Tektronix 3910 User manual

ordains

Publication Date: June 1991
Document Number: 3910-900-01 Rev. A

perating

nformation

WARRANTY

Keithley Instruments, Inc. warrants this product to be free from defects in material and workmanship for a
period of 1 year from date of shipment.

Keithley Instruments, Inc. warrants the following items for 90 days from the date of shipment: probes, cables,
rechargeable batteries, diskettes, and documentation.

During the warranty period, we will, at our option, either repair or replace any product that proves to be de­fective.

To exercise this warranty, write or call your local Keithley representative, or contact Keithley headquarters in
Cleveland, Ohio. You will be given prompt assistance and return instructions. Send the product, transporta­tion prepaid, to the indicated service facility. Repairs will be made and the product returned, transportation
prepaid. Repaired or replaced products are warranted for the balance of the original warranty period, or at
least 90 days.

LIMITATION OF WARRANTY

This warranty does not apply to defects resulting from product modification without Keithley’s express writ­ten consent, or misuse of any product or part. This warranty also does not apply to fuses, software, non-re­chargeable batteries, damage from battery leakage, or problems arising from normal wear or failure to follow
instructions.

THIS WARRANTY IS IN LIEU OF ALL OTHER WARRAN TIES, EXPRESSED OR IMPLIED, INCLUDING
ANY IMPLIED WARRANTY OF MERCHANTABILIIY OR FlTNESS FOR A PARTICULAR USE. THE
REMEDIES PROVIDED HEREIN ARE BUYERS SOLE AND EXCLUSIVE REMEDIES.

NEITHER KEITHLEY INSTRUMENTS, INC. NOR ANY OF ITS EMPLOYEES SHALL BE LIABLE FOR
ANY DIRECT, INDIRECT, SPECIAL, INCIDENTAL OR CONSEQUENTIAL DAMAGES ARISING OUT
OF THE USE OF ITS INSTRUMENTS AND SOFIWARE EVEN IF KEITHLEY INSTRUMENTS, INC., HAS
BEEN ADVISED IN ADVANCE OF THE POSSIBILITY OF SUCH DAMAGES. SUCH EXCLUDED DAM­AGES SHALL INCLUDE, BUT ARE NOT LIMITED TO: COSTS OF REMOVAL AND INSTALLATION,
LOSSES SUSTAINED AS THE RESULT OF INJURY TO ANY PERSON, OR DAMAGE TO PROPERTY.

INSTRUMENTS

Instruments Division, Keithley Instruments, Inc. l 28775 Aurora

WEST GERMANY:

GREAT BRITAIN:
FRANCE Keithky Instruments SARL -3 Allee des Garays l B.P. 60.91124 P&iseau/Z.L l I-6-0115 155 l Telex: 600 933 l Fax: l-6-0117726
NEIXERLANDS: Keithley Instruments BV l Avehgen West 49 l 4202 MS Gorinchem l P.O. Box 559 l 4200 AN Gorinciwn l 01830-35333 l Telex: 24 684. Fax: [phone]
SWITZERLAND:
AUSTRIA: Keithley Instruments GesmbH L Rosenhugelstrasse 12 l A-1120 Vienna l (0222) CC4 65 48 l Telex: 131677 l Fax: [phone]
ITALY: Keithky Instruments SRL l Vi&S. Giiignano 4/A 0 20146 Milano l 02-4120360 or 02-4156540 l Fax M-4121249

Keithky Instruments GmbH l Landsbugers&. 65 l D-8034 Gemwring l 089-??49307-0 l Telex: 52-12160 l Fax: 089+?4930759
Keithky Instmments, Ltd. l The Mnster l 58, Portman Road l Reading, Berkshire RG 3 IEA l 01144 734 575 666 l Fax [phone]

Keithky Instruments SA l Kriesbachstr. 4 l 8600 Dubendorf l 01-821-V444 l Telex: 828 472 l Fax: [phone]

Road l Cleveland, Ohio 44139 l [phone] l Fax: [phone]

Operator’s Manual

Model 3910

Function Synthesizer

01991, Keithley Instruments, Inc.

All Rights Reserved

Instruments Division

Cleveland, Ohio, U. S. A.

document Number: 3910-900-01

All Keithley product names are trademarks or registered trademarks of Keithley Instruments, Inc.
Other brand and product names are trademarks or registered trademarks of their respective holders.

Safety Precautions

The following safety precautions should be observed before using the Model 3910 Function Synthesizer and any associ­ated instruments.

This instrument is intended for use by qualified personnel who recognize shock hazards and are familiar with the safety
precautions required to avoid possible injury. Read over this manual carefully before using the instrument.

Exercise extreme caution when a shock hazard is present at the test circuit. The American National Standards Institute

(ANSI) states that a shock hazard exists when voltage levels greater than 30V rms or 42.4V peak are present. A good

safety practice is to expect that hazardous voltage is present in any unknown circuit before measuring.

Inspect the connecting cables and test leads for possible wear, cracks, or breaks before each use.

For maximum safety, do not touch the test cables or any instruments while power is applied to the circuit under test.
Turn off the power and discharge any capacitors before connecting or disconnecting cables from the instrument.

Do not touch any object which could provide a current path to the common side of the circuit under test or power line
(earth) ground. Always make measurements with dry hands while standing on a dry, insulated surface capable of with­standing the voltage being measured.

Instrumentation and

accessories

should not be connected to humans.

Table of Contents

SECTION 1

1.1

1.2

1.3

1.4

1.5

1.6

1.6.1

1.6.2

1.63

1.6.4

1.7

1.8

- General Information

INTRODUCTION
FEATURES
WARRANTY INFORMATION
MANUALADDENDA

sAFETyTERMsANDsyMBoLs...........................................:

UNPACKlNGANDREPACKJNG

Unpacking
Shipment Contents
Operatofsb.nual

Repacking For Shipment
OPTIONALACCESSORIES
SPECIFICATIONS

...................................................................

.................................................................

SECTION 2 - Getting

2.1

2.2

2.2.1

2.2.2

2.3

2.3.1

2.3.2

2.3.3

2.4

2.5

2.5.1

2.5.2

2.5.3

INTRODUCTION
INSTALLATION

Installation Location

cooling

LINEPOWERSUPPLY.................,...................~

LINE Voltage Selector Switch ...................................................

Line Receptacle Connection .....................................................

LineFuse

HANDLING PRECAUTIONS .....................................................

BASICOPERATION

Front Panel Summary .........................................................

Typical Test Connections ......................................................

OperatingExamples

....................................................................

..................................................................

..............................................................

....................................................

..........................................................

.................................................

...........................................................

...........................................................

.......................................................

......................................................

.............................................................

Started

..............................................................

..............................................................

..................

............................................................

..........................................................

..C .....................................

.....................

l-1
l-l
1-2
l-2

...... 1-2

1-2
1-2
1-2
1-2
l-2
1-3
l-3

2-1
2-l
2-l
2-l
2-2
2-2
2-2
2-2
2-2
2-3
2-3
2-3
2-4

SECTION 3

3.1

3.2

3.2.1

3.2.2

3.3

3.3.1

3.3.2

3.4

3.5

3.5.1

INTRODUCTION

FRONT PANEL AND REAR PANEL DESCRIPTION ...................................

Front Panel Description

RearPanelDescription

INPUT AND OUTPUT CONNECTIONS ............................................

InputConnection

OutputConnections
STARTUP
OPERATING PROCEDURES

ErrorCodes

- Operation

..............................................................

........................................................

........................................................

............................................................

..........................................................

....................................................................

.....................................................

................................................................

3-1
3-l
3-1
3-4
3-5
3-5
3-5
3-6
3-7
3-7

’ 35.2 FrequencySetting

3.5.3 OutputAmplitude

3.5.4

3.5.5 Waveform Selection, Square-Wave Duty Cycle, and Synchronous Output

3.5.6 OscillationMode

3.5.7

DCOffset

Trigger Parameters

..................................................................

............................................................

...........................................................

.............................................................

........................................................... 3-11

..................

‘3-7

3-8
3-8
3-8

3-9

SECTION

4.1 INTRODUCTION

4.1.1 GPIBOverview

4.1.2 Major GPIB Specifications

4.1.3 Bus Line Signals and Operation

4.1.4 GPIBHandshaking

4.1.5

4.1.6

4.1.7 Basic Listener Functions

4.1.8 BasicControllerFunctions

4.1.9 Multi-line Interface Messages

4.2

4.2.1

4.2.2 Specifications

4.3 MODEL 3910 PROGRAM CODES

4.4 TYPICAL EXECUTION TIMES

4.5

4 - GPIB Interface

..............................................................

..............................................................

......................................................

...........................................................

Data Transfer Example
BasicTalkerFunctions

OVERVIEW OF MODEL 3910 GPIB INTERFACE

Introduction

SAMPLEPROGRAMS

................................................................

...............................................................

........................................................

.........................................................

.......................................................

......................................................

.................................................... 4-12

..........................................................

.................................................. 4-1

...................................................

......................................

..................................................

4-l
4-1
4-1

4-2
4-3
4-3

4-3
4-3
4-3

4-6
4-6
4-6

4-9

4-13

List of Illustrations

SECTION 2 -

Figure 2-1
Figure 2-2

SECTION 3

Figure 3-1
Figure 3-2
Figure 3-3
Figure 3-4
Figure 3-5

Figure 3-6
Figure 3-7
Figure 3-8

SECTION 4

Figure 4-1
Figure 4-2 Handshake Timing Diagram
Figure 4-3
Figure 44

Getting Started

Frontpanelsummary...............................................,...... 2-3

TypicalConnections . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

- Operation

Model 3910 Front Panel
Mode13910RearPanel
LogicInputCircuit

oLltputCircuit
Phase Relationship between FCTN OUT Waveform and SYNC OUT
Relationship between Trigger Signal and Oscillation in TRIG Mode
Relationship between Trigger Signal and Oscillation in GATE Mode
Definition of Phase of each Waveform

...........................................................

..................................................... 3-2

.....................................................

........................................................

- GPIB Interface

Interface Connector

Data Transfer Example

ProgramCodeSyntax ......................................................

.......................................................

.....................................................

2-4

3-4
3-5

3-6

...................

....................

................... 3-11

.......................................... 3-12

................................................. 4-3

3-9
3-10

4-2

4-4
4-8

List of Tables

SECTION 2

Table 2-l

SECTION 4

Table 4-1
Table 4-2
Table 4-3
Table 4-4
Table 4-5
Table 4-6
Table 4-7

- Getting Started

Fuse Replacement . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .

- GPIB Interface

Multiple-line Interface Message
InterfaceFunctions..
BusDriverSpecifications
Response to Interface Messages
StatusByte..
Model 3910 Main Parameter Setting Messages
TypicalExecutionTimes

............................................................

......................................................

....................................................

..............................................

...................................................

...............................................

....................................

2-2

4-5
4-6
4-6
4-7
4-9
4-10
4-12

SECTION 1

t General Information

1 .I INTRODUCTION

The Model 3910 Eunction Synthesizer can generate fre­quencies between O.lmHz and 1MHz. The Model 3910
can generate the entire band at a resolution of O.lmHz,
with a high-frequency accuracy of f30ppm.

Q 2/,squarelX,ris-

Five AC waveforms, sine
ing sawtooth/l, and falling sawtooth\ are available. A

maximum of tlOV DC can be added onto each output.
Maximum output voltage for all waveforms is 20V p-p/
no load or lOVp-p/5On load.

Since frequencies are synthesized directly by a custom
LSI digital IC, accuracy and stability are high, and the fre-

quencyswitching time is short. Another advantage is the
continuity of phase at frequency switchover.

In addition to continuous oscillation, burst oscillation,

trigger oscillation, and gate oscillation are available. The

Model 3910 also provides a continuous output of direct

current voltage. An external trigger input provides an ex­ternal trigger signal during trigger or gate oscillation. The
square-wave duty cycle is also variable.

The Model 3910 uses a single line, ll-character LED dis­play to display the values of oscillation frequency, pa-

, triangle

,

rameters, and other values. Settings are easily made us­ing push-button keys and rotary knobs.

A GPIB (IEEE-488) interface is available as an option for
the Model 3910. With the exception of the AMPTD, am­plitude setting; DC OFFSET, added quantity setting; and
DUTY VAR, duty ratio setting; a GPIB equipped Model
3910 can be programmed over the bus for the same oper­ating modes and parameters that can be controlled from
the front panel.

1.2 FEATURES

l Wide bandwidth: O.lmHz to 1MHz (resolution

O.lmHz).

0 &30 ppm frequency accuracy.

l Phase continuity, at frequency switchover.
l Five ACwaveformsavailable: %,2/,n,n,andl

l The duty cycle can be set to values between 10% and

90% for frequencies up to 1OOkHz.

l High output: 2OVp-p/no load, lOVp-p/50Qload.

0 Low distortion: 0.3% or less (1OHz to IOOkHz).

l DC output voltages

fiV/5OQ load.

l Burst oscillation mode: Repeats oscillation of wave

number specified by mark wave (l-16) and space wave
number (l-16).

o Trigger oscillation and gate oscillation:

Trigger source: External by front panel BNC plug or
push-button key.

available: flOV/no load,

l-l

SECTION 1

General Information

Start/stop phase: -360” to +360”.
Input voltage: ‘ITL level (pulls up 74HC14 input by

5.1K). Minimum pulse width ZOOnsec.
Trigger: Oscillates wave number specified by wave
number (l-16) by trigger signal.
Gate: Integral wave number oscillation by trigger
signal.

Waveform and frequency range:

Sine wave, square wave (duty fixed); O.lmHz to
IMHZ.
Triangle wave, square wave (duty variable), rising
sawtooth wave, falling sawtooth wave; O.lmHz to

lOOkHz, oscillation possible up to 1MHz.
Each parameter setting can be modified using the
MODIFY knob and the CURSOR keys. The single line,

11 character LED display, clearly displays all neces-

sary information; oscillation frequency, GPIB address

(when installed), start/stop phase, mark wave num­ber, and space wave number.
Battery backed-up memory stores the configuration in
effect when power is turned off.
Optional GPIB interface allows the Model 3910 to be
programmed over the GPIB (IEEE-488 interface bus).

1.3 WARRANTY INFORMATION

Warranty information is located on the inside front cover
of this operator’s manual. Should your Model 3910 re­quire warranty service, contact the Keithley representa­tive or authorized repair facility in your area for further
information. When returning the instrument for repair,
be sure to fill out and include the service form at the back
of this manual in order to provide the repair facility with
the necessary information.

The WARNING heading used in this manual explains
dangers that might result in personal injtuy or death. Al­ways read the associated information very carefully be­fore performing the indicated procedure.

The

CAUTION

hazards that could damage the instrument. Such damage
may invalidate the warranty.

heading used in this manual explains

1.6 UNPACKING AND REPACKING

1.6.1 Unpacking

After carefully unpacking the instrument from its ship­ping carton, inspect it for any obvious signs of physical
damage. Report any such damage to the shipping agent
immediately. Save the original packing carton for storage
or possible future shipment.

1.62

The following items are included with every Model 3910
order:

l

Model 3910 Function Synthesizer

0 Model 3910 Operator’s Manual

l

Power Cord

l

Fuse (lA, 25OV, 5.2 x 2Omm)

l

BNC to BNC signal cable

l

Additional accessories as ordered.

Shipment Contents

1.4 MANUAL ADDENDA

Any improvement or changes concerning the instrument
or manual will be explained in an addendum included
with the unit. Be sure to note these changes and incorpo­rate them into the manual before using the unit.

1.5 SAFETY TERMS AND SYMBOLS

The following safety terms and symbols are found on the
instrument or used in this manual.

A

The

user should refer to the operating instructions.

l-2

symbol on the instrument indicates that the

1.6.3 Operator’s Manual

If an additional manual is required, order the manual
package, Keithley part number 3910-900-00. The manual
package includes an operator’s manual and any perti­nent addenda.

1.6.4 Repacking For Shipment

Should it become necessary to return the Model 3910 for
repair, carefully pack the unit in its original packing car­ton or the equivalent. If the original carton is not available
or damaged, be sure to use a cardboard box of sufficient

strength and room. Pad the empty spaces in the carton
with adequate packing material to hold the unit firmly in
place.

General Information

SECTION 1

Include the following information:

l Advise to the warranty status of the instrument.
l Write ATTENTION REPAIR DEPARTMENT on the

shipping label.

o Fill out and include the service form located at the back

of this manual.

1.7 OPTIONAL ACCESSORIES

The following accessories are available for use with the
Model 3910.

Models 3900-l and 3900-2 Rack Mounting Kits: The

Model 3900-l mounts one Model 3910 in a standard

IPinch rack. The Model 3900-2 mounts two Model 3910s
side by side in a standard 19-inch rack. Both kits include
all necessary hardware for proper rack mounting of the
instruments.

Model 7007 Shielded IEEE-488 Cables:

7007-l (lm, 3.3ft.j and Model 7007-2 (2m, 6.6ft.j can be
used to interface the Model 3910 tothe IEEE-488 bus.

The Model

Model 7051-2 BNC-to-BNC Cable:

50R BNC to BNC cable (RG-58C) 2ft. (0.6m) in length.

The Model 7051-2 is terminated with male BNC connec-

tors on both ends.

Model 7051-5 BNC-to-BNC Cable:
5OQ

BNC to BNC cable (RG-58C) 5ft. (1.2m) in length.

The Model 7051-5 is terminated with male BNC connec-

tors on both ends.

Model 7051-10 BNC-to-BNC Cable:

is similar to the Models 7051-2 and 70516 except that it is

lOft..(2.4m) in length.

Model 7754-3 BNC-to-Alligator Cable:

7754-3 is a 3ft. (0.9m) 5Ofi cable (RGd8C), terminated
with a male BNC connector on one end and two alligator
clips on the other end.

Model 7755 5Oa Feed-Through Terminator:

7755 is a BNC to BNC adapter that is terminated with a
5OQ resistor. VSWR is ~1.1, DC to 25OMHz.

The Model 7051-2 is

The Model 7051-5 is

The Model 7051-10

The Model

The Model

Model 3911 IEEE-488 Interface:

tion a maximum of 15 Model 3910s can be connected on
the same bus, data line transfer uses a 3-line handshake
mefhod, enabling reliable data transfer between data
sending (talkers) and receivers (listeners) having differ­ing data transfer rates.

With the Model 3911 op-

1.8 SPECIFICATIONS

Detailed Model 3910 specifications may be found in Ap­pendix B.

l-3

SECTION 2

Gettina Started

2.1 INTRODUCTION

This sections contains basic information on installation,

power line connections, and it also provides typical sim­ple operating examples.

2.2 INSTALLATION

The following paragraphs discuss Model 3910 installa­tion. In particular, use adequate care when installing the
unit. Improper installation will adversely affect the life,
reliability, and safety of the unit.

The Model 3910 weighs about 7 lbs; be careful when car­rying the unit or mounting it in a rack.

2.2.1 installation Location

The allowable ambient temperature and humidity
ranges for the Model 3910 are.

Operating: 0 to 4O”C, 10 to 9O%RH
Storage: -10 to 5O”C, 10 to 8O%RH

Be sure to install the unit in a location that satisfies these
temperature and humidity conditions. Also the environ-

ment must be free of dust and vibration, and the Model
3910 must not be exposed to direct sunlight.

The Model 3910 uses a line filter, but pulse noise or strong
magnetic or electric fields may cause incorrect operation
of the unit. Do not install the unit near a source of pulse
noise or strong magnetic or electric fields.

The guard on the rear panel of the unit is designed to pro­tect rear panel connectors and should not be used as a leg
for installation. Do not stand the unit vertically on the
rear guard because it may fall over, causing instrument

damage or personal injury.

2.2.2

The Model 3910 is ‘air-cooled by vents. Insufficient air

flow may cause a component in the unit to fail. Follow the
instructions given below.

l

Cooling

CAUTION
Observe the following precautions to pre­vent damage to the unit:

A vent is provided on the bottom panel of the
unit. Install the unit on a rigid, flat surface,
and avoid installing it on soft material such
as a cushion. Be careful not to insert foreign

2-l

SECTION 2
Geffina Started

material between the bottom of the unit and
the surface underneath. Another vent is lo­cated on the top panel of the unit. Be careful
not to block the top vent by placing an object
on top of the unit.

l

Avoid mounting two or more units verti­cally. Placing one unit on top of another will
obstruct the vents.

2.3 LINE POWER SUPPLY

The Model 3910 operates with a lOOV, 12OV, 22OV, or

240.7 *lo%, 48 to 62Hk, single-phase AC power supply.
The power consumption is approximately 25VA.

2.3.1 LINE Voltage Selector Switch

The LINE voltage selector switch on the rear panel allows
you to change operating voltage of the power supply.

The standard setting of the switch is the same as the volt-

age available in the country to which the unit is shipped.

To change the power supply voltage, first disconnect the

line cord, and set the supply voltage switch in the correct
position. Wait at least five seconds before turning the
power back on after turning it off.

WARNING

The Model 3910 is equipped with a 3-wire
power cord that contains a separate ground
wire and is designed to be used with
grounded outlets. When proper connections
are made, instrument chassis is connected to
the power line ground. If the AC outlet is not

ounded, the rear panel ground terminal

=!= must be connected to safety earth

b

ground using #18AWG (or larger) wire be­fore use.

2.3.3

The line fuse, which is integral with the power line recep­tacle, protects the instrument from over-current situ­ations. To replace the fuse, first disconnect the line cord,
then pry out the fuse compartment (immediately to the
right of the FUSE marking) with a small screwdriver. A
spare fuse is located in the compartment with the fuse be­ing used. Replace the blown fuse only with the type listed
in Table 2-1, then replace the fuse holder.

Line Fuse

WARNING
To avoid a shock hazard, disconnect the line
cord from the instrument before replacing
the fuse.

CAUTION
Use only a fuse of the rating listed in Table
2-1, or instrument damage may occur.

WARNING
To avoid a shock hazard, disconnect the
power cord from the instrument before

changing the supply voltage setting.

CAUTION
Be sure to set the line voltage switch to the
correct position for the line power voltage to
be used. Operating the instrument on an in­correct voltage may cause damage to the unit.

2.3.2

Connect the supplied power cord to the rear panel Line
receptacle and to a grounded AC power receptacle sup­plying the correct voltage.

Line Receptacle Connection

2-2

Table 2-1, Fuse Replacement

Fuse Current Keithley

Line Voltage

lOOV, 120v 1A
220,240v

NOTE: Fuses are 5 x2Omm and have UOV, normal blow ratings.

Rating Part No.

FU-96-2

ID-4

FU-96-1

2.4 HANDLING PRECAUTIONS

When the front panel or case becomes

a soft

cloth. If the panel or case is too dirty for cleaning
with a dry cloth, dampen the cloth in mild detergent, and
wipe the panel or case with the damp cloth. Never use
solvents such as thinner or benzene, or chemical dust
cloths to avoid damaging the case or front panel surfaces.

dirty, clean it with

SECTION 2

Gettim?

Started

2.5 BASIC OPERATlON

The following paragraphs summarize front panel operat-

ing controls, give typical test connections, and discuss
typical operating examples for the Model 3910.

2.5.1 Front Panel Summary

Figure 2-l summarizes each front panel feature. For de-

tailed information on each operating feature, refer to Sec­tion 3.

2.5.2

Typical Test Connections

Figure 2-2 shows typical tests connections between the
Model 3910 main synthesizer and a DTJT. Note that 5OL2

characteristic impedance cables such as the Model 7051

should be used for output connections.

%I I11111

LED indicator when

Figure 2-1.

Front Panel Summary

Depressing CLEAR key
first, then either right or
left cursor key will reset
all digits to the right or
left of the cursor column
to 0. Dudng GPIB
operation+ depressing
this key will return
control to LOCAL

mxxn+inn

2-3

SECTION 2
Gettim Started

Model 3910

5052 BNC Coaxial cable

(Model 7051 or equivalent)

OUT

Figure 2-2.

Typical Connections

2.5.3 Operating Examples

The following examples give step-by-step instructions
for setting basic Model 3910 operating parameters. The
Model 3910 can be connected to an oscilloscope to view

the results of the various operating examples.

Example 1: Selecting the Waveform Type (Function)

The first sequence will adjust the Model 3910 to output a
sine wave, with a continuous sweep.

1. Press DISPLAY SELECT to indicate frequency
(lower LED).

2. Press FCTN to cycle through the five options until
the LED indicates a SINE wave (top LED).

3. Press MODE to indicate CONT (continuous sweep).

Example 2: Setting the Waveform Frequency or Period

This sequence will set the Model 3910 to a frequency of
5OOHz, without regard to any previous setup. You will
have to determine whether to use step 1 or 2 in this se­quence because there is no way to know what setup was
used for the previous test. Since the Model 3910 retains
only one setting in memory, that setting is always the last
one.

1. If the display shows a frequency higher than 500Hz,
use this next sequence. Otherwise skip to step 2.

A. Move the cursor to the seventh position: The sev-

enth position, 1OOHz column, will blink. Press
the CLEAR key and at the same time press the
left cursor key. All digits to the left of the blink­ing digit will return to 0 (erase).

B. The seventh position, 1OOHz column, will be

blinking. Rotate the MODIFY knob UP (clock­wise) to increase or DOWN (counter-clockwise)
to decrease the digit to the correct value, 5 in the
1OOHz column.

C. If any of the lower digits (less significant digits)

in the displayed number are above zero, press
the CLEAR key and at the same time press the

right cursor key. All digits to the right of the
blinking digit will return to 0. The display should
now show the following digits: 5000000
(5OO.OOOOHz).

2. If the display shows a frequency less than 5OOHz
(5000000), use this sequence:

A. Assume the display indicates a frequency of

86Hz. Press the left, or right, cursor as necessary
to make the column to the left of 8 blink. A u will
appear in this column.

B. Rotate the MODIFY knob UP (clockwise) and a

number will appear in the 1OOHz column. Adjust
this number to 5.

C. Press the CLEAR key and at the same time press

the right cursor key. All digits to the right of the
blinking digit will return to 0. The display should
now show the following digits: 5000000
(500.0000Hz).

2-4

SECTION 2

Getting Sfarted

NOTE

The frequency may be increased quickly, us­ing the above method, but no similar action is
available to rapidly reduce the frequency set­ting.

Example 3: Setting the Output Amplitude

This step sets the amplitude of the existing waveform to a
value of lOmVp-p:

Use the cursor down key to set the amplitude range so it
indicates O.O;?Vp-p (2OmVpp). RPotate the AMpTD knob
until the scope indicates lOmVp-p.

Example 4: Changing the Output to a Square Wave

This example changes the output to a square wave with
variable duty cycle, while maintaining the present fre­quency, in continuous mode.

1. Press FCTN twice to indicate a square wave output.
Note that the output waveform has equal time-on
and time-off.

2. Press DUTY VAR to allow variable duty cycle (LED
on). Rotate the associated knob below the key to cre-

ate square waves with different on- and off-times.
Leave the square wave in some extreme variable po­sition; that is, an obviously unequal on- or off-time.

3. Press DUTY VAR key again. The scope presentation
reverts to a square wave with equal on- and off­times.

4.

Press the DUTY VAR key again. The scope should
display the unequal duty cycle from the previous
step.

Example 5: Adjust the DC Offset

This step adjusts the DC offset value based on the center-

line (zero or average) voltage level of the existing
waveform.

1. Press the DC OF!ZSET key (LED on). Rotate the asso­ciated knob and note the vertical movement of CH A
on the scope. This movement corresponds directly

with the offset voltage applied by the rotation of the
knob. Leave the signal with a significant offset and
go to the next step.

2. Press DC OFFSET again (LED off). The scope presen-

tation reverts to the original value of zero offset.
Press the key again and the offset value re-appears
and the CH A display moves off zero. Press the key
once more to return the scope to zero offset (LED
off).

2-5

SECTION 3

Operation

3.1 INTRODUCTION

This section contains detailed information on front panel
operation of the Model 3910. For detailed GPIB (IEEE488
bus) operation, refer to Section 4.

3.2

3.2.1

The front panel of the Model 3910 is shown in Figure 3-1.
The front panel is made up of a LED display and a control
panel with various push-button switches and knobs. The

FRONT PANEL AND REAR PANEL
DESCRIPTION

Front Panel Description

LED display presents information useful for the opera­tion of the Model 3910, such as the value of each parame­ter and the range of permissible parameter values. Along
the bottom edge of the front panel are various input/out­put BNC connectors.

Most settings are maintained in battery backed-up mem­ory. As a result, the Model 3910 automatically assumes
the previous settings when the power is first turned on.

Each front panel feature is described below. The circled
number to the left of each description corresponds to the
appropriate number shown in Figure 3-1.

3-l

SECTION 3

Operation

Figure 3-1.

1

0

2

0

3

0

Model 3910 Front Panel

POWER ON/OFF (Power switch)
POWER controls AC power to the Model 3910.

Push this switch up to turn power on, and push
down to turn power off.

Display
The single-line 1 l-character display shows oscil-

lation frequency, parameter values, and other
important information during operation. An ac­tive display also indicates that instrument power
is turned on.

DISPLAY SELECT
Push-button key that selects the parameter dis-

played to either oscillation frequency or GPJB
address (only when GPIB option is installed),

start/stop phase, mark wave number, and space

4

0

wave number. When LED at the lower left of the
display is lit oscillation frequency is selected.
When LED at the upper left of the display is lit
GPIJ3 address, start/stop phase, and mark and
space wave numbers are selected.

DUTY VAR FXD, VAR (Square wave dufy
q&9

,Push-button key to select either variable duty or

fixed square wave output. When LED in center
of key is lit variable duty is selected.

111,111, r&VarlabZe duty ratio adjustment)

Rotating the variable duty adjustment knob al­lows you to program the square wave duty cycle.
The allowed duty cycle ranges from 5% to 95%
under lOkHz, and from 10% to 90% at 1OkHz to
1oOkHz. In the variable duty mode, the upper
frequency limit for square waves is restricted to
1ookHz.

3-2

SECTION3

Operation

6

0

7

0

8

0

9

0

IO

0

11

0

12

0

13

0

+I- (DC offset value adjustment)
Rotating the DC offset value adjustment knob

sets the programmed offset voltage. The allow­able DC offset to be added to a waveform is be­tween -lOV and +lOV.

DC OFFSET ON, OFF

Push-button key to select whether or not DC off­set is added to the waveform. When LED in cen­ter of the key is lit offset is selected.Use the +/­offset value adjustment knob to add the deter­mined amount of offset to the waveform.

AMPTD

LEDs light to display the selected amplitude
range. The allowed amplitude range is from
2mVp-p to 2OVp-p. The values for the amplitude
setting are for no-load (open) output condi­tions.When the output is terminated with a 500
terminal resistor, amplitude range is one half of
the selected range.

V(Amplitude range down key)
When the down cursor key is pressed the maxi-

mum value of the amplitude output signal is re-

duced.

A (Amplitude range up key)
When the up cursor key is pressed the maximum

value of the amplitude output signal is in­creased.

FCTN

This key allows you to choose the
waveform. Available waveforms include :
(sine wave), 2/ (triangular wave), 111 (square

wave), V(ascending sawtooth wave), 1 (de­scending sawtooth wave).

The selected waveform is displayed in the func­tion LEDs.

FCTN

Refer to the lit LED to see which wave function
has been selected.

REMOTE

This lamp indicates the remote state when the
GPIB option is installed and listener is specified
from the controller.

(Amplitrrde range display)

(Function:

(Displays the selected function)

(Remote state display)

waveform)

out ut

4J

14

0

15

0

16

0

17

0

18

0

19

0

20

0

21

0

MODE

This key allows you to choose the oscillation

mode. Available modes include: CONT (con­tinuous oscillation), BURST (burst oscillation),

TRIG (trigger oscillation), GATE (gate oscilla-

tion). In addition, it is also possible to select DC

for a continuous output of direct current voltage.

MODE

Refer to the lit LED to see which mode has been
selected.

MAN Manual trigger key)
This key allows the operator to manually gener-

ate a trigger input pulse during trigger or gate
mode of oscillation.

TRIG IN

This BNC connector is an input for external TTL­level signals, which can be used to trigger the
Model 3910 in TRIG (trigger) and GATE modes
of operation. When this input goes from high
level to low level, it operates as a trigger signal.

SYNC OUT (Synchronous output)
This BNC jack provides a TIL-level signal at the

same frequency as the FCTN OUT output
waveform.

AMPTD MIN,

Turning this knob allows you to set the output
amplitude of the unit when the FCTN OUT key
has been activated. The allowed amplitude
ranges from 2mVp-p to 2OVp-p.

FCTN OUT

FCTN OUT turns the output waveform off or on
to the BNC plug of FCTN OUT. When the output
is off, the main output signal is turned off and
open-circuited. This can be shorted to ground by
switching an internal short plug. The current
status of this key can be determined by the LED
in the center of the key. If lit, FCTN OUT is on.

FCTN OUT

oufpft)

This BNC jack provides the waveform output
signal. The maximum output voltage range is
SOVp-p/open circuit, and the output imped­ance is 50&J.

(Oscillation mode)

(Displays the selected mode)

(Tuigger input)

MAX (Amplitude adjustment)

ON, OFF (Signal output ON/OFF)

(Function output:

waveform

3-3

SECTION 3
Operation

22 4(Left Cursor)

0

This key moves the cursor one column to the left
each time it is pressed. If held continuously for
more than 0.3 seconds, the cursor will continue
moving to the left.

CLEAR (Local)

If this key is pushed first and then either the right
or left cursor key is pushed at the same time, all
digits to the right or left of this column will be re­set to 0. In Gl?lB remote mode, this key is a return
to local control key.

24

0

MODIFY UP, DOWN (Modify knob)

This knob is used to increase or decrease the set
value of the display. Turning the knob clockwise
increases the value while turning the knob
counter-clockwise decreases the value. This

knob can be used to set the following parame-

ters: frequency, Gl?lB address (O-301, start/stop
phase (f360.0’), mark wave number (l-16), and
space wave number (1-16).

25 b(Righ t Cursor)

0

This key moves the cursor one column to the
right each time it is pressed. If held continuously
for more than 0.3 seconds,the cursor will con­tinue moving to the right.

3.2.2

The rear panel of the Model 3910 is shown in Figure 3-2.
Each rear panel feature is described below. The circled
number to the left of each description corresponds to the

appropriate number shown in Figure 3-2.

Rear Panel Description

Figure 3-2.

3-4

Model

3920 Rear

Panel

SECTTON 3

Operation

26

0

27

0

GPIB

(General Purpose Interface Bus (option))

This connector is the 24-pin connector used to
connect the Model 3911 option of the Model 3910
to the GPIB (IEEE488 bus). Shielded GPIB ca­bles, such as the Model 7007, are recommended
for bus connectionsThe GPIB address is set by
first selecting the GPlB display. Rotate the MOD­IFY knob UP (clockwise) to increase or DOWN
(counter-clockwise) to decrease the GPIB ad­dress.

LINE Voltage Selector

This switch sets the Model 3910 for the correct
line voltage. Using a flat-blade screwdriver, set

the switch in the proper position for the supply

voltage in your area.

WARNING

To avoid a shock hazard, disconnect the line

cord before changing the switch position.

CAUTION
Operating the Model 3910 on an incorrect
line voltage may result in instrument dam­age.

(Supply voltage switch)

3.3 INPUT AND OUTPUT CONNECTIONS

3.3.1

One signal can be applied to the BNC connector of the
Model 3910. The specification of that input signal is given
below.

Logic Input

The logic input is TRIG IN (external trigger input).
Input name: TRIG IN (External trigger

Input voltage: TTL level
Allowable input voltage:
circuit: See Figure 3-3, Logic Input

Input Connection

CAUTION
Be careful no to exceed the maximum allow­able input voltages, or instrument damage
may occur.

input) external trigger dur­ing TRIG, GATE operation

ov to +5.5v
circuit

28

0

@Q

LINE

(Power Input Connector)

The LINE connector is used to connect the in­strument to AC power.

WARNING
To avoid the possibility of electric shock,
connect the Model 3910 to grounded AC out­let using the supplied 3-wire power cord or
the equivalent.

(Grounding Terminal)

The grounding terminal is connected to the chas-

sis of the Model 3910. To prevent interference
and for safety, be sure to ground this terminals

WARNING

If the Model 3910 is connected to an un­grounded AC outlet, connect the grounding
terminal to safety earth ground using
#18AWG minimum wire before use to avoid
the possibility of electric shock.

V V

1 Figure 3-3.

Figure 3-3. Logic Input Circuit

3.3.2

3.3.2

Two output signals are available from the BNC connec-

tors of the Model 3910. The specifications of the output

signals are given below.

Be careful not to connect an external signal to
an output connector, or instrument damage
may occur.

Logic

Input

Circuit

Output Connections

Output Connections

CAUTION

3-5

SECTION 3

Analog Output

The analog output is FCTN OUT (main waveform out-

put)

Output n&e: FCTN OUT (Main

Waveform Output)

Maximum output voltage:
Output impedance:

Recommended Impedance: 50!2
Short circuit ljrotection See Figure 3-4, Output Cir­circuit: cuit

ZOVp-p/open,
lOVp-p/son

5on 32%

Analog Output Considerations

The FCTN OUT (main waveform output) impedance is
50!2. To maintain maximum amplitude across the entire
bandwidth, and for maximum square-wave quality, use
a 5OQ cable for connections, and terminate the opposite
end of the cable with a 5OQ impedance. Note that the
Model 3910 displays voltage amplitude for open circuit
conditions. The actual output voltage with a 5OQ termi­nation is about half that for no-load conditions.

Logic Output Considerations

The SYNC OTJT (synchronous output) is driven by a
74LS type logic IC. The maximum load is about 25ksz. Be
careful not to connect a load that exceeds the drive capa-

bility of this type of TTL IC. Also, do not use excessively

long connecting cables, as the resulting capacitance may
have detrimental effects on the output signals.

The SYNC OUT impedance is matched at 5OQ at higher

frequencies. Relatively good waveforms will be obtained

if 5OQ coaxial cables are used; however, cables connected

to this output must not be terminated with a 5OQ imped­ance.

3.4 STARTUP

1. Check that the supply voltage switch is set at the
proper position for the supply voltage. The allow­able supply voltage range is +lO% of the voltage at
which the supply voltage is set.

CAUTION
Operating the Model 3910 in an incorrect
line voltage may result in damage to the unit.

Logic Output

The logic output is SYNC OTJT (synchronous output).

Output name:
Output voltage:
circuit:

SYNC OUT
TTL level
See Figure 3-4, Output Cir­cuit

Figure 3-4. Output Circuit

2. Make sure that the power is off, then plug the sup­plied power cable firmly into the LINE connector on
the rear panel of the Model 3910. Insert the plug into
a grounded AC power receptacle.

WARNING
To avoid the possibility of electric shock, use
only grounded AC receptacles for power
connections.

Turn on Model 3910 power by pushing the front
panel POWER switch. The power is on when the
POWER switch button is up; power is off when the
POWER switch is down. When the power is on, the
Model 3910 will begin normal operation, and the
LED display will be on.

3. When the power is first turned on, the Model 3910
will return to the previous settings effective prior to
power-off, and the unit will display the main pa­rameters.

If the previous settings were not stored correctly, the
error code “ERR3” will be displayed. In this case, if
the CLEAR key is pushed, the machine goes to the
initial reset state and can be used normally, but the

3-6

SECTION 3

Operation

settings prior to turning off the power are lost. This
situation occurs when the backup battery used to
maintain memory is drained and the stored data can­not be maintained or if the power is cut off while the
machine is being set. Fully charged batteries can re­tain memory for approximately 30 days. This time
period, however, varies slightly with ambient tem­perature and from one battery to another.

The backup batteries may be discharged when the
Model 3910 is used for the first time after being pur­chased. If “ERR 3” is displayed during initial opera­tion, replace the batteries using the information pro­vided in the service manual.
The FCTN OUT ON/OFF (function output) state is
not saved. The FCTN OUT ON/OFF setting de­pends on the setting of the internal short plug. The
factory default setting at power-on is function out­put on. Consult the service manual for details on set­ting the internal short plug.
If, at power on, the Model 3910 does not enter the
mode with settings that were effective immediately
before previous power-off (or the preset operating
modes), or if the main display does not appear, con­tact your Keithley representative or the factory to de­termine the correct course of action.

ERR2 (RAM error)

l Abnormality in internal RAM of the machine.

ERR3 (Memory backup error)

l Battery backup operation failure.

When “ERRl” and “ERR2” occur, try to turn the power

on again several times. If the error is still displayed, it is
probably a breakdown. Contact your Keithley represen­tative or the factory to determine the correct courseof ac­tion.

When “ERR3” is displayed, replace the batteries inside
with new ones. Refer to the service manual for replace­ment information.

If the CLEAR key is pressed when “ERR3” is displayed,
the machine will be set to its default settings, and will
then go into the operating state, where it can be used nor­mally. However, the settings prior to turning off the
power will be erased.

NOTES:

1. Wait at least five seconds before turning on the
Model 3910 after turning it off or it may not operate
normally.

2. For precise measurement applications, allow the
Model 3910 to warm up for at least 30 minutes to al­low internal circuits to stabilize.

3.5 OPERATING PROCEDURES

3.51 Error Codes

When an error occurs, the Model 3910 displays an error
code on the left side of the numerical display.

Displayed error codes and their meanings are summa­rized below.

ERR1 (ROM error)

l Abnormality in internal ROM of the machine.

3.5.2

Frequency Setting

The frequency setting is used to set the cycles per second
of the waveform selected. To change the frequency set­ting, first ensure that the frequency display has been se­lected. To select the frequency display, depress the DIS­PLAY SELECT button so that the LED indicator is lit next
to MHz on the lower left of the display.

Once this action has been performed the Model 3910 can
now have the frequency set. To move the cursor to the po­sition you wish to change, just use the4 key or the, key.
To change the frequency setting, turn the MODIFY knob
UP (clockwise) to increase the setting or DOWN
(counter-clockwise) to decrease the setting.

The allowed frequency range for the sine and square
waves (with 50% duty cycle) is from O.lmHz to IMHz; for
other waveforms, the upper limit is 1OOkHz for good
quality waveforms. Although waveform quality will be
of reduced quality, oscillations up to 1MHz can be set for

triangle (2/ >,

rising sawtooth (v >, falling sawtooth

(u ), and variable duty square wave (m >.

SECTION 3

Operation

3.5.3

The amplitude setting establishes the output voltage

from the FCTN OUT BNC jack. The amplitude range dis­play will display only the maximum possible output
value in the current setting.

To accurately set the output amplitude, first set the de-

sired range using the amplitude range keys. Then rotate
the AMPTD knob to fine tune the output. The output
value can be measured at the FCTN OUT BNC jack with a
voltmeter or by using an oscilloscope. However, take
note of the frequency characteristics of the voltmeter.

Amplitude setting can be performed by using both the
AMPTD knob and the amplitude range keys. The al­lowed amplitude range is 2mVp-p to 2OVp-p.

When the DC offset is OV, the allowed amplitude range is

2mVp-p to 2OVp-p. If, however, the DC offset is not OV,
the sum of the AC amplitude setting/2 and the DC offset
must not exceed the AC amplitude setting.

Output Amplitude

Using DC
the value that appears at the output jack. Valid offset val­ues are within the range of +lOV to -lOV.

For all AC waveforms, the DC offset is added to the aver-

age

waveform. When adding DC offset to the output
waveform, set them so that the sum does not exceed that
of your AMPTD (amplitude range display). To prevent
errors from oc
offset combinations, first set the offset to OV, change the
AMPTD setting, then set the offset to the desired value.
Settings that exceed the range of the AMM’D are possi­ble, but the waveform will be distorted or clipped. Check
the waveform with an oscilloscope.

3.5.5

as

a mode, the offset voltage is the voltage of

value of the peak-to-peak amplitude of the AC

curring while programming amplitude-

Waveform Selection, Square-Wave

Duty Cycle, and Synchronous Out-

put

Waveform Selection

Pressing the FCTN key advances the present waveform
function on the upper right of the front panel. Available

waveforms include: sine ( s ),tiangle ( 2/ >, s uare

6u ), rising sawtooth (A ), and falling sawtooth ( \ 1.

The variable range of the AMPTD knob is 20dB.

The AMl?TD knob can be used only on AC waveforms;

use the DC OFFSET knob to set the DC output voltage of
the DC waveform. When the DC waveform is selected,

you can still set the amplitude range by using the ampli-

tude range keys.

3.5.4 DC Offset

Pressing the DC OFFSET key selects whether or not DC

offset is added to the waveform. When the LED in the

center of the key is lit the DC offset is active. The current
DC offset setting cannot be observed from the Model
3910 display. The DC offset setting should be made using
a voltmeter or an oscilloscope.

To modify the DC offset, rotate the +/- offset value ad­justment knob directly below the DC OFFSET key clock­wise to increase the setting and counter-clockwise to de­crease the setting.

For all AC waveforms, the p-p value of the amplitude
will remain unchanged when you change the waveform.

Square-Wave Duty Cycle

The duty cycle is the ratio of the time period of the
waveform high-level duration to the time period of one
complete cycle of the waveform expressed as a percent­age. For example, assume a 1OkHz square wave has a
time period of 100psec. If the high portion of the
waveform has a period of 30pec, the duty cycle is
30/100x100=30%.

Two square-waveform duty cycles are available: one
with the duty cycle fixed at 50% and the second mode
with a variable duty cycle. The duty cycle applies only to
the square-wave function. When the Model 3910 is in the
variable duty-cycle mode, the upper frequency limit is

1OOkHz and the maximum jitter is 15011s.

To change the duty cycle, press the DUTY VAR FXD,
VAR key. If the LED is lit in the center of the key the vari-

3-8

SECTION 3

Operafion

able duty
duty cycle, turn the (variable duty) knob directly below
the DUTY VAR key. The variable range of duty ratio is
between 5% and 95% for frequencies up to 1OkHz. For
frequencies up to 100 kHz, the variable range is between
10% and 90%. It can actually be set until the point where
the waveform is extinguished, but the waveform may be­come unstable. To select the fixed 50% duty cycle mode,
press the DUTY VAR FXD,VAR key so that the LED in
the center of the key is no longer lit.

Note that the duty cycle setting also changes the duty cy­cle of the sync out signal.

To extend the duty cycle range, use the trigger oscillation
mode and one square waveform cycle. Refer to para­graph 3.5.6 for details on setting the oscillation mode.

Synchronous Output

Figure 3-5 illustrates the phase relationships between the
FCTN OUT waveform and SYNC OUT (synchronous
output). Note that as the frequency increases, a substan-

range

has been selected. To modify the variable

tial phase differential will result between the waveform
output and the synchronous output signals.

3.5.6 Oscillation Mode

Oscillation Mode Selection

The oscillation mode setting is selected by the MODE

switch on the right side of the front panel. The present os­cillation mode is displayed by the lit LED next to the se­lected mode. Each time the mode key is depressed the
mode is advanced by one. Available oscillation modes in­clude CONT (continuous), BURST, TRIG (trigger), and
GATE. In addition, it is also possible to select DC for a
continuous output of direct current voltage.

CONT (continuous mode)

When the continuous mode is selected, the instrument
generates the selected waveform continuously. Trigger­ing is not required, and the selected burst cycle and inter­nal rate
waveform:

parameters

have no effect on the output

-

Sine wave

Rising sawtooth wave

Waveform

Triangular wave

Falling sawtooth wave

Figure 3-S. Phase Relationship between FCTN OUT Waveform and SYNC OUT

Square wave

Duty variable square wave

3-9

SECTION 3

Operation

BURST

In the burst mode, the instrument generates the selected

waveform for the specified mark wave number and

space wave number. No trigger signal is required to initi-

ate the waveforms. The mark wave number and space

wave number can be set by first pressing the DISPLAY

SELECT button so that the LED is lit next to GPIB on the

upper left of the display. When the LED is lit next to

GPIB, the mark wave number and space wave number

can be found on the right side of the display. Then by us-

ing the 4 and b keys advance the cursor to either mark

wave number or space wave number. Turn the MODIFY

knob UP (clockwise) to increase the wave number or

DOWN (counter-clockwise) to decrease the wave num-

ber. The phase where oscillation starts can be set in 0.1”

from +360.0” to -360.0”.

TRIG (trigger)

In the trigger mode, the instrument generates the se-

lected waveform for the number of specified mark wave

numbers each time a trigger comes from the outside. The

trigger signal is effective only while oscillation is

stopped, and trigger signals prior to when the oscillation

finishes are ignored. To set the mark wave number first

press the DISPLAY SELECT button so that the LED is lit

next to Gl?lE on the upper left of the display. When the

LED is lit next to GPIB, the mark wave number can be

found on the right side of the display. Then use the4 and
b keys to advance the cursor to the mark wave number.

Turn the MODIFY knob UP (clockwise) to increase the

mark wave number or DOWN (counter-clockwise) to de-

crease the mark wave number. The phase where oscilla­tion starts can be set in 0.1” units from +360.0” to -360.0”.

Triggering is performed by either using the TRIG IN (ex­ternal trigger) BNC jack or by pressing the MAN (man­ual) key on the front of the unit.

Figure 3-6 shows the relationship between the trigger
signal and oscillation in TRIG mode.

GATE
In the GATE mode, the unit generates oscillations as long

as the gate signal (trigger signal) is on. When the gate sig­nal turns oW, the Model 3910 will always stop oscillating
at the end of one complete cycle even if the gate signal
turns off at the mid point of a cycle. Thus, the Model 3910
always provides integral cycles of oscillation. The phase
where the oscillation starts can be set in 0.1” units from
+360.0” to -360.0”.

Triggering is performed by either using the TRIG IN (ex­ternal trigger) BNC jack or by pressing the MAN (man­ual) key on the front of the unit.

Figure 3-7 demonstrates how the output waveform al­ways completes the current cycle when the gate signal
turns off.

Ignored

Figure 3-6. Relationship between Trigger Signal and OsciZlation in TRIG Mode

3-10

SECTION 3

Ozleration

Figure 3-7.

In the trigger or gate oscillation modes, if the
next trigger is applied at about the same time
the unit terminates oscillation, oscillation may
become unstable. In this situation, temporar­ily change the oscillation mode, then return
the unit to the original mode. Oscillation will
return to normal.

Relationship between Trigger Signal and Oscillation in GATE Mode

NOTE

DC Mode

DC is a mode in which oscillation from the synthesizer is
stopped. In this mode only a constant voltage is output.
When the MODE is set to DC, DC OFFSET ON/OFF
must be on (LED lit in center of DC OFFSET ON/OFF
key). To alter the output voltage, turn the +/- knob, di­rectly below the DC OFFSET ON/OFF switch, clockwise
to increase the voltage or counter-clockwise to decrease
the voltage. The maximum voltage of the DC output is

HOV, and current is up to lOOmA. Short circuit protection

on the output has been installed.

play. When the LED is lit next to GPIB, the start/stop

phase setting can be found in the center of the display. To

change the current start/stop phase setting, move the

cursor to the start/stop phase by using the4 and, cursor
keys. Then set the start/stop phase by turning the
MODIFY knob UP (clockwise) to increase the setting or
DOWN (counter-clockwise) to decrease the setting. The

allowed range for the start/stop phase parameter is

-360.0” to +360.0” with 0.1” resolution.

The definitions of each waveform and its phase are
shown in Figure 3-8.

The Model3910 generates square waves with a fixed 50%
duty cycle by processing sine waves with a zero-crossing
comparator that has hysteresis.The level of the generated
square wave, therefore, alternates high and low at ap­proximately 0”, +X30’, and &360” (within about ti.3’) de­pending on the past value of the phase. Thus, to set the
square-wave start/stop level high, set the phase to 90”.
Similarly, the phase should be set to -90” to set the
square-wave start/stop level low.

3.5.7 Trigger Parameters

Start/Stop Phase

The start/stop phase setting is the starting and finishing
position for waveform cycles. To set start/stop phase
press the DISPLAY SELECT button so that the LED indi-

cator light is lit next to GMB in the upper left of the dis-

The Model 3910 also generates the synchronous output
for the sine, triangle, and sawtooth waves by passing
each waveform through a zero-crossing comparator that
has hysteresis. As a result, the synchronous output level
changes at the same points as the square wave when the
phase is approximately 0”, +180’, or &360” for the sine or
triangle waves, or about +180” with the sawtooth wave.

3-11

SECTION 3
Oaeration

Center of
waveform
amplitude

Phase O”

Duty ratio fixed square wave

Center of

00

Rising Sawtooth Wave

0 Not including this point

l

Including this point

Center of
waveform
amplitude

I
I I
I I

1800 36il”

Phase O”

Duty ratio variable square wave

Center of
waveform

amDlitude

, I

0" 180" 360”

180” 360”

Phase

Falling Sawtooth Wave

Center of
waveform
amplitude

180” 360”

o Not including this point

l

Including this point

0 Not including this point

Figure 3-8. Definition

3-12

of

Phase

180” 360”

of

each Waveform

Phase

0” 180” 360”

.

SECTION 3

Otlerution

Mark Wave Number Setting
The mark wave setting is used to set the number of oscil-

lation cycles the unit generates each time it is triggered in
the BTJRST and TRIG oscillation modes. To set the mark
wave number, press the DISPLAY SELECT button so that
the LED is lit next to GPIB on the upper left of the display.
When the LED is lit next to GPIB, the mark wave number
setting can be found on the right side of the display. To
change the current mark wave number setting, move the
cursor using the 4 and @ cursor keys to the desired num­ber. Then turn the MODIFY knob Ul? (clockwise) to in­crease the setting or DOWN (counter-clockwise) to de­crease the setting. The allowable range for the mark wave
number setting is 1 to 16.

Space Wave Number Setting

The space wave setting is used to set the number of non-

oscillation cycles between each group of oscillation cycles
in the BURST mode. To set the desired space wave num-

ber, press the DISPLAY SELECT button so that the LED is

lit next to GPIB on the upper left of the display. When the
LED is lit next to GPIB, the space wave number can be
found on the far right side of the display. To change the
currents
ing the
turn the MODIFY knob UP (clockwise) to increase the
setting or DOWN (counter-clockwise) to decrease the
setting. The allowable range for the space wave number
is 1 to 16.

ace wave number setting, move the cursor us-

P

and b cursor keys to the desired number. Then

3-13

SECTION 4

GPIB Interface

4.1 INTRODUCTllON

4.1 .I GPIB Overview

The GPIB interface is a general-purpose interface bus sys-

tem recognized by the IEEE (Institute of Electrical and

Electronics Engineers) in 1975 and is a method of stan-

dardizing data transfer between measuring instruments

and peripherals. By building each controller and periph-

eral device into an interface conforming to this standard,
it is possible to establish complete hardware compatibil-

ity among devices.

UP to 15 devices may be connected to a single interface
b&, and data transfer is performed by threghandshake
lines, enabling reliable data transfer between data send­ers (talkers) and receivers (listeners) having differing
data transfer rates.

4.1.2 Major GPIB Specifications

Overall cable length: 20m maximum
Cable lengths between devices: 4m maximum
Number of devices connectable

(including a controller): 15 maximum

Transfer method: 3-line handshake
Transfer rate: 1M bytes/set (maximum>

Data transfer: g-bit parallel
Signal lines:

Data Bus: 8 Lines
Control bus: 8 Lines
(including DAV, NRFD, and NDAC handshake lines

and ATN, REN, IFC, SRQ, and EOI control lines)
Signal/system grounds: 8 lines
Signal logic: Negative

True (low-level): 0.8V maximum

False (high-level): 2.OV minimum

4.1.3 Bus Line Signals and Operation

The GPIB bus consists of 24 lines, including eight data
lines, eight control lines, and eight signal/system ground
lines.

Data Bus (DIOl to DI08)

DIOl through DIO8 are data input/output lines, which
are used to transfer both address and command informa­tion (the type of data present on these lines is determined

by the ATN line). DIOl is the least significant bit (LSB).

4-l

SECTION 4

GPIB Interface

Handshake Bus (DAV, NRFD, NDAC)

These three lines are handshake lines used to ensure reli­able data transfer.

DAV @&a Yalid)
This line indicates that the data on the DIO lines sent

from a talker or the controller are valid.

NRFD &Jot &eady Zoraata)
This line indicates when the listeners are ready to accept

data over the data lines.

NDAC Uot Data Kcepted)
This line indicates the acceptance of data by listeners.

EOI and Qr Jdentify)
This line is used to indicate the end of a multiple-byte

transfer sequence or, in conjunction with ATN, to execute
a parallel poll operation.

4.1.4

GPIB handshaking is performed by checking the status of
all listeners and inhibiting the next data transfer until all
listeners have completed the reception of data, so that the
slowest device on the bus can perform data transfer reli­ably. The handshaking operations are executed by the
following handshake line logic levels:

NRFD=High level: Alllisteners are ready for accepting
data.

DAV=Low level: A talker has valid data on the data bus.
NDAC=High level: All listeners have completed data re-

ception.

GPIB Handshaking

Control Bus (ATN, REN, IFC, SRQ, EOII

ATN UeNtion)
This line is an output line from the controller, and it indi-

cates whether the information on the data bus is to be in­terpreted as data or commands.

REN @emote ENable)
This output line from the controller switches devices be-

tween remote control and local control.

IFC (Inter]Eace Q.lear)
This output line from the controller clears the interface of

active talkers and listeners.

SRQ @en&e &eQuest)

DlOl
0102
D103
D104

EOI

DAV
NRFD
NDAC

IFC

SRQ

ATN

SHIELD

. Cable

Receptacle Side

/

D105
D106

D107
D108
REN
DAV GROUND
NRFD GROUND
NDAC GROUND
IFC GROUND

SRQ GROUND
ATN GROUND
LOGIC GROUND

This control line is used by a device to request service
from the controller. The controller detects this signal and
usually executes a serial or parallel poll operation.

4-2

IEEE-488

1

Figure 4-l. Interface Connector

SECTION 4

GPIB Inferface

NRFD

(Listener) --I,

DAV I I

(Talker)

NDAC

(Listener)

Data Bus

Signal

Valid Data

I 1

- Data bus disabled

Ready for next data byte.

Data bus enabled

Termination of
data reception

Data not received
(during data reception)

Figure 4-2. Handshake Timing Diagram

The handshaking timing diagram is in Figure 4-2. The
various timing points indicate the following:

4.1.5

Figure 4-3 shows a data transfer example using the three­line handshake process. In this example, the character
string “ABC” is sent, followed by the <CR> <LF> delim­iter.

4.1.6

l Only one talker may exist on the GPIB at a time.
l Data is sent to the listeners when the controller ATN

line is high (false).

l Source handshaking is performed automatically.
l A service request (SRQ) is sent to the controller by

other devices.

l The talker function is available with both the local and

remote modes.

l The talker function is canceled by any of the following:

When the talk address of another device is received.
When the device is addressed as a listener.

When the untalk (UNT) command is received.

When the interface clear (IFC) command is received.

Data Transfer Example

Basic Talker Functions

1

0

2

0

3

0

4

0

5

0

6

0

7

0

8

0

Indicates that all listeners are waiting for data.

The talker places the data byte to be sent on the
data lines. Output may have already occurred.

The talker checks NRFD, and, if high, DAV is set
low to indicate to the listener that the data is
valid.

When DAV goes low, the listener reads data, and
NRFD is set low, indicating to the talker that data
processing is in progress. Each listener sets
NDAC high at the completion of data input. The
NDAC logic level is the result of ORing the
NDAC signals from each listener.

When all listeners have completed receiving
data, NDAC goes high, indicating to the talker
that data reception has been completed.

The talker sets DAV high, indicating to the lis-

tener that data on the bus is no longer valid.

The listener checks to see whether DAV is high

and sets NDAC low, completing the handshake.
Indicates that all listeners have completed data

input, and the bus is ready to transfer the next
data byte.

4.1.7 Basic Listener Functions

l Two or more listeners may exist on the GPIB at any

time.

l Data is received from a talker when the controller

ATN signal is high.

l The acceptor handshake is performed automatically.
l The listener function is canceled by any of the follow-

ing:
When the device is addressed to talk.
When the unlisten (UNL) command is received.
When the IFC command is received.

4.1.8 Basic Controller Functions

l Only one controller can be active on the GPIB.
l The controller sets the ATN signal to low to address

devices to listen and talk, and to transmit commands
such as DCL.

0 The controller sends single-line commands such as

IFC and REN.

4.1.9 Multi-line Interface Messages

A multi-line interface message is sent over the data lines
with ATN set low. Table 4-1 summarizes these messages.

4-3

SECTION 4
GPIB Interface

DATA

ATN

DAV

NRFD

NDAC L

EOI

UNL Address

Talker

Listener

Address A 0

C CR

LF

Figure 4-3.

Data Transfer Example

4-4

1

I

LISTENER ADDRESSES
ASSIGNED TO DEVICES

LISTENER ADDRESSES

ASSIGNED TO DEVICES

TALKERADDRESSES

ASSIGNED TO DEVICES

I I

I I

MEANING DEFINED BY PCG

I I

SECTION 4
GPII?

Interface

4.2 OVERVIEW OF MODEL 3910 GPIB
INTERFACE

4.2.1 Introduction

The Model3910 GPIB interface has a wide variety of in­terfacing functions. These functions allow remote setting
of most of the parameters which can be set from the front
panel. Items that cannot be controlled from GPIB are
AMPTD, amplitude setting; DC offset, added quantity
setting; and DUTY VAR, duty ratio setting; which corre­spond to regulators other than the MODIFY dial on the
panel. The interface can also transfer setting data and
conditions to an external device, enabling the user to eas­ily configure a sophisticated automatic measurement
system.

Setting data and conditions are sent to the controller as
character strings in ASCII format.

4.2.2

Interface Functions
Table 4-2 shows the interface functions of the Model

3910.

Specifications

Bus Driver

Table 4-3 gives the bus driver specifications.

Table 4-3. Bus Driver Specifications

DIOl to D108

NDAC, NRFD, SRQ

I

DAV

EOI

Codes

Codes which can be received by the Model 3910 in lis­tener mode are in 7-bit ASCII format (bit 7 is ignored).
Codes can be sent using either lower-case or upper-case
letters. In either case, codes are interpreted and executed
identically. The space @OH), tab (09H), and semicolon

“;“(3BH) characters are ignored.

Talker (inquiry) mode transmission codes are also in ‘/bit
ASCII format. All letter characters are sent as upper-case
letters.

Open Collector

I

Three-state
Three-state

I

Table 4-2. Interface Functions

Function
Source Handshake SHl

Acceptor Handshake AH1
Talker T6

Listener

Service Request SRl

Remote/Local

Parallel Poll

Device Clear
Device Trigger DTO

Controller co

Subset Explanation

IA
RLl

PPO

DC1

Sending handshake all functions
Receiving handshake all functions
Basic talker, serial poll, talker cancel by MLA
Basic listener function, listener cancel by MLA
Service request all functions
Remote local all functions
No parallel poll functions
Device clear all functions
No device trigger functions
No controller functions

4-6

GPIB Primary Address Program Codes

SECTTON 4

GPIB Interface

The GPIB address of the Model 3910 is set as follows:

On the front panel press the DISPLAY SELECT button so
that the red indicator light is on next to GPIB on the upper
left of the display. Then move the cursor by using the cur­sor arrow keys so that the cursor is now in the GPIB dis­play. Set the GPIB address by rotating the MODEM knob
UP (clockwise) to increase the value and DOWN
(counter-clockwise) to decrease the value. Set values are
stored in battery backed-up memory when the power is
turned off.

Delimiter

The Model 3910 recognizes <CR>, <LF>, or <EOI> in any

combination as a delimiter for receiving code strings in
the listener mode.

The delimiter used when sending a response in the talker
mode is set from the front panel with the GPIB key. Only

<CR> or ccR>cLF> can be selected as an output delim­iter, and EOI is sent simultaneously.

Program codes used for the various settings of the Model
3910 are temporarily stored in the input buffer of the ma­chine. When a delimiter is received, they are interpreted
and executed in the order received. The input buffer can
store up to 14 characters (14 bytes). Note that space, tab,
and semicolons are not stored in the input buffer.

When more than 14 program code characters are re­ceived, the input buffer overflows. When an overflow oc­curs, the input buffer is cleared, and program codes
stored in the buffer are not executed.

In addition, the input buffer is cleared, and subsequent
program codes are not executed when an illegal header
or parameter is found during the interpretation of a pro­gram code.

When interpretation and execution are completed, the in­put buffer is cleared, and the unit is ready to receive the
next program code.

Response to Interface Messages

Table 4-4 summarizes Model 3910 responses to interface

messages.

Table e-4. Response to Interface Messages

IFC

DCL Clears GPIB input/output buffer.

and Clears error status.

SDC Releases SRQ transmission and resets SRQ

Initializes GPIB interface.
Releases specified listener and talker modes.

causes (unit’s operating modes do not
change).

Disables front panel (LOCAL) key.
Goes into local mode (front panel program-

As shown in Figure 4-4, program codes consists of a
header and a parameter. More than one program code
can be sent at a time, up to a maximurn of 14 characters.
Multiple program codes can be separated by a space or
semicolon (;> to improve readability.

There are two general types of program codes: parame­ter-setting messages and inquiry messages. Parameter­setting messages are used for setting parameters or for
sending operating instructions. Inquiry
used for requesting state and parameter setting informa­tion from the instrument.

messages are

4-7

SECTION 4
GPlB Interface

Fivure 4-4.

Prmvam Code Swntar

Parameter Setting Messages

The format of a basic setting message is shown below. In
this example, the start/stop phase is set to -120.0”, and
the waveform is set to a triangle wave.

P=ll&ZQ!J;~~

abc dac

a: Indicates the single letter alphabetic character header.

Either upper-case or lower-case letters can be used.

b: Indicates polarity and can only be used with start/

stop phase. When polarity is omitted, the plus sign (+I
is assumed.

c: Indicates the value of the parameter. If the range of

the parameter is exceeded, program codes thereafter

are ignored.

d: Indicates the semicolon used to separate program

codes for readability. There is no limit on the number
of semicolons, and the semicolon can be omitted. The
semicolon is also ignored and is not stored in the GPIB
input buffer.

For other settings

DorDD

Inquiry Messages

There are no inquiry messages in this instrument. When
the machine is specified as a talker, only a handshake is
performed, and the response is only <CR><LF>+<EOI>.

Service Request

The Model 3910 can request service from the controller

via the SRQ line under the following conditions:

l

FCTN OUT ON/OFF key was operated.

l Out-of-standard program codes, headers were re-

ceived.

When the controller detects SRQ and serial polling is per­formed, the machine sends a status byte to the controller,
and the SRQ signal is set to HIGH.

The status byte can be read by serial polling. If the status
byte is read, bits 2,5, and 6 are reset to 0.

Numeric Format of Parameter-setting Messages

NR1 Format

In the NRl format, numeric values are specified as inte­gers. No decimal point is used in this format. The decimal
point is assumed to be at the end of the last character.

When setting frequency

DDDDDDDDDDD (maximum 11 digits)

When setting phase

*DDDD (maximum 4 digits) OUT.

4-8

Bits in the status byte can be masked so that those particu­lar conditions will not cause an SRQ to occur. To mask
bits, set the corresponding bits to 1 by adding up the deci­mal bit values and sending them with the “K” program
code. For instance, to disable SRQ by masking the FCTN
OUT ON/OFF(4), send the command ‘KS (4 + 1). When
this bit is masked, an SRQ will not occur at FCTN OUT
ON/OFF.

Bit 0 changes each time according to the state of FCTN

SECTIQN4

GPIB In terfuce

If SRQ is not masked, even in the local state, sending of
SRQ is performed if a cause is generated.

When service request is not used, “KO” is set.

Table 4-5. Status Byte

Bit

(M!SB)7 0

6

5

4
3

Description

Set (1) Condition

Always 0 (not used)

RQS

l When SRQ is issued.

Error (SRQ cause) l When out-of-standard program code l When DCL or SDC received

or parameter was received l When status byte was output

Not used Always 0 (not used) Always 0 (not used)
Not used Always 0 (not used) Always 0 (not used)

“KO” is set in the initial state when power is turned on,
and all SRQ causes are masked, and SRQ is not sent.

4.3 MODEL 3910 PROGRAM CODES

Reset (0) Condition

Always 0 (not used)

l When status byte output
l When DCL or SDC received
l When SRQ cause was eliminated

due to SRQ mask set

after SRQ sent

2

FCTNOTJT 0 When FCTN OUT ON/OFF key was l When DCL or SDC received
key was operated operated
(SRQ Cause)

1

Not used Always 0 (not used) Always 0 (not used)

(LSB) 0 State of

FCTN OUT

. FCTNOUTON

l

When status byte was output
after SRQ sent

. FCTNOUTOFF

4-9

SECTION 4

GPIB

Interface

Function

Table 4-6. Model 3910 Main Parameter Setting Messages

Program Code

Header Parameter Operation and Setting Range

BRIpLlTUDE

!ZX=E

-FREQUENCY

A NRl AMPTD range settings

Range: 0 (-2OVp-p)

1 G2vp-p)

2 (-O2Vp-p)
3 (-o.O2Vp-p)

Ex: A2 (-O2Vp-p)

C

D NRl

F

K NIX1 SRQ mask settings

NJ31

NRl Frequency settings (frequency: Hz)

MARK wave number settings
Range: 1-16
Ex:

DC OFFSET ON/OFF settings
Range: 0 (off)

Ex: Dl (DC OFFSET on)

Range: 1 (O.lmHz) to 10000000000(1MHz)
Ex: FlOOOOOOO

Range: 0 (SRQ off)

Ex: K4 (SRQ sent when FCTN OUT ON/OFF key

C2 (MARK wave number 2 wave setting when
BURST, TRIG)

1 (on)

4 (FCTN OUT ON/OFF)
32 (error)
36 (FCTN OUT ON/OFF and error)

is operated)

MODE

FCTNQUT 0 NRl

4-10

M NRl MODE Settings

Range: 0 (CONT)

1 (BURST)
2 (TRIG)
3 (GATE)
4@c)

EX
FCTN OUT ON/OFF settings

Range: 0 (off)

MO (CONT)

1 (on)

Ex. 01 (on)

Function

SECTION 4

GPIB Interface

Model 3910 Main Parameter Setting Messages (Cont.)

Program Code

Header Parameter Operation and Setting Range

START/STOP EHASE

SPACE

TRIG

DUTYYAR

WAVE w NRl FCTN switching

I?

S NRl SPACE wave number settings

T

V

NRl

NRl

NRl

Start/stop phase setting
Range: -3600 (-360.0”) to

+3600 (+360.0’)

Ex:

Range: 1 to 16
Ex:

Trigger signal from GPIB
Range: 0 (trigger off)

Ex: Set from TO + Tl + TO when trigger operated.
DUTY VAR on/off settings

Range: 0 (off)
Ex: Vl (on)

Range: 0 (sine wave)

Ex:

P-1200 (-120.0”)

S2 (SPACE wave number 2 wave setting when BTJR!3T>

1 (trigger on)

1 (on)

1 (triangle wave)
2 (square wave)
3 (rising sawtooth wave)
4 (falling sawtooth wave)
WO (sine

wave)

4-11

SECTION4

GPIB

Interface

4.4 TYPICAL EXECUTION TIMES

The execution times shown in Table 4-7 are the times re-

quired from the reception of the command until execu­tion is complete.

Table 4-7.

Typical Execution Times

It takes about lmsec/byte for the Model 3910 to receive a
command from the GPIB.

Start/Stop Phase
Space
Trig
Duty Var
Wave

P
S
T

V

W

4-12

SECTION 4

GPIB Interface

4.5 SAMPLE PROGRAMS

This paragraph presents three sample programs to con­trol the Model 3910 using an HI? 9816 (or equivalent> per­sonal computer as the controller. The primary address of
the Model 3910 interface is assumed to be 2, and the de­limiter is <CR> cLF>.

Sample program 1 allows you to type in program codes
and send them to the Model 3910.

sample Program 1

10
20 CLEAR 702
30
40
50
60 IF LEN(f%)=O THEN 100
70

80 WAIT 1

90 GOT0 50

100

OUTPUT KBD;CHR$(255);CHR$(75);
REMOTE 702

DIM A$[501

LINPUT "Command String:",A$ ! Prompt for and get command

OUTPUT 702;fl$

END

Sample program 2 sets the SRQ mask to generate an SRQ
on an error condition. An illegal command option is sent,
the Model 3910 is serial polled, and the serial poll byte is
displayed with the error bit (B5) set.

Sample program 3 includes subroutines for sending in­terface messages IFC, DCL, SDC, LLO, and GTL to the
Model 3910 and the subroutines to set REN true or false.

! Clear screen

! Clear GPIB
! Set

! Dimenaion string for input

!

! Send command

! Delay 1

I Repeat

for

Check for

GPIB communication

null

second

iample Program 2 and Results

10 REMOTE 702
20
30
40
50
60

70
80

90

100

110

87 B6 B5 84 B3 82 Bl B0

01100001

OUTPUT 702; "K32"
OUTPUT 702; "A4"
S=SPOLL(702)

IF NOT BIT(S,S) THEN 40
PRINT "B7 B6 B5 B4 B3 BZ
FOR I-7 TO 0 STEP -1 ! Loop 8
PRINT BIT(S,I);

NEXT I
PRINT

END

Bl

B0"

! Set

! Program for SRQ on error
! Try to program

! Serial poll

! Wait for SRQ to occur

! Label

for GPIB

the

bit positions

communication

invalid

the 3910

times

! Display the

bit

positions

option

4-13

SECTION4

GPIB Interface

Sample Program 3

10 !
20 ! IFC
30 ABORT 7
40 RETURN

50 !
60 ! DCL
70 CLEAR 7

80 RETURN

90 !

100 ! SDC

110 CLEAR 702
120 RETURN

130 !
140 I LLO

150 LOCAL LOCKOUT 7
160 RETURN
170 !
180 ! GTL
190 LOCAL 702

200 RETURN

210 !

220 ! REN True
230 REMOTE 7
240 RETURN
250 !
260
270 LOCAL 7
280 RETURN

! REN False

4-14

APPENDIX A

Typical Data

INTRODUCTION

Appendix A provides the typical performance data for

the Model 3910.

This instrument was thoroughly tested, inspected and

certified as meeting its published specifications when it

was shipped from the factory. However, the typical data

represents mean values of measurements for each Model

3910. Thus, measured performance of your Model 3910
may be different than that indicated by the typical data
curves shown here.

A-l

APPENDIXA

lljpical Data

Amplitude

+l

0

-1

Figure A-l.

Amplitude

0.05

0.02 1

100 lk

Frequency (Hz)

Sine Wave Amplitude vs. Frequency Characteristics

I I I111111

Frequency (Hz)

I

100

I I I111111

I I I111111 I I I111111

1.k 10k

10k 1OOk 1M

Sine wave
AMPTD 10 V p-pl5OL-2
1 kHz standard, 50~2 load

I I I111111 I 1111111

I

I I

1OOk

Sinewave

AMPTD 10 V p-p/50&2

1 kHz standard, 5Of2 load

I 111111,”

1M

Figure A-2.

A-2

Tofal Harmonic Distorfion vs. Frequency Characferisfics

Model 3910 and 391Wll Specifications

B.l ELECTRICAL SPECIFICATIONS

Waveforms
DConly,‘L ,il ,%,/l,\

Oscillation Modes

Continuous
Burst

Trigger
Gate GATE!
DC

1 CONT
j BURST

TRIG

DC

APPENDIX B

Continuous oscillation
Continually outputs an integer number of waveform cycles followed by an
integer number of gaps.
Upon receiving a trigger, will output an integer number of waveform cycles.
N-cycles generated while trigger signal is on (i.e. Logic Low). N is an integer.
Outputs a DC level.

Waveform and Frequency Range

Display

Accuracy 1 k30 x lo4 &3Oppm)

‘L , i-t

% ,/l ,U ,

Maximum 11 columns, resolution O.lmHz (constant)

(Duty fixed)

IL

Output Characteristics

Maximum Output

DC only
Amplitude Frequency
Characteristics

AMPTD Ranges
AMPTD Variable Adiustment
spectrum Purity

Square Wave Characteristics

Amplitude accuracy referenced to amplitude at lkHz, DC offset off, 5OQ load, lOVp-p output

Sine wave M.ldB @ 1OkHz

Triangle wave

Souare wave

(Dutyvariable)

flOV/open, i5V/5OQ load

f IdB, -3dB @ 1MHz

0.1mHz to 1MHz

1 o.hlH!z to 1DDkHz

Specifications subject to change without notice.

ELECTRICAL SPECIFICATIONS (Cont.)

Output Characteristics (Cont.)

Power-up state Function output turns on. Can be switched off by changing internal jumper.
Output Impedance 5OQ ti%, unbalanced (open when function output is off, can be switched to short by changing

il.lmDer)

Connector BNC plug, front panel

sync output

Output Voltage
Connector

Trigger, Gate Oscillation

Trigger Source
Input Voltage
Start/Stop Phase

Memory

Parameters Stored in
Non-volatile Memorv

1 Number of Sets I Stores 1 set of uarameters.

Battery Backup

1 TTL level (5lQ in series with a 74LSO0 output)
1 BNC plug, front panel

External trigger only. Front panel BNC plug or push-button switch.

‘lTL level (74HC14 input with 5.lkQ pull-up resistor). Minimum pulse width 200~s.

Setting range -1-360.0” to -360.0”

Display

Jitter 15ons

Frequency, FCTN (function), Mode, AMM’D range, Duty var on/off, GPIB address, DC offset on/off.

Start/Stou chase, Mark wave number, Suace wave number.

30 days or more after full charge (stored at room temperature)

Maximum 4 digits + negative display, resolution 0.1” (constant)

I

1 Modify Method

1 Left/Eight Cursor Button and Modify Dial

Display Functions

7 Segment LED Oscillation frequency, GPIB address (only when GPIB option is installed), start stop phase,

mark wave number, space wave number.

Presets

If the non-volatile memory fails and the 3910 is cleared, the parameters will be set as follows:
Frequency 1.OOoMlookI-Iz ­FCTN OUT On (can be set to off by switching internal short plug)
AMFTD range
DC offset
Dutv var
Display select
FCTN (function)
GPIB Address
Mark Wave Number
Space Wave Number
Mode
Start Stop Phase ( 0’ (cursor is 0.1’ column)

-O.o2vp-p
/ Off
/ Fxd
1 Frequency display
I Sine
1 2 (3910/11 only)
I 1
/ 1
1 CONT.

B.2 GPIB INTERFACE (3910/l 1 ONLY)

GPIB Interface

Functions
Data
Delimiter

Address
Output Driver

Local Key ) Return to local function
Connector IEEE-488 24 pin GPIB connector, rear panel

SHl, AHl, T6, L4, SRl, RLI, Pl’O, DCI, DTO, CO
ASCII (7-bit)

Reception 1 CR, CR/IS, CR + EOI, CR/LF + EOI, or EOI
0 - 30 (set by modify dial from panel face)
DIOl - DIOS, NDAC, NRFD, SRQ 1 Open collector
DAV, EOI I Three-state

B.3 GENERAL

Signal Ground
Power Supply

Ambient Temperature and
Humidity
External Dimensions
Weight

The grounding pins of all input/output connectors are connected to the chassis.
Voltage
Frequency
Power Consumption
Operating Range
When Storage
Excludine Proiections

1 ADDrOx.

3.2ke.. 6 lbs.. 12 oz.

AC lOOV, 12OV, 22OV, 24(fflO% switch, maximum voltage 250V.
48H.z - 62II.z
Approx. 25VA
0’ - 4O”C, 10 - 90% RH (no condensation)

-10” to 5O”C, 10% to 80% RH (no condensation)
216 0 x 132.5 (HI x 350 (D) mm

7

Figure B-l. Outer Dimensions

of

fhe Model 3910

Index

B

Basic Controller Functions, 4-3
Basic Listener Functions, 4-3
Basic Talker Functions, 4-3
Bus Driver, 4-6
Bus Line Signals, 4-l
burst mode, 3-10

C

Codes, 4-6
Cooling, 2-l
continuous mode, 3-9

D

DC mode, 3-11
DC Offset, 3-8
Delimiter, 4-7
Duty Cycle, 3-8

E

Error Codes, 3-7

G

GPIB Handshaking, 4-2

GPIB Overview, 4-l

GPIB Primary Address, 4-7

gate mode, 3-10

H

Handling Precautions, 2-2

I

Input Connection, 3-5

Inquiry Messages, 48

Installation, 2-l

Interface Functions, 4-6

L

LINE Voltage Selector Switch, 2-2
Line Fuse, 2-2
Line Power Supply, 2-2
Line Receptacle Connection, 2-2

N

Numeric Format, 4-8

0

Operating Examples, 2-4

Optional Accessories, l-3

Oscillation Mode Selection, 3-9
Output Amplitude, 3-8

output coMections,

3-5

P

Parameter Setting Messages, 4-8
Program Codes, 47,49
phase setting, 3-11

F

Features, 1-l
Frequency Setting, 3-7
Front Panel Description, 3-l

M

Major GPIB Specifications, 4-l

Manual Addenda, l-2

Multi-line Interface Messages, 4-3

mark wave setting, 3-13

R

Rear Panel Description, 3-4
Repacking, l-2
Response to Interface Messages, 47

Safety Terms and Symbols, l-2
Sample Programs, 413
Service Request, 4-8
Square-Wave Duty Cycle, 3-8
Start/Stop Phase, 3-11
Startup, 3-6
Status Byte, 4-9
Synchronous Output, 3-9
space wave setting, 3-13

T

Trigger Parameters, 3-11
Typical Data, A-l
Typical Execution Times, 4-12
Typical Test Connections, 2-3
trigger mode, 3-10

u

Unpacking, l-2

v

vents, 2-l

W

Warranty, l-2
Waveform Selection, 3-8

SERVICE FORM

Model No.

Serial No.

Name and Telephone No.

Company

List all control settings, describe problem and check boxes that apply to problem.

q

q

Intermittent

EIIJZE failure

q

Front panel operational

Display or output (circle one)

aDrifts
nunstable

q

overload

q

calibration only

0 Data required

(attach any additional sheets as necessary.)

q

Analog output follows display

q

Obvious problem on power-up

aAll ranges or functions are bad

nUnable to zero

q

Will not read applied input

q

Certificate of Calibration required

Particular range or function bad; specify

q

Batteries and fuses are OK

q

Checked all cables

Date

Show a block diagram of your measurement system including all instruments connected (whether power is turned on or not).
Also, describe signal source.

Where is the measurement being performed?

What power line voltage is used?
Relative humidity?

Any additional information. (If special modifications have been made by the user, please describe.)

(factory, controlled laboratory, out-of-doors, etc.)

Ambient Temperature?

Other?

“F

Be sure to include your name end phone number on this service form.

Instruments Division, Keithley Instruments, Inc. l 28775 Aurora Road l Cleveland, Ohio 44139 l [phone] * Fax: [phone]

WEST GERMANY: Keitbky Instruments GmbH . Heiglhofstr. 5. Munchen 70 l 089-7lOOZ-0 l T&x: 57-12160 * Fax: [phone]
GREAT BRITAIN: Keitbley Instruments, Ltd. l The Mnster l 58, Portman Road l Reading, Berkshire RG 3 1F.A
FRANCE: Keitbky Instruments SARL -3 Allee ds Gays l E.P. 60 l 91124 Palaiseau/Z.L . I-6-0115 155 l Telex: 600 933 l Fax: I-6aI7726
NEIMERLANDS:
SWITZERLAND: Keitbky
AUSTRIA:
ITALY: Keitbley Instruments SRL . Vi&S. Gimignano 4/A -20146 Milan0 l 02-4120360 or 02-4156540 0 Fax: [phone]

Keitbky Instruments BV l Avelingen West 49 l 4202 MS Gorinchem l P.O. BOX 559 l 42W AN Gorinchem l 0X330-35333 l Telex 24 684 l Fax 0X30-30821

Instruments

Keithky Instruments GesmbH l Rosenhugelstrasse 12. A-1120 Vienna l LO222.J 84 65 48 l Telex: 131677 l Fax: [phone]

SA l Kriesbachstr. 4 l 8600 Dubendorf l 01-821-9444 l Telex: 828 4R l Fax: [phone]

l

01144 734 575 666 l Fax: [phone]