTPut:PROTection:CLEAr;:STATus:OPERation:CONDition?

Introduction to Programming - 6

;

The following message shows how to combine commands from different subsystems as well as within the same subsystem:

VOLTage:LEVel 20;PROTection 28;:CURRent:LEVel 3;PROTection:STATe ON

Note the use of the optional header LEVel to maintain the correct path within the voltage and current subsystems, and the use of the root specifier to move between subsystems.

Including Common Commands

You can combine common commands with system commands in the same message. Treat the common command as a message unit by separating it with a semicolon (the message unit separator). Common commands do not affect the header path; you may insert them anywhere in the message.

VOLTage:TRIGgered 17.5;:INITialize;*TRG OUTPut OFF;*RCL 2;OUTPut ON

Using Queries

Observe the following precautions with queries:

♦ Set up the proper number of variables for the returned data.

♦ Read back all the results of a query before sending another command to the dc source. Otherwise a

Query Interrupted error will occur and the unreturned data will be lost.

Types of SCPI Messages

There are two types of SCPI messages, program and response.

♦ A program message consists of one or more properly formatted SCPI commands sent from the

controller to the dc source. The message, which may be sent at any time, requests the dc source to perform some action.

♦ A response message consists of data in a specific SCPI format sent from the dc source to the

controller. The dc source sends the message only when commanded by a program message "query."

The following figure illustrates SCPI message structure:

Data

words

VOLT

word Separator

Messa

: LEV 20

Messa

e Unit Separators

Figure 6-2. Command Message Structure

e Unit

PROT 21

Indicator

Quer

: CURR?

Messa

Root S

<NL>

e Terminator

ecifier

FIG2-1.GA

6 - Introduction to Programming

The Message Unit

The simplest SCPI command is a single message unit consisting of a command header (or keyword) followed by a message terminator. The message unit may include a parameter after the header. The parameter can be numeric or a string.

ABORt<NL> VOLTage 20<NL>

Headers

Headers, also referred to as keywords, are instructions recognized by the dc source. Headers may be either in the long form or the short form. In the long form, the header is completely spelled out, such as VOLTAGE, STATUS, and DELAY. In the short form, the header has only the first three or four letters, such as VOLT, STAT, and DEL.

Query Indicator

Following a header with a question mark turns it into a query (VOLTage?, VOLTage:PROTection?). If a query contains a parameter, place the query indicator at the end of the last header.

VOLTage:PROTection? MAX

Message Unit Separator

When two or more message units are combined into a compound message, separate the units with a semicolon.

STATus:OPERation?;QUEStionable?

Root Specifier

When it precedes the first header of a message unit, the colon becomes the root specifier. It tells the command parser that this is the root or the top node of the command tree.

Message Terminator

A terminator informs SCPI that it has reached the end of a message. Three permitted messages terminators are:

♦ newline (<NL>), which is ASCII decimal 10 or hex 0A.

♦ end or identify (<END>)

♦ both of the above (<NL><END>).

In the examples of this guide, there is an assumed message terminator at the end of each message.

NOTE: All RS-232 response data sent by the dc source is terminated by the ASCII character pair

<carriage return><newline>. This differs from HP-IB response data, which is terminated by the single character <newline> with EOI asserted.

Introduction to Programming - 6

SCPI Data Formats

All data programmed to or returned from the dc source is ASCII. The data may be numerical or character string.

Numerical Data Formats

Symbol Data Form

Talking Formats

<NR1> Digits with an implied decimal point assumed at the right of the least-significant digit.

Examples: 273

<NR2>

<NR3>

Listening Formats

<Nrf>

<Nrf+>

<Bool>

Digits with an explicit decimal point. Example: .0273

Digits with an explicit decimal point and an exponent. Example: 2.73E+2

Extended format that includes <NR1>, <NR2> and <NR3>. Examples: 273 273.

2.73E2

Expanded decimal format that includes <NRf> and MIN MAX. Examples: 273 273.

2.73E2 MAX. MIN and MAX are the minimum and maximum limit values that are implicit in the range specification for the parameter.

Boolean Data. Example: 0 | 1 or ON | OFF

Suffixes and Multipliers

Class Suffix Unit Unit with Multiplier

Current A ampere MA (milliampere)

Amplitude V volt MV (millivolt)

Time S second MS (millisecond)

Common Multipliers

1E3 K kilo 1E-3 M milli 1E-6 U micro

Response Data Types

Character strings returned by query statements may take either of the following forms, depending on the length of the returned string:

<CRD> Character Response Data. Permits the return of character strings.

<AARD> Arbitrary ASCII Response Data. Permits the return of undelimited 7-bit ASCII. This data

type has an implied message terminator.

<SRD> String Response Data. Returns string parameters enclosed in double quotes.

6 - Introduction to Programming

SCPI Command Completion

SCPI commands sent to the dc source are processed either sequentially or in parallel. Sequential commands finish execution before a subsequent command begins. Parallel commands allow other commands to begin executing while the parallel command is still executing. Commands that affect trigger actions are among the parallel commands.

The *WAI, *OPC, and *OPC? common commands provide different ways of indicating when all transmitted commands, including any parallel ones, have completed their operations. The syntax and parameters for these commands are described in chapter 8. Some practical considerations for using these commands are as follows:

*WAI

*OPC?

*OPC

NOTE: The trigger subsystem must be in the Idle state in order for the status OPC bit to be true.

This prevents the dc source from processing subsequent commands until all pending operations are completed.

This places a 1 in the Output Queue when all pending operations have completed. Because it requires your program to read the returned value before executing the next program statement, *OPC? can be used to cause the controller to wait for commands to complete before proceeding with its program.

This sets the OPC status bit when all pending operations have completed. Since your program can read this status bit on an interrupt basis, *OPC allows subsequent commands to be executed.

Therefore, as far as triggers are concerned, OPC is false whenever the trigger subsystem is in the Initiated state.

Using Device Clear

You can send a device clear at any time abort a SCPI command that may be hanging up the HP-IB interface. The status registers, the error queue, and all configuration states are left unchanged when a device clear message is received. Device clear performs the following actions:

♦ The input and output buffers of the dc source are cleared.

♦ The dc source is prepared to accept a new command string.

The following statement shows how to send a device clear over the HP-IB interface using HP BASIC:

CLEAR 705 IEEE-488 Device Clear

The following statement shows how to send a device clear over the HP-IB interface using the HP-IB command library for C or QuickBASIC:

IOCLEAR (705)

NOTE: For RS-232 operation, sending a Break will perform the same operation as the IEE-488

device clear message.

Introduction to Programming - 6

RS-232 Troubleshooting

If you are having trouble communicating over the RS-232 interface, check the following:

♦ The computer and the dc source must be configured for the same baud rate, parity, number of data

bits, and flow control options. Note that the dc source is configured for 1 start bit and 1 stop bit (these values are fixed).

♦ The correct interface cables or adapters must be used, as described under RS-232 Connector. Note

that even if the cable has the proper connectors for your system, the internal wiring may be incorrect.

♦ The interface cable must be connected to the correct serial port on your computer (COM1, COM2,

etc.).

SCPI Conformance Information

The HP 66311A conforms to SCPI Version 1995.0.

SCPI Confirmed Commands

ABOR OUTP:PROT:DEL STAT:QUES:ENAB CAL:DATA OUT:PROT:STAT STAT:QUES:NTR CAL:STAT [SOUR]:CURR[:LEV][:IMM][:AMPL] STAT:QUES:PTR DISP[:WIND][:STAT] [SOUR]:CURR[:LEV]:TRIG[:AMPL] SYST:ERR? DISP[:WIND]:TEXT[:DATA] [SOUR]:CURR:PROT:STAT SYST:LANG INIT[:IMM]:SEQ | NAME [SOUR]:VOLT[:LEV][:IMM][:AMPL] SYST:VERS? INIT:CONT:SEQ | NAME [SOUR]:VOLT[:LEV]:TRIG[:AMPL] TRIG[:SEQ1 | :TRAN][:IMM] MEAS | FETC:ARR:CURR[:DC]? [SOUR]:VOLT:PROT TRIG[:SEQ1 | :TRAN]:SOUR MEAS | FETC:ARR:VOLT[:DC]? SENS:CURR[:DC]:RANG[:UPP] TRIG:SEQ2 | ACQ[:IMM] MEAS | FETC[:SCAL]:CURR[:DC]? SENS:FUNC TRIG:SEQ2 | ACQ:SOUR MEAS | FETC[:SCAL]:CURR:HIGH? SENS:SWE:OFFS:POIN TRIG:SEQ:DEF MEAS | FETC[:SCAL]:CURR:LOW? SENS:SWE:POIN *CLS MEAS | FETC[:SCAL]:CURR:MAX? SENS:SWE:TINT *ESE*ESE?*ESR? MEAS | FETC[:SCAL]:CURR:MIN? STAT:OPER[:EVEN]? *IDN? MEAS | FETC[:SCAL]:VOLT[:DC]? STAT:OPER:COND? *OPC*OPC?*OPT? MEAS | FETC[:SCAL]:VOLT:HIGH? STAT:OPER:ENAB *PSC*PSC? MEAS | FETC[:SCAL]:VOLT:LOW? STAT:OPER:NTR *RCL*RST MEAS | FETC[:SCAL]:VOLT:MAX? STAT:OPER:PTR *SAV*SRE*STB? MEAS | FETC[:SCAL]:VOLT:MIN? STAT:PRES *TRG*TST? OUTP[:STAT] STAT:QUES[:EVEN]? *WAI OUTP:PROT:CLE STAT:QUES:COND?

Non-SCPI Commands

Programming the DC Source

Introduction

This chapter contains examples on how to program your dc source. Simple examples show you how to program:

 output functions such as voltage and current

 internal and external triggers

 measurement functions

 the status and protection functions

NOTE: These examples in this chapter show which commands are used to perform a particular

function, but do not show the commands being used in any particular programming environment. Refer to Appendix D for some examples of SCPI commands in a specific programming environment.

Programming the Output

Power-on Initialization

When the dc source is first turned on, it wakes up with the output state set OFF. In this state the output voltage is set to 0. The following commands are given implicitly at power-on:

*RST *CLS STATus:PRESet *SRE 0 *ESE 0

*RST is a convenient way to program all parameters to a known state. Refer to the *RST command in chapter 8 to see how each programmable parameter is set by *RST. Refer to the *PSC command in chapter 8 for more information on the power-on initialization of the *ESE and the *SRE registers.

Enabling the Output

To enable the output, use the command:

OUTPut ON

7 - Programming the DC Source

Output Voltage

The output voltage is controlled with the VOLTage command. For example, to set the output voltage to 15 volts, use:

VOLTage 15

Maximum Voltage

The maximum rms output voltage that can be programmed can be queried with:

VOLTage? MAX

Overvoltage Protection

The dc source can be programmed to turn off its output if the output voltage exceeds a preset peak voltage limit. As explained in chapter 8, this protection feature is implemented with the following command:

VOLTage:PROTection <n>

where <n> is the voltage protection level.

NOTE: Use the VOLT:PROT:STAT 0 command to disable the overvoltage protection circuit if

its operation interferes with the proper operation of your phone test.

Output Current

All models have a programmable current function. The command to program the current is:

CURRent <n>

where <n> is the current limit in amperes.

If the load attempts to draw more current than the programmed limit, the output voltage is reduced to keep the current within the limit.

Maximum Current

The maximum output current that can be programmed can be queried with:

CURRent? MAX

Overcurrent Protection

The dc source can also be programmed to turn off its output if the current limit is reached. As explained in chapter 8, this protection feature is implemented the following command:

CURRent:PROTection:STATe ON | OFF

NOTE: Use the OUTP:PROT:DEL command to prevent momentary current limit conditions

caused by programmed output changes from tripping the overcurrent protection.

Programming the DC Source - 7

[

]

Triggering Output Changes

The dc source has two independent trigger systems. One is used for generating output changes, and the other is used for triggering measurements. This section describes the output trigger system. The measurement trigger system is described under "Triggering Measurements".

SCPI Triggering Nomenclature

In SCPI terms, trigger systems are called sequences. When more than one trigger system exists, they are differentiated by naming them SEQuence1 and SEQuence2. SEQuence1 is the transient trigger system and SEQuence2 is the measurement trigger system. The dc source uses aliases with more descriptive names for these sequences. These aliases can be used instead of the sequence forms.

Sequence Form Alias

SEQuence1 TRANsient SEQuence2 ACQuire

Output Trigger System Model

Figure 7-1 is a model of the output trigger system. The rectangular boxes represent states. The arrows show the transitions between states. These are labeled with the input or event that causes the transition to occur.

BORt

INITiate:CONTinuous OFF

INITiate:CONTinuous ON

IDLE STATE

INITiate

INITIATED STATE

TRIGGER RECEIVED

OUTPUT

LEVEL

CHANGE

:IMMediate

*RST *RCL

Figure 7-1. Model of Output Triggers

Setting the Voltage or Current Trigger Levels

To program output trigger levels, you must first specify a voltage or current trigger level that the output will go to once a trigger signal is received. Use the following commands to set the output trigger level:

VOLTage:TRIGgered <n> or CURRent:TRIGgered <n>

NOTE: Until they are programmed, trigger levels will be the same as the corresponding voltage

or current levels. For example, if a dc source is powered up and the voltage is programmed to 6, then the trigger level is also set to 6. Once you program a trigger level, it will stay at that value regardless of how you subsequently reprogram the voltage.

7 - Programming the DC Source

Initiating the Output Trigger System

When the dc source is turned on, the trigger subsystem is in the idle state. In this state, the trigger subsystem ignores all triggers. Sending the following commands at any time returns the trigger system to the idle state:

ABORt *RST *RCL

The INITiate commands move the trigger system from the idle state to the initiated state. This enables the dc source to receive triggers. To initiate for a single triggered action, use:

INITiate:SEQuence1 or INITiate:NAME TRANsient

After a trigger is received and the action completes, the trigger system will return to the idle state. Thus it will be necessary to initiate the system each time a triggered action is desired.

To keep the transient trigger system initiated for multiple actions without having to send an initiate command for each trigger, use:

INITiate:CONTinuous:SEQuence1 ON or INITiate:CONTinuous:NAME TRANsient, ON

Generating Triggers

You can only program output triggers over the HP-IB bus. Since BUS is the only trigger source for output triggers, the following command is provided for completeness only:

TRIGger:SOURce BUS

Single Triggers

After you have specified the appropriate trigger source, you can generate triggers by sending one of the following commands over the HP-IB:

TRIGger:IMMediate *TRG

a group execute trigger

When the trigger system enters the Output Change state upon receipt of a trigger (see figure 7-1), the triggered functions are set to their programmed trigger levels. When the triggered actions are completed, the trigger system returns to the idle state.

Multiple Triggers

When you have programmed INITiate:CONTinuous:SEQuence1 ON as previously discussed, the trigger system does not need to be initiated for each trigger; it responds to the next trigger as soon as it is received. When each triggered action completes, the trigger system returns to the initiated state to wait for the next trigger.

Programming the DC Source - 7

Making Measurements

The dc source has the ability to make several types of voltage or current measurements. These measurement capabilities are particularly useful for loads that draw current in pulses.

NOTE: Because there is only one measurement buffer, you cannot measure output voltage and

current simultaneously.

All measurements are performed by digitizing the instantaneous output voltage or current for a defined number of samples and sample interval, storing the results in a buffer, and then calculating the measured result. Many parameters of the measurement are programmable. These include the number of samples, the time interval between samples, and the method of triggering. Note that there is a tradeoff between these parameters and the speed, accuracy, and stability of the measurement in the presence of noise.

There are two ways to make measurements:

♦ Use the MEASure commands to immediately start acquiring new voltage or current data, and return

measurement calculations from this data as soon as the buffer is full. This is the easiest way to make measurements, since it requires no explicit trigger programming.

♦ Use an acquisition trigger to acquire the data as discussed under “Triggering Measurements”. Then

use the FETCh commands to return calculations from the data that was retrieved by the acquisition trigger. This method gives you the flexibility to synchronize the data acquisition with a transition in the output voltage or current. FETCh commands do not trigger the acquisition of new measurement data, but they can be used to return many different calculations from the data that was retrieved by the acquisition trigger. Note that if you take a voltage measurement, you can fetch only voltage data.

NOTE: For each MEASure form of the query, there is a corresponding FETCh query. FETCh

queries perform the same calculation as MEASure queries, but do not cause new data to be acquired.

Controlling Measurement Samples

You can vary both the number of data points in a measurement sample, as well as the time between samples. This is illustrated in Figure 7-2.

Figure 7-2. Commands that Control Measurement Time

7 - Programming the DC Source

When the instrument is turned on and at *RST, the output voltage or current sampling rate is 15.6 microseconds, and the sweep size is set to 2048 data points. This means that it takes about 32 milliseconds to fill up 2048 data points in the data buffer. Adding a command processing overhead of about 20 milliseconds results in a total measurement time of about 50 milliseconds per measurement. You can vary this data sampling rate with:

SENSe:SWEep:TINTerval <sample_period> SENSe:SWEep:POINts <points>

For example, to set the time interval to 46.8 microseconds per measurement with 1500 samples, use

SENSe:SWEep:TINTerval 46.8E-6;POINts 1500.

Note that reducing the number of sample points increases the speed of the measurement; however, the tradeoff is greater measureent uncertainty in the presence of noise..

Current Ranges and Measurement Detector

The dc source has two current measurement ranges. The command that controls the ranges is:

SENSe:CURRent:RANGe MIN | MAX

When the range is set to MIN, the maximum current that can be measured is 20 milliamperes. The crossover value of the high and low ranges is 20 milliamperes.

The dc source also has two measurement detectors. Check that the current detector is set to ACDC when measuring current pulses or other waveforms with a frequency content greater than a few kilohertz.

SENSe:CURRent:DETect ACDC

Select DC as the measurement detector if you are making only DC current measurements and you require a measurement offset better than 2mA on the High current measurement range. Note that this selection gives inaccurate results on current waveforms that have ac content.

SENSe:CURRent:DETect DC

Window Functions

The dc source lets you select from two measurement window functions: Hanning and Rectangular. To select a window function, use:

SENSe:WINDow: HANN | RECT

As shipped from the factory, the dc source measurement functions use a Hanning window. The Hanning window applies a cos measurements such as average and rms. This returns accurate data even if an integral number of waveform cycles are not captured, provided that at least three or more waveform cycles are in the measurement buffer. If there are only one or two waveform cycles, the Hanning window will not give accurate results.

weighting function to the data in the measurement buffer when computing

With a Rectangular window, no weighting function is applied to the data in the measurement buffer. However, to use the Rectangular window function to return accurate data for one or more waveform cycles, an integral number of of waveform cycles must be captured in the measurement buffer. This means that you must accurately know the waveform period beforehand. In this way you can chose the

Programming the DC Source - 7

sample interval and the number of data points so that and integral number of waveform cycles will end up in the measurement buffer.

Voltage and Current Measurements

The HP 66311A has a number of waveform measurement capabilities. The SCPI language MEASure and FETCh queries are used to return the various measurement parameters of voltage and current waveforms.

Average Measurements

To measure the average output voltage or current, use:

MEASure:VOLTage? or MEASure:CURRent?

Average voltage and current is measured by acquiring a number of readings at the selected time interval, applying the Hanning window function to the readings, and averaging the readings. Windowing is a signal conditioning process that reduces the error in average measurements made in the presence of periodic signals such as pulse current waveforms, which are generated when TDMA cellular phones are transmitting. The power-on and *RST sample interval and sweep size settings yield a data acquisition time of 32 milliseconds per measurement.

Ripple rejection is a function of the number of cycles of the ripple frequency contained in the acquisition window. More cycles in the acquisition window results in better ripple rejection. If you increase the data acquisition time for each measurement to 45 microseconds for example, this results in 5.53 cycles in the acquisition window at 60 Hz, for a ripple rejection of about 70 dB.

RMS Measurements

To read the rms content of a voltage or current waveform, use:

MEASure:VOLTage:ACDC? or MEASure:CURRent:ACDC?

This returns the total rms measurement.

Making rms or average measurements on ac waveforms for which a non-integral number of cycles of data has been acquired may result in measurement errors due to the last partial cycle of acquired data. The instrument reduces this error by using a Hanning window function when making the measurement. If the measurement readings vary from sample to sample, try increasing the data acquisition time to reduce measurement error.

Pulse Measurements

Use fetch queries to return pulse measurement data in the shortest time. The fetch functions do not trigger the acquisition of new measurement data, but are used to return different calculations from the data that was retrieved by the acquisition trigger. If you take a voltage measurement you can fetch only voltage data; if you take a current measurement you can fetch only current data, otherwise an error will occur.

The dc source has several measurement queries that return key parameters of pulse waveforms as shown in Figure 7-3.

7 - Programming the DC Source

FETC:CURR:MAX?

FETC:VOLT:MAX?

FETC:CURR:HIGH? FETC:VOLT:HIGH?

FETC:CURR:LOW?

DATA POINTS

FETC:VOLT:LOW?

FETC:CURR:MIN?

FETC:VOLT:MIN?

Figure 7-3. Measurement Commands Used to Return Pulse Data

Minimum and Maximum Measurements

To return the maximum or minimum value of a pulse or ac waveform use:

FETCh:VOLTage:MAXimum? or FETCh:VOLTage:MINimum? FETCh:CURRent:MAXimum? or FETCh:CURRent:MINimum?

High/Low Measurements

The value of the high level or low level of a pulse can also be measured. High and low level measurements are defined as follows: The instrument first measures the minimum and maximum data points of the pulse waveform. It then generates a histogram of the pulse waveform using 1024 bins between the maximum and minimum data points. The bin containing the most data points above the 50% point is the high bin. The bin containing the most data points below the 50% point is the low bin. The average of all the data points in the high bin is returned as the High level. The average of all the data points in the low bin is returned as the Low level. If no high or low bin contains more than 1.25% of the total number of acquired points, then the maximum or minimum value is returned by these queries.

To return the average value of the high bin, use:

FETCh:CURRent:HIGH? or FETCh:VOLTage:HIGH?

To return the average value of the low bin, use:

FETCh:CURRent:LOW? or FETCh:VOLTage:LOW?

Programming the DC Source - 7

[

]

Returning All Measurement Data From the Data Buffer

The MEASure:ARRay and FETCh:ARRay queries return all data values of the instantaneous voltage or current buffer. No weighting function is applied when returning the raw data from the array. The commands are:

MEASure:ARRay:CURRent? MEASure:ARRay:VOLTage?

Internally Triggered Measurements

You can use the data acquisition trigger system to synchronize the timing of the voltage and current data acquisition with a BUS or internal trigger source. Then use the FETCh commands to return different calculations from the data acquired by the measurement trigger.

SCPI Triggering Nomenclature

As previously explained under "Triggering Output Changes", the dc source uses the following sequence name and alias for the measurement trigger system. This alias can be used instead of the sequence form.

Sequence Form Alias

SEQuence2 ACQuire

Measurement Trigger System Model

Figure 7-4 is a model of the measurement trigger system. The rectangular boxes represent states. The arrows show the transitions between states. These are labeled with the input or event that causes the transition to occur.

IDLE STATE

INITIATED STATE

SENSe:SWEep:POINts

TRIGger:COUNt

COMPLETE?

YES

INITiate

TRIGGER RECEIVED

CQUIRED

:IMMediate

Figure 7-4. Model of Measurement Triggers

BORt *RST *RCL

7 - Programming the DC Source

Initiating the Measurement Trigger System

When the dc source is turned on, the trigger system is in the idle state. In this state, the trigger system ignores all triggers. Sending the following commands at any time returns the trigger system to the idle state:

ABORt *RST *RCL

The INITiate commands move the trigger system from the idle state to the initiated state. This enables the dc source to receive triggers. To initiate for a measurement trigger, use:

INITiate:SEQuence2 or INITiate:NAME ACQuire

After a trigger is received and the data acquisition completes, the trigger system will return to the idle state (unless multiple measurements are desired). Thus it will be necessary to initiate the system each time a triggered acquisition is desired.

NOTE: You cannot initiate measurement triggers continuously. Otherwise, the measurement data

in the data buffer would continuously be overwritten by each triggered measurement.

Selecting the Measurement Trigger Source

The trigger system is waiting for a trigger signal in the initiated state. Before you generate a trigger, you must select a trigger source. The following measurement trigger sources can be selected:

BUS INTernal -

To select HP-IB bus triggers (group execute trigger, device trigger, or *TRG command), use:

TRIGger:SEQuence2:SOURce BUS or TRIGger:ACQuire:SOURce BUS

To select internal triggers (measurements triggered off the output signal) use:

TRIGger:SEQuence2:SOURce INTernal or TRIGger:ACQuire:SOURce INTernal

selects HP-IB bus triggers. selects the dc source's output as the measurement trigger.

Generating Measurement Triggers

There is only one measurement converter in the dc source. Before you generate a measurement trigger, you must specify a measurement acquisition of either voltage or current. To specify a measurement acquisition use:

SENSe:FUNCtion "CURRent" or SENSe:FUNCtion "VOLTage"

Programming the DC Source - 7

Single Triggers

Providing that you have specified the appropriate trigger source and a measurement acquisition, you can generate triggers as follows:

HP-IB Triggers

Internal Triggers

Trigger occurs on rising edge

when signal crosses positive

hysteresis band limit

TRIG:ACQ:LEV:CURR <level> TRIG:ACQ:LEV:VOLT <level>

TRIG:ACQ:SLOP:CURR POS

TRIG:ACQ:SLOP:VOLT NEG

Figure 7-5. Commands Used to Control Measurement Triggers

Send one of the following commands over the HP-IB:

TRIGger:IMMediate (not affected by the trigger source setting) *TRG

a group execute trigger

To trigger off of the output signal, you must specify the output level that generates the trigger, the rising or falling edge of the slope, and a hysteresis to qualify trigger conditions. This is illustrated in figure 7-5.

Trigger occurs on falling edge

when signal crosses negative

hysteresis band limit

TRIG:ACQ:HYST:CURR <value>

TRIG:ACQ:HYST:VOLT <value>

TRIG:ACQ:SLOP:CURR NEG

TRIG:ACQ:SLOP:VOLT NEG

Measurement time = time interval X number of points

To specify the output level that will generate triggers for both positive- and negative-going signals use:

TRIGger:SEQuence2:LEVel:CURRent <value> or TRIGger:ACQuire:LEVel:CURRent <value>

To specify the slope on which triggering occurs use the following commands. You can specify a POSitive, a NEGative, or EITHer type of slope.

TRIGger:SEQuence2:SLOPe:CURRent <slope> or TRIGger:ACQuire:SLOPe:CURRent <slope>

To specify a hysteresis band to qualify the positive- or negative-going signal use:

TRIGger:SEQuence2:HYSTeresis:CURRent <value> or TRIGger:ACQuire:HYSTeresis:CURRent <value>

NOTE: When using internal triggers, do not INITiate the measurement until after you have

specified the slope, level, and hysteresis.

When the acquisition finishes, any of the FETCh queries can be used to return the results. Once the measurement trigger is initiated, if a FETCh query is sent before the data acquisition is triggered or before it is finished, the response data will be delayed until the trigger occurs and the acquisition completes. This may tie up the controller if the trigger condition does not occur immediately.

7 - Programming the DC Source

One way to wait for results without tying up the controller is to use the SCPI command completion commands. For example, you can send the *OPC command after INITialize, then occasionally poll the OPC status bit in the standard event status register for status completion while doing other tasks. You can also set up an SRQ condition on the OPC status bit going true, and do other tasks until an SRQ interrupt occurs.

Multiple Triggers

As shown in Figure 7-6, the dc source also has the ability to set up several measurements in succession.

trigger 1 trigger 2 trigger 3

trigger level

Measurement

(Measurement = time interval X # of points)

Measurement

TRIG:ACQ:COUN:VOLT 3 or TRIG:ACQ:COUN:CURR 3

Measurement

Figure 7-6. Multiple Measurements

To set up the trigger system for a number of sequential acquisitions use:

TRIGger:ACQuire:COUNt:CURRent <number> or TRIGger:ACQuire:COUNt:VOLTage <number>

With this setup, the instrument performs each acquisition sequentially, storing the digitized readings in the internal measurement buffer. It is only necessary to initialize the measurement once at the start; after each completed acquisition the instrument will wait for the next valid trigger condition to start another. When all measurements complete, use FETCh commands to return the data.

By varying the measurement parameters, you can accurately measure specific portions of an output pulse. For example, if you set the measurement time to match the pulse width, you can measure just the high level of a specific number of output pulses. If you increase the measurement time to include the entire waveform, you will return measurement data based on the entire waveform. To calculate the correct time interval for your measurement, simply divide the desired measurement time by the number of points or samples in the measurement.

NOTE: The total number of data points cannot exceed 4096. This means that the count

multiplied by the points in each measurement cannot exceed 4096; otherwise an error will occur.

Pre-event and Post-event Triggering

When a measurement is initiated, the dc source continuously samples either the instantaneous output voltage or current. As shown in figure 7-7, you can move the block of data being read into the acquisition

Programming the DC Source - 7

buffer with reference to the acquisition trigger. This permits pre-event or post-event data sampling.

Figure 7-7. Pre-event and Post-event Triggering

To offset the beginning of the acquisition buffer relative to the acquisition trigger, use:

SENSe:SWEep:OFFSet:POINts <offset>

The range for the offset is -4096 to 2,000,000,000 points. As shown in the figure, when the offset is negative, the values at the beginning of the data record represent samples taken prior to the trigger. When the value is 0, all of the values are taken after the trigger. Values greater than zero can be used to program a delay time from the receipt of the trigger until the data points that are entered into the buffer are valid. (Delay time = offset x sample period).

Programming the Status Registers

You can use status register programming to determine the operating condition of the dc source at any time. For example, you may program the dc source to generate an interrupt (assert SRQ) when an event such as a current limit occurs. When the interrupt occurs, your program can then act on the event in the appropriate fashion.

Figure 7-7 shows the status register structure of the dc source. Table 7-1 defines the status bits. The Standard Event, Status Byte, and Service Request Enable registers and the Output Queue perform standard HP-IB functions as defined in the IEEE 488.2 Standard Digital Interface for Programmable Instrumentation. The Operation Status and Questionable Status registers implement functions that are specific to the dc source.

Power-On Conditions

Refer to the *RST command description in chapter 8 for the power-on conditions of the status registers.

7 - Programming the DC Source

QUESTIONABLE STATUS

OCP

N.U.

Unreg

N.U.

MeasOvld

N.U.

OPC

N.U.

QYE

DDE

EXE

CME

N.U.

PON

CONDITION

5-8

1024

11-13

STANDARD E VENT STATUS

EVENT ENABLE

512

128

PTR/ NTR

44 4

512

1024

16384 16384 1638416384

128

EVENT

512

1024

LOGICAL OR

ENABLE

512

1024

OUTPU T QUEUE

DATA

LOGICAL OR

QUEUE

NOT

EMPTY

OFF

N.U.

QUES

MAV

ESB

MSS

OPER

OUTPut:DFI:SOURce

STATUS B YTE

0-2

FLT

SERVICE

REQUEST

ENABLE

128

LOGICAL OR

CAL

N.U.

WTG

N.U.

CC+

CC-

N.U.

1-4

6,7

12-15

CONDITION

256

512

1024

2048

OPERATION STATUS

PTR/NTR

256

512

1024

2048

EVENT

256

512

1024

2048

ENABLE

256

512

1024

2048

LOGICAL OR

Figure 7-7. DC Source Status Model

RQS

SERVICE

REQUEST

GENERATI ON

Table 7-1. Bit Configurations of Status Registers

Bit Signal Meaning

0 5 8 10 11

0 1 4 9 10 14

0 2 3 4 5 7

3 4 5 6

CAL WTG CV CC+ CC-

OV OCP OT RI Unreg MeasOvld

OPC QYE DDE EXE CME PON

QUES MAV ESB MSS RQS OPER

Operation Status Group The dc source is computing new calibration constants The dc source is waiting for a trigger The dc source is in constant voltage mode The dc source is in constant current mode The dc source is in negative constant current mode Questionable Status Group The overvoltage protection has tripped The overcurrent protection has tripped The overtemperature protection has tripped The remote inhibit state is active The output is unregulated Current measurement exceeded capability of low range Standard Event Status Group Operation complete Query error Device-dependent error Execution error Command error Power-on Status Byte and Service Request Enable Registers Questionable status summary bit Message Available summary bit Event Status Summary bit Master Status Summary bit Request Service bit Operation status summary bit

Programming the DC Source - 7

Operation Status Group

The Operation Status registers record signals that occur during normal operation. As shown below, the group consists of a Condition, PTR/NTR, Event, and Enable register. The outputs of the Operation Status register group are logically-ORed into the OPERation summary bit (7) of the Status Byte register.

Condition STAT:OPER:COND? A register that holds real-time status of the circuits being monitored.

It is a read-only register.

PTR Filter STAT:OPER:PTR <n> A positive transition filter that functions as described under

STAT:OPER:NTR|PTR commands in chapter 8. It is a read/write register.

NTR Filter STAT:OPER:NTR <n> A negative transition filter that functions as described under

STAT:OPER:NTR|PTR commands in chapter 8. It is a read/write register.

Event STAT:OPER:EVEN? A register that latches any condition that is passed through the PTR or

NTR filters. It is a read-only register that is cleared when read.

Enable

STAT:OPER:ENAB <n>

A register that functions as a mask for enabling specific bits from the Event register. It is a read/write register.

7 - Programming the DC Source

Questionable Status Group

The Questionable Status registers record signals that indicate abnormal operation of the dc source. As shown in figure 7-7, the group consists of the same type of registers as the Status Operation group. The outputs of the Questionable Status group are logically-ORed into the QUEStionable summary bit (3) of the Status Byte register.

Condition STAT:QUES:COND? A register that holds real-time status of the circuits being monitored. It

is a read-only register.

PTR Filter STAT:QUES:PTR <n> A positive transition filter that functions as described under

STAT:QUES:NTR|PTR commands in chapter 8. It is a read/write register.

NTR Filter STAT:QUES:NTR <n> A negative transition filter that functions as described under

STAT:QUES:NTR|PTR commands in chapter 8. It is a read/write register.

Event STAT:QUES:EVEN? A register that latches any condition that is passed through the PTR or

NTR filters. It is a read-only register that is cleared when read.

Enable STAT:QUES:ENAB <n> A register that functions as a mask for enabling specific bits from the

Event register. It is a read/write register..

Standard Event Status Group

This group consists of an Event register and an Enable register that are programmed by Common commands. The Standard Event event register latches events relating to instrument communication status (see figure 7-7). It is a read-only register that is cleared when read. The Standard Event enable register functions similarly to the enable registers of the Operation and Questionable status groups.

Command Action

*ESE *PSC ON *ESR?

programs specific bits in the Standard Event enable register. clears the Standard Event enable register at power-on. reads and clears the Standard Event event register.

The PON (Power On) Bit

The PON bit in the Standard Event event register is set whenever the dc source is turned on. The most common use for PON is to generate an SRQ at power-on following an unexpected loss of power. To do this, bit 7 of the Standard Event enable register must be set so that a power-on event registers in the ESB (Standard Event Summary Bit), bit 5 of the Service Request Enable register must be set to permit an SRQ to be generated, and *PSC OFF must be sent. The commands to accomplish these conditions are:

*PSC OFF *ESE 128 *SRE 32

Status Byte Register

This register summarizes the information from all other status groups as defined in the IEEE 488.2 Standard Digital Interface for Programmable Instrumentation. See Table 7-1 for the bit configuration.

Command Action

*STB? reads the data in the register but does not clear it (returns MSS in bit 6) serial poll clears RQS inside the register and returns it in bit position 6 of the response.

Programming the DC Source - 7

The MSS Bit

This is a real-time (unlatched) summary of all Status Byte register bits that are enabled by the Service Request Enable register. MSS is set whenever the dc source has one or more reasons for requesting service. *STB? reads the MSS in bit position 6 of the response but does not clear any of the bits in the Status Byte register.

The RQS Bit

The RQS bit is a latched version of the MSS bit. Whenever the dc source requests service, it sets the SRQ interrupt line true and latches RQS into bit 6 of the Status Byte register. When the controller does a serial poll, RQS is cleared inside the register and returned in bit position 6 of the response. The remaining bits of the Status Byte register are not disturbed.

The MAV Bit and Output Queue

The Output Queue is a first-in, first-out (FIFO) data register that stores dc source-to-controller messages until the controller reads them. Whenever the queue holds one or more bytes, it sets the MAV bit (4) of the Status Byte register.

Determining the Cause of a Service Interrupt

You can determine the reason for an SRQ by the following actions:

Step 1 Determine which summary bits are active. Use:

*STB? or serial poll

Step 2

Step 3 Remove the specific condition that caused the event. If this is not possible, the event

Read the corresponding Event register for each summary bit to determine which events caused the summary bit to be set. Use:

STATus:QUEStionable:EVENt? STATus:OPERation:EVENt? ESR?

When an Event register is read, it is cleared. This also clears the corresponding summary bit.

may be disabled by programming the corresponding bit of the status group Enable register or NTR|PTR filter. A faster way to prevent the interrupt is to disable the service request by programming the appropriate bit of the Service Request Enable register

Servicing Operation Status and Questionable Status Events

This example assumes you want a service request generated whenever the dc source switches to the CC (constant current) operating mode, or whenever the dc source's overvoltage, overcurrent, or overtemperature circuits have tripped. From figure 7-7, note the required path for a condition at bit 10 (CC) of the Operation Status register to set bit 6 (RQS) of the Status Byte register. Also note the required path for Questionable Status conditions at bits 0, 1, and 4 to generate a service request (RQS) at the Status Byte register. The required register programming is as follows:

7 - Programming the DC Source

Step 1 Program the Operation Status PTR register to allow a positive transition at bit 10 to

be latched into the Operation Status Event register, and allow the latched event to be summed into the Operation summary bit. Use:

STATus:OPERation:PTR 1024;ENABle 1024

Step 2

Step 3

Step 4

Program the Questionable Status PTR register to allow a positive transition at bits 0, 1, or 4 to be latched into the Questionable Status Event register, and allow the latched event to be summed into the Questionable summary bit. Use: STATus:QUEStionable:PTR 19;ENABle 19 (1 + 2 + 16 = 19)

Program the Service Request Enable register to allow both the Operation and the Questionable summary bits from the Status Byte register to generate RQS. Use: *SRE 136 (8 + 128 = 136)

When you service the request, read the event registers to determine which Operation Status and Questionable Status Event register bits are set, and clear the registers for the next event. Use:

STATus:OPERation:EVENt;QUEStionable:EVENt?

Monitoring Both Phases of a Status Transition

You can monitor a status signal for both its positive and negative transitions. For example, to generate RQS when the dc source either enters the CC+ (constant current) condition or leaves that condition, program the Operational Status PTR/NTR filter as follows:

STATus:OPERational:PTR 1024;NTR 1024

STATus:OPERational:ENABle 1024;*SRE 128

The PTR filter will cause the OPERational summary bit to set RQS when CC+ occurs. When the controller subsequently reads the event register with STATus:OPERational:EVEN?, the register is cleared. When CC+ subsequently goes false, the NTR filter causes the OPERational summary bit to again set RQS.

Inhibit/Fault Indicator

The remote inhibit(INH) and discrete fault(FLT) indicators are implemented through the respective INH and FLT connections on the rear panel. Refer to Table A-2 for the electrical parameters. Refer to Appendix E for a programming example.

Remote Inhibit (RI)

Remote inhibit is an external, chassis-referenced logic signal routed through the rear panel INH connection, which allows an external device to signal a fault. To select an operating modes for the remote inhibit signal, use:

OUTPut:RI:MODE LATChing | LIVE | OFF

Programming the DC Source - 7

Discrete Fault Indicator (DFI)

The discrete fault indicator is an open-collector logic signal connected to the rear panel FLT connection that can be used to signal external devices when a fault condition is detected. To select the internal fault source that drives this signal, use:

OUTPut:DFI:SOURce QUEStionable | OPERation | ESB | RQS | OFF

To enable or disable the DFI output, use:

OUTPut:DFI:STATe ON | OFF

Using the Inhibit/Fault Port as a Digital I/O

You can configure the inhibit/fault port to provide a digital input/output to be used with custom digital interface circuits or relay circuits. As shipped from the factory, the port is shipped for inhibit/fault operation. You can change the configuration of the port to operate as a general-purpose digital input output port with the following command:

[SOURce:]DIGital:FUNCtion RIDFi | DIGio

The following table shows the pin assignments of the mating plug when used in RI/DFI mode as well as Digital I/O mode. Refer to Table A-2 for the electrical characteristics of the port.

Pin FAULT/INHIBIT DIGITAL I/O Bit Weight

1 FLT Output OUT 0 0 2 FLT Output OUT 1 1 3 INH Input IN/OUT 2 2 4 INH Common Common not programmable

To program the digital I/O port use:

[SOURce:]DIGital:DATA <data>

where the data is an integer from 0 to 7 that sets pins 1 to 3 according to their binary weight. Refer to the DIGital:DATA command for more information.

Language Dictionary

Introduction

This section gives the syntax and parameters for all the IEEE 488.2 SCPI commands and the Common commands used by the dc source. It is assumed that you are familiar with the material in chapter 6, which explains the terms, symbols, and syntactical structures used here and gives an introduction to programming. You should also be familiar with chapter 5, in order to understand how the dc source functions.

The programming examples are simple applications of SCPI commands. Because the SCPI syntax remains the same for all programming languages, the examples given for each command are generic.

Syntax Forms

Parameters

Related Commands

Order of Presentation

Syntax definitions use the long form, but only short form headers (or "keywords") appear in the examples. Use the long form to help make your program selfdocumenting.

Most commands require a parameter and all queries will return a parameter. The range for a parameter may vary according to the model of dc source. When this is the case, refer to the Specifications table in the Appendix A.

Where appropriate, related commands or queries are included. These are listed because they are either directly related by function, or because reading about them will clarify or enhance your understanding of the original command or query.

The dictionary is organized according to the following functions: calibration, display, measurement, output, status, system, trigger, and common commands. Both the subsystem commands and the common commands that follow are arranged in alphabetical order under each heading.

Subsystem Commands

Subsystem commands are specific to functions. They can be a single command or a group of commands. The groups are comprised of commands that extend one or more levels below the root.

The subsystem command groups are arranged according to function: Calibration, Display, Measurement, Output, Status, System, and Trigger. Commands under each function are grouped alphabetically. Commands followed by a question mark (?) take only the query form. When commands take both the command and query form, this is noted in the syntax descriptions. Table 8-1 lists all of the subsystem commands in alphabetical order.

8 – Language Dictionary

Table 8-1. Subsystem Commands Syntax

ABORt CALibrate :CURRent [:SOURce] [:DC] [:POSitive] :NEGative :MEASure [:DC] :LOWRange :AC :DATA <n> :LEVel <level> :PASSword <n> :SAVE :STATE <bool> [,<n>] :VOLTage [:DC] :PROTection

DISPlay [:WINDow] [:STATe] <bool> :MODE <mode> :TEXT [:DATA] <string>

INITiate [:IMMediate] :SEQuence[<n>] :NAME <name> CONTinuous :SEQuence1, <bool> :NAME TRANsient, <bool>

MEASure | FETCh :ARRay :CURRent [:DC]? :VOLTage [:DC]? [:SCALar] :CURRent [:DC]? :ACDC? :HIGH? :LOW? :MAX? :MIN? :VOLTage [:DC]? :ACDC? :HIGH? :LOW? :MAX? :MIN?

Resets the trigger system to the Idle state

Calibrate positive output current and high current measurement range Calibrate negative output current

Calibrate low current measurement range Calibrate ac current measurement circuits Input a calibration measurement Advance to next calibration step (P1 | P2) Set calibration password Save new cal constants in non-volatile memory Enable or disable calibration mode

Calibrate output voltage and voltage readback Begin voltage protection calibration sequence

Enable/disable front panel display Set display mode (NORM | TEXT) Sets the text that is displayed

Initiate a specific numbered sequence (1 | 2) Initiate a specific named sequence (TRAN | ACQ)

Set continuous initialization Set continuous initialization

Returns the digitized instantaneous current Returns the digitized instantaneous voltage

Returns dc current Returns the total rms current (ac+dc) Returns the HIGH level of a current pulse Returns the LOW level of a current pulse Returns maximum current Returns minimum current Returns dc voltage Returns the total rms voltage (ac+dc) Returns the HIGH level of a voltage pulse Returns the LOW level of a voltage pulse Returns maximum voltage Returns minimum voltage

Table 8-1. Subsystem Commands Syntax (continued)

OUTPut [:STATe] <bool> :TYPE [:CAPacitance] <setting> :DFI [:STATe] <bool> :SOURce <source> :PON :STATe <state> :PROTection :CLEar :DELay <n> :RI :MODE <mode> SENSe :CURRent [:DC] RANGe [:UPPer] <n> :DETector <detector> :FUNCtion <function> :SWEep :OFFSet :POINts <n> :POINts <n> :TINTerval <n> :WINDow [:TYPE] <type> [SOURce:] CURRent [:LEVel] [:IMMediate][:AMPLitude] <n> :TRIGgered [:AMPLitude] <n> :PROTection :STATe <bool> DIGital :DATA [:VALue] <n> :FUNCtion <function> VOLTage [:LEVel] [:IMMediate][:AMPLitude] <n> :TRIGgered [:AMPLitude] <n> :PROTection [:LEVel] <n> :STATe <bool>

Language Dictionary - 8

Enables/disables the dc source output Sets output capacitor compensation (HIGH | LOW)

Enable/disable DFI output Selects event source (QUES | OPER | ESB | RQS | OFF)

Set power-on state (*RST | RCL0)

Reset latched protection Delay after programming/before protection

Sets remote inhibit input (LATC | LIVE | OFF)

Selects the high current measurement range Selects the current measurement detector (ACDC | DC) Configures the measurement sensor ("VOLT" | "CURR")

Defines the offset in the data sweep Define the number of data points in a sweep Sets the digitizer sample spacing Sets the measurement window function (HANN | RECT)

Sets the output current level Sets the triggered output current level

Enable/Disable current limit protection (ON

Sets and reads the digital control port Configures digital control port (RIDF | DIG)

Sets the dc voltage level Sets the transient voltage level

Sets the overvoltage protection threshold Enable/Disable overvoltage protection

8 – Language Dictionary

Table 8-1. Subsystem Commands Syntax (continued)

STATus :PRESet :OPERation [:EVENt]? :CONDition? :ENABle <n> :NTRansition<n> :PTRansition<n> :QUEStionable [:EVENt]? :CONDition? :ENABle <n> :NTRansition<n> :PTRansition<n> SYSTem :ERRor? :LANGuage <language> :VERSion? :LOCal :REMote :RWLock TRIGger :SEQuence2 | :ACQuire [:IMMediate] :COUNt :CURRent <n> :VOLTage <n> :HYSTeresis :CURRent <n> :VOLTage <n> :LEVel :CURRent <n> :VOLTage <n> :SLOPe :CURRent <slope> :VOLTage <slope> :SOURce <source> [:SEQuence1 | :TRANsient] [:IMMediate] :SOURce <source> :SEQuence1 :DEFine TRANsient :SEQuence2 :DEFine ACQuire

Presets all enable and transition registers to power-on

Returns the value of the event register Returns the value of the condition register Enables specific bits in the Event register Sets the Negative transition filter Sets the Positive transition filter

Returns the error number and error string Sets the programming language (SCPI | COMP) Returns the SCPI version number Go to local mode (for RS-232 operation) Go to remote mode (for RS-232 operation) Go to remote with local lockout (for RS-232 operation)

Triggers the measurement immediately

Sets the number of sweeps per current measurement Sets the number of sweeps per voltage measurement

Qualifies the trigger when measuring current Qualifies the trigger when measuring voltage

Sets the trigger level for measuring current Sets the trigger level for measuring voltage

Sets the triggered current slope (POS | NEG | EITH) Sets the triggered voltage slope (POS | NEG | EITH) Sets the trigger source (BUS | INT)

Triggers the output immediately Sets the trigger source (BUS)

Sets or queries the SEQ1 name

Sets or queries the SEQ2 name

Language Dictionary - 8

Common Commands

Common commands begin with an * and consist of three letters (command) or three letters and a ? (query). They are defined by the IEEE 488.2 standard to perform common interface functions. Common commands and queries are categorized under System, Status, or Trigger functions and are listed at the end of the chapter. The dc source responds to the following common commands:

Table 8-2. Common Commands Syntax

*CLS *ESE <n> *ESE? *ESR? *IDN? *OPC *OPC? *OPT? *PSC <bool> *PSC? *RCL <n> *RST *SAV <n> *SRE <n> *SRE? *STB? *TRG *TST? *WAI

Clear status Standard event status enable Return standard event status enable Return event status register Return instrument identification Enable "operation complete" bit in ESR Return a "1" when operation complete Return option number Power-on status clear state set/reset Return power-on status clear state Recall instrument state Reset Save instrument state Set service request enable register Return service request enable register Return status byte Trigger Perform selftest, then return result Hold off bus until all device commands done

Programming Parameters

The following table lists the output programming parameters.

Table 8-3. Output Programming Parameters

Parameter Value

[SOUR:]CURR[:LEV][:IMM] MAX and [SOUR:]CURR[:LEV]:TRIG MAX *RST Current Value 10% of MAX value [SOUR:]VOLT[:LEV][:IMM]MAX and [SOUR:]VOLT[:LEV]:TRIG MAX *RST Voltage Value 0 V [SOUR:]VOLT:PROT[:LEV] MAX 22 V *RST OVP Value MAX OUTP:PROT:DEL MAX 2,147,483.647 *RST Protection Delay Value 0.08 seconds SENS:CURR:RANG

*RST Current Range Value MAX

3.0712

15.535

Low range = 0 − 20 mA

High Range = 20 mA − MAX

8 – Language Dictionary

Calibration Commands

Calibration commands let you:

 Enable and disable the calibration mode  Change the calibration password  Calibrate the current and voltage programming and measurement, and store new calibration constants

in nonvolatile memory.

NOTE: If calibration mode has not been enabled with CALibrate:STATe, programming the

calibration commands will generate an error.

CALibrate:CURRent

This command initiates the calibration of the positive dc output current as well as the high-range current measurement circuit.

Command Syntax

Parameters

Examples

Related Commands

CALibrate:CURRent[:SOURce][:DC][:POSitive] None

CAL:CURR CAL:CURR:SOUR:DC:POS

CAL:CURR:NEG

CALibrate:CURRent:MEASure:LOWRange

This command initiates the calibration of the low-range current measurement circuit.

Command Syntax

Parameters

Examples

Related Commands

CALibrate:CURRent:MEASure[:DC]:LOWRange None

CAL:CURR:MEAS

CAL:CURR

CALibrate:CURRent:MEASure:AC

This command initiates the calibration of the high bandwidth (ac) measurement circuit.

Command Syntax

Parameters

Examples

CALibrate:CURRent:MEASure:AC None

CAL:CURR:MEAS:AC

CALibrate:CURRent:NEGative

This command initiates the calibration of the negative dc output current.

Command Syntax

Parameters

Examples

Related Commands

CALibrate:CURRent[:SOURce][:DC]:NEGative None

CAL:CURR:NEG CAL:CURR:SOUR:DC:NEG

CAL:CURR

Language Dictionary - 8

CALibrate:DATA

This command enters a calibration value that you obtain by reading an external meter. You must first select a calibration level (with CALibrate:LEVel) for the value being entered.

Command Syntax

Parameters

Unit

Examples

Related Commands

CALibrate:DATA<NRf> <external reading>

A (amperes) CAL:DATA 3222.3 MA CAL:DATA 5.000

CAL:STAT CAL:LEV

CALibrate:LEVel

This command selects the next point in the calibration sequence.

P1: the first calibration point P2: the second calibration point

Command Syntax

Parameters

Examples

CALibrate:LEVel <point> P1 | P2

CAL:LEV P2

CALibrate:PASSword

This command lets you change the calibration password. A new password is automatically stored in nonvolatile memory and does not have to be stored with CALibrate:SAVE.

If the password is set to 0, password protection is removed and the ability to enter the calibration mode is unrestricted.

Command Syntax

Parameters

Examples

Related Commands

CALibrate:PASScode<NRf> <model number> (default)

CAL:PASS 6812 CAL:PASS 6.1994

CAL:SAV

CALibrate:SAVE

This command saves any new calibration constants after a calibration procedure has been completed in nonvolatile memory. If CALibrate:STATe OFF is programmed without a CALibrate:SAVE, the previous calibration constants are restored..

Command Syntax

Parameters

Examples

Related Commands

CALibrate:SAVE None

CAL:SAVE

CAL:PASS CAL:STAT

8 – Language Dictionary

CALibrate:STATe

This command enables and disables calibration mode. The calibration mode must be enabled before the dc source will accept any other calibration commands.

The first parameter specifies the enabled or disabled state. The second parameter is the password. It is required if the calibration mode is being enabled and the existing password is not 0. If the password is not entered or is incorrect, an error is generated and the calibration mode remains disabled. The query statement returns only the state, not the password.

NOTE: Whenever the calibration state is changed from enabled to disabled, any new calibration

constants are lost unless they have been stored with CALibrate:SAVE.

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

Related Commands

CALibrate:STATe<bool>[,<NRf>] 0 | 1 | OFF | ON [,<password>] OFF

CAL:STAT 1,6812 CAL:STAT OFF

CALibrate:STATe? <NR1> CAL:PASS CAL:SAVE *RST

CALibrate:VOLTage

This command initiates the calibration of the output voltage and the voltage readback circuit.

Command Syntax

Parameters

Examples

CALibrate:VOLTage[:DC] None

CAL:VOLT CAL:VOLT:DC

CALibrate:VOLTage:PROTection

This command calibrates the overvoltage protection (OV) circuit. The dc source automatically performs the calibration. CALibrate:VOLTage:PROTection is a sequential command that takes several seconds to complete.

Command Syntax

Parameters

Examples

CALibrate:VOLTage:PROTection None

CAL:VOLT:PROT

Language Dictionary - 8

Display Commands

Display commands control the front panel display of the dc source.

DISPlay

This command turns the front panel display on or off. When off, the front panel display is blank. The display annunciators are not affected by this command.

Command Syntax

Parameters

*RST Value

Query Syntax

Returned Parameters

Related Commands

DISPlay:MODE

Examples

DISPlay[:WINDow][:STATe] <bool> 0 | 1| OFF| ON ON

DISP ON DISPLAY:STATE ON DISPlay[:WINDow][STATe]?

<NR1> 0 or 1 DISP:MODE DISP:TEXT *RST

Switches the display between its normal instrument functions and a mode in which it displays text sent by the user. Text messages are defined with the DISPlay:TEXT command.

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

Related Commands

DISPlay[:WINDow]:MODE <CRD> NORMal | TEXT NORM DISP:MODE NORM DISPLAY:MODE TEXT DISPlay[:WINDow]:MODE? <CRD> NORMAL or TEXT DISP DISP:TEXT *RST

DISPlay:TEXT

This command sends character strings to the display when the display mode is set to TEXT. The character string is case-sensitive and must be enclosed in either single (‘) or double (“) quotes. The display is capable of showing up to 14 characters. Strings exceeding 14 characters will be truncated.

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

Related Commands

DISPlay[:WINDow]:TEXT [:DATA] <display_string> <display string> null string

DISP:TEXT "DEFAULT_MODE"

DISPlay[:WINDow]:TEXT? <STR> (Last programmed text string) DISP DISP:MODE

8 – Language Dictionary

Measurement Commands

Measurement commands consist of measure and sense commands.

Measure commands measure the output voltage or current. Measurements are performed by digitizing the instantaneous output voltage or current for a specified number of samples, storing the results in a buffer, and calculating the measured result. Two types of measurement commands are available: MEASure and FETCh. MEASure triggers the acquisition of new data before returning the reading; FETCh returns a reading computed from previously acquired data. If you take a voltage measurement, you can fetch only voltage data.

♦ Use MEASure when the measurement does not need to be synchronized with any other event. ♦ Use FETCh when it is important that the measurement be synchronized with either a trigger or with a

particular part of the output waveform.

Sense commands control the current measurement range, the bandwidth detector of the dc source, and the data acquisition sequence.

MEASure:ARRay:CURRent? FETCh:ARRay:CURRent?

These queries return an array containing the instantaneous output current in amperes. The output voltage or output current are digitized whenever a measure command is given or whenever an acquire trigger occurs. The time interval is set by SENSe:SWEep:TINTerval. The position of the trigger relative to the beginning of the data buffer is determined by SENSe:SWEep:OFFSet. The number of points returned is set by SENSe:SWEep:POINts.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure:ARRay:CURRent[:DC]? FETCh:ARRay:CURRent[:DC]? None

MEAS:ARR:CURR? FETC:ARR:CURR?

<NR3> [,<NR3>] SENS:SWE:TINT SENS:SWE:OFFS SENS:SWE:POIN

MEASure:ARRay:VOLTage? FETCh:ARRay:VOLTage?

These queries return an array containing the instantaneous output voltage in volts. The output voltage or output current are digitized whenever a measure command is given or whenever an acquire trigger occurs. The time interval is set by SENSe:SWEep:TINTerval. The position of the trigger relative to the beginning of the data buffer is determined by SENSe:SWEep:OFFSet. The number of points returned is set by SENSe:SWEep:POINts.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure:ARRay:VOLTage[:DC]? FETCh:ARRay:VOLTage[:DC]? None

MEAS:ARR:VOLT? FETC:ARR:VOLT?

<NR3> [,<NR3>] SENS:SWE:TINT SENS:SWE:OFFS SENS:SWE:POIN

MEASure:CURRent? FETCh:CURRent?

These queries return the dc output current.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:CURRent[:DC]? FETCh[:SCALar]:CURRent[:DC]? None

MEAS:CURR? MEAS:CURR:DC?

<NR3> MEAS:VOLT?

MEASure:CURRent:ACDC? FETCh:CURRent:ACDC?

These queries return the ac+dc rms output current.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:CURRent:ACDC? FETCh[:SCALar]:CURRent:ACDC? None

MEAS:CURR:ACDC? FETC:CURR:ACDC?

<NR3> MEAS:VOLT:ACDC?

Language Dictionary - 8

MEASure:CURRent:HIGH? FETCh:CURRent:HIGH?

These queries return the High level current of a current pulse waveform. The instrument first measures the minimum and maximum data points of the pulse waveform. It then generates a histogram of the pulse waveform using 1024 bins between the maximum and minimum data points. The bin containing the most data points above the 50% point is the high bin. The average of all the data points in the high bin is returned as the High level. If no high bin contains more than 1.25% of the total number of acquired points, then the maximum value is returned by these queries.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:CURRent:HIGH? FETCh[:SCALar]:CURRent:HIGH? None

MEAS:CURR:HIGH? FETC:CURR:HIGH?

<NR3> MEAS:CURR:LOW? CALC:REF:HIGH

8 – Language Dictionary

MEASure:CURRent:LOW? FETCh:CURRent:LOW?

These queries return the Low level current of a current pulse waveform. The instrument first measures the minimum and maximum data points of the pulse waveform. It then generates a histogram of the pulse waveform using 1024 bins between the maximum and minimum data points. The bin containing the most data points below the 50% point is the low bin. The average of all the data points in the low bin is returned as the Low level. If no low bin contains more than 1.25% of the total number of acquired points, then the minimum value is returned by these queries.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:CURRent:LOW? FETCh[:SCALar]:CURRent:LOW? None

MEAS:CURR:LOW? FETC:CURR:LOW?

<NR3> MEAS:CURR:HIGH? CALC:REF:LOW

MEASure:CURRent:MAXimum? FETCh:CURRent: MAXimum?

These queries return the maximum output current.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:CURRent:MAXimum? FETCh[:SCALar]:CURRent:MAXimum? None

MEAS:CURR:MAX? FETC:CURR:MAX?

<NR3> MEAS:CURR:MIN?

MEASure:CURRent:MINimum? FETCh:CURRent:MINimum?

These queries return the minimum output current.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:CURRent:MINimum? FETCh[:SCALar]:CURRent:MINimum? None

MEAS:CURR:MIN? FETC:CURR:MIN?

<NR3> MEAS:CURR:MAX?

MEASure:VOLTage? FETCh:VOLTage?

These queries return the dc output voltage.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:VOLTage[:DC]? MEASure[:SCALar]:VOLTage[:DC]? None

MEAS:VOLT? FETC:VOLT:DC?

<NR3> MEAS:CURR?

MEASure:VOLTage:ACDC? FETCh:VOLTage:ACDC?

These queries return the ac+dc rms output voltage.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:VOLTage:ACDC? FETCh[:SCALar]:VOLTage:ACDC? None

MEAS:VOLT:ACDC? FETC:VOLT:ACDC?

<NR3> MEAS:CURR:ACDC?

Language Dictionary - 8

MEASure:VOLTage:HIGH? FETCh:VOLTage:HIGH?

These queries return the High level voltage of a voltage pulse waveform. The instrument first measures the minimum and maximum data points of the pulse waveform. It then generates a histogram of the pulse waveform using 1024 bins between the maximum and minimum data points. The bin containing the most data points above the 50% point is the high bin. The average of all the data points in the high bin is returned as the High level. If no high bin contains more than 1.25% of the total number of acquired points, then the maximum value is returned by these queries.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:VOLTage:HIGH? FETCh[:SCALar]:VOLTage:HIGH? None

MEAS:VOLT:HIGH? FETC:VOLT:HIGH?

<NR3> MEAS:VOLT:LOW? CALC:REF:HIGH

8 – Language Dictionary

MEASure:VOLTage:LOW? FETCh:VOLTage:LOW?

These queries return the Low level voltage of a voltage pulse waveform. The instrument first measures the minimum and maximum data points of the pulse waveform. It then generates a histogram of the pulse waveform using 1024 bins between the maximum and minimum data points. The bin containing the most data points below the 50% point is the low bin. The average of all the data points in the low bin is returned as the Low level. If no low bin contains more than 1.25% of the total number of acquired points, then the minimum value is returned by these queries.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:VOLTage:LOW? FETCh[:SCALar]:VOLTage:LOW? None

MEAS:VOLT:LOW? FETC:VOLT:LOW?

<NR3> MEAS:VOLT:HIGH? CALC:REF:LOW

MEASure:VOLTage:MAXimum? FETCh:VOLTage:MAXimum?

These queries return the maximum output voltage.

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:VOLTage:MAXimum? FETCh[:SCALar]:VOLTage:MAXimum? None

MEAS:VOLT:MAX? FETC:VOLT:MAX?

<NR3> MEAS:VOLT:MIN?

MEASure:VOLTage:MINimum? FETCh:VOLTage:MINimum?

These queries return the minimum output voltage..

Query Syntax

Parameters

Examples

Returned Parameters

Related Commands

MEASure[:SCALar]:VOLTage:MINimum? FETCh[:SCALar]:VOLTage:MINimum? None

MEAS:VOLT:MIN? FETC:VOLT:MIN?

<NR3> MEAS:VOLT:MAX?

Language Dictionary - 8

SENSe:CURRent:DETector

This command lets you select the type of detector used for output current measuremants. Two choices for detecting current measurements are available:

ACDC

NOTE: This command only applies to the High current measurement range.

This is the preferred choice for all dynamic current measurements. When ACDC is selected, the measured output current includes the current that flows in the instrument's output capacitor. It is especially important to use ACDC detection when measuring pulse or other waveforms with frequency contents greater than several kilohertz.

Select DC only if you are making dc current measurements and you require a dc measurement offset accuracy better than 2mA on the High current measurement range. When DC is selected, the component of output current that is supplied by the instrument's output filter is not sensed. Note that this selection gives inaccurate results on current waveforms with frequency contents greater than several kilohertz.

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

SENSe:CURRent:DETector <detector> ACDC or DC ACDC

SENS:CURR:DET ACDC SENS:CURR:DET DC

SENSe:CURRent:DETector? <CRD>

SENSe:CURRent:RANGe

This command selects the dc current measurement range. All models have two current measurement ranges:

High Range: 0 through MAX (see Table 8-3) Low Range: 0 through 0.02 A (all models)

The High range covers the full current measurement capability of the instrument. The Low range measures currents up to a maximum of 20 mA. This increases the low current measurement sensitivity for greater accuracy and resolution. The value that you program with SENSe:CURRent:RANGe must be the maximum current that you expect to measure. The instrument will select the range that gives the best resolution. The crossover value is 20 mA. When queried, the returned value is the maximum current that can be measured on the range that is presently set.

Command Syntax

Parameters

Unit

*RST Value

Examples

Query Syntax

Returned Parameters

SENSe:CURRent[:DC]:RANGe[:UPPer] <NRf+> 0 through MAX (see table 8-3) A (amperes) MAX (high range)

SENS:CURR:RANG 4.0

SENSe:CURRent:RANGe? <NR3>

8 – Language Dictionary

SENSe:FUNCtion

This command configures the measurement sensor to measure either voltage or current when an acquire trigger is used. The query returns the function setting, either VOLT or CURR.

Command Syntax

Parameters

Examples

Query Syntax

Returned Parameters

SENSe:FUNCtion <function> "VOLTage" | "CURRent"

SENS:FUNC "VOLT"

SENSe:FUNCtion? <SRD>

SENSe:SWEep:OFFSet:POINts

This command defines the offset in a data sweep when an acquire trigger is used. Negative values represent data samples taken prior to the trigger.

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

Related Commands

SENSe:SWEep:OFFSet:POINts <NRf+>

-4095 through 2,000,000,000 0

SENS:SWE:OFFS:POIN -2047

SENSe:SWEep:OFFSet:POINts? <NR3> SENS:SWE:TINT SENS:SWE:POIN MEAS:ARR

SENSe:SWEep:POINts

This command defines the number of points in a data sweep.

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

Related Commands

SENSe:SWEep:POINts<NRf+> 1 through 4096 2048

SENS:SWE:POIN 1024

SENSe:SWEep:POINts? <NR3> SENS:SWE:TINT SENS:SWE:OFFS MEAS:ARR

SENSe:SWEep:TINTerval

This command defines the time period between samples

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

Related Commands

SENSe:SWEep:TINTerval<NRf+>

15.6 microseconds through 31200 seconds

15.6 microseconds

SENS:SWE:TINT 31.2E-6

SENSe:SWEep:TINTerval? <NR3> SENS:SWE:POIN SENS:SWE:OFFS MEAS:ARR

Language Dictionary - 8

SENSe:WINDow

This command sets the window function that is used in output measurement calculations. The following functions can be selected:

HANNing

A signal conditioning window that reduces errors in dc and rms measurement calculations in the presence of periodic signals such as line ripple. It also reduces jitter when measuring successive pulse waveforms. The Hanning window multiplies each point in the measurement sample by the function

cosine

. Do not use the Hanning window when measuring single-shot pulse

waveforms.

RECTangular

A window that returns measurement calculations without any signal conditioning. This window may be used for pulse measurements where the exact period of the pulse waveform is known and the measurement interval can be set accordingly using the SENSe:SWEep:TINTerval command.

NOTE: Neither window function alters the instantaneous voltage or current data returned in the

measurement array.

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

SENSe:WINDow[:TYPE] <type> HANNing | RECTangular HANNing

SENS:WIND RECT

SENSe:WINDow[:TYPE]? <CRD>

8 – Language Dictionary

Output Commands

Output commands consist of output and source commands.

Output commands control the output and digital port functions. Source commands program the actual voltage, current, and digital port output.

OUTPut

This command enables or disables the dc source output. The state of a disabled output is a condition of zero output voltage and a model-dependent minimum source current (see *RST).

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

Related Commands

OUTPut:DFI

OUTPut[:STATe] <bool> 0 | OFF | 1 | ON 0

OUTP 1 OUTPUT:STATE ON

OUTPut[:STATe]? <NR1>0 or 1 *RST *RCL *SAV

This command enables or disables the discrete fault indicator (DFI) output from the dc source.

Command Syntax

Parameters

*RST Value

Examples

Query Syntax

Returned Parameters

Related Commands

OUTPut:DFI[:STATe] <bool> 0 | 1 | OFF | ON OFF

OUTP:DFI 1 OUTP:DFI ON

OUTPut:DFI[:STATe]? 0 | 1 OUTP:DFI:SOUR

OUTPut:DFI:SOURce

This command selects the source for discrete fault indicator (DFI) events. The choices are:

QUEStionable OPERation ESB RQS OFF

Command Syntax

Returned Parameters

Related Commands

selects the Questionable event summary bit (bit 3 of the Status Byte Register) selects the Operation Event summary bit (bit 7 of the Status Byte Register) selects the Standard Event summary bit (bit 5 of the Status Byte Register) selects the Request Service bit (bit 6 of the Status Byte Register) selects no DFI source

OUTP:DFI:SOUR <source>

Parameters

*RST Value

Examples

Query Syntax

QUES | OPER | ESB | RQS | OFF OFF

OUTP:DFI:SOUR OPER OUTPut:DFI:SOUR?

<CRD> OUTP:DFI

Language Dictionary - 8

OUTPut:PON:STATe

This command selects the power-on state of the dc source. This information is saved in non-volatile memory. The following states can be selected:

RST

RCL0

Returned Parameters

Sets the power-on state to *RST. Refer to the *RST command as described in this chapter for more information. Sets the power-on state to *RCL 0. Refer to the *RCL command as described in this chapter for more information.

Command Syntax

Parameters

Examples

Query Syntax

Related Commands

OUTPut:PON:STATe <state> RST | RCL0

OUTP:PON:STAT RST

OUTPut:PON:STATe? <CRD> *RST *RCL

OUTPut:PROTection:CLEar

This command clears the latch that disables the output when an overvoltage, overcurrent, overtemperature, or remote inhibit status condition is detected. All conditions that generate the fault must be removed before the latch can be cleared. The output is then restored to the state it was in before the fault condition occurred.

Command Syntax

Parameters

Examples

Related Commands

OUTPut:PROTection:CLEar None

OUTP:PROT:CLE

OUTP:PROT:DEL *RCL *SAV

OUTPut:PROTection:DELay

This command sets the time between the programming of an output change that produces a constant current condition (CC) and the recording of that condition by the Operation Status Condition register. The delay prevents the momentary changes in status that can occur during reprogramming from being registered as events by the status subsystem. Since the constant current condition is used to trigger overcurrent protection (OCP), this command also delays OCP. Overvoltage protection is not affected by this command.

Command Syntax

Parameters

Unit

*RST Value

Examples

Query Syntax

Returned Parameters

Related Commands

OUTPut:PROTection:DELay <NRf+> 0 to 2,147,483.647 seconds

0.08 (Normal)

OUTP:PROT:DEL 75E-1

OUTPut:PROTection:DELay? <NR3> OUTP:PROT:CLE *RCL *SAV

Agilent 66311A User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual