National Instruments NI 2590, NI 2591 User Manual

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Computer-Based Instruments

NI 2590/2591 User Manual

November 2000 Edition

Part Number 322387B-01

Worldwide Technical Support and Product Information

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For further support information, see the Technical Support Resources appendix. To comment on the documentation, send e-mail to techpubs@ni.com

Important Information

Warranty

The NI 2590 and NI 2591 switch modules and accessories are warranted against defects in materials and workmanship for a period of one year from the date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace equipment that proves to be defective during the warranty period. This warranty includes parts and labor.

The media on which you receive National Instruments software are warranted not to fail to execute programming instructions, due to defects in materials and workmanship, for a period of 90 days from date of shipment, as evidenced by receipts or other documentation. National Instruments will, at its option, repair or replace software media that do not execute programming instructions if National Instruments receives notice of such defects during the warranty period. National Instruments does not warrant that the operation of the software shall be uninterrupted or error free.

A Return Material Authorization (RMA) number must be obtained from the factory and clearly marked on the outside of the package before any equipment will be accepted for warranty work. National Instruments will pay the shipping costs of returning to the owner parts which are covered by warranty.

National Instruments believes that the information in this document is accurate. The document has been carefully reviewed for technical accuracy. In the event that technical or typographical errors exist, National Instruments reserves the right to make changes to subsequent editions of this document without prior notice to holders of this edition. The reader should consult National Instruments if errors are suspected. In no event shall National Instruments be liable for any damages arising out of or related to this document or the information contained in it.

XCEPT AS SPECIFIED HEREIN,NATIONAL INSTRUMENTS MAKES NO WAR RANTIES, EXPRESS OR IMPLIED, AND SPECIFICALLY DISCLAIMS ANY

WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE

NEGLIGENCE ON THE PART OF

INSTRUMENTS WILL NOT BE LIABLE FOR DAMAGES RESULTING F ROM LOSS OF DATA, PROFITS, USE OF PRODUCTS, OR INCIDENTAL OR

CONSEQUENTIAL DAMAGES

apply regardless of the form of action, whether in contract or tort, including negligence. Any action against National Instruments must be brought within one year after the cause of action accrues. National Instruments shall not be liable for any delay in performance due to causes beyond its reasonable control. The warranty provided herein does not cover damages, defects, malfunctions, or service failures caused by owner’s failure to follow the National Instruments installation, operation, or maintenance instructions; owner’s modification of the product; owner’s abuse, misuse, or negligent acts; and power failure or surges, fire, flood, accident, actions of third parties, or other events outside reasonable control.

NATIONAL INSTRUMENTS SHALL BE LIMITED TO THE AMOUNT THERETOFORE PAID BY THE CUSTOMER.NATIONAL

, EVEN IF ADVISED OF THE POSSIBILITY THEREOF. This limitation of the liability of National Instruments will

.CUSTOMER’S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT OR

Copyright

Under the copyright laws, this publication may not be reproduced or transmitted in any form, electronic or mechanical, including photocopying, recording, storing in an information retrieval system, or translating, in whole or in part, without the prior written consent of National Instruments Corporation.

Trademarks

CVI™,IVI™,LabVIEW™, National Instruments™,ni.com™,andPXI™are trademarks of National Instruments Corporation.

Product and company names mentioned herein are trademarks or trade names of their respective companies.

WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS

(1) NATIONAL INSTRUMENTS PRODUCTS ARE NOT DESIGNED WITH COMPONENTS AND TESTING FOR A LEVEL OF RELIABILITY SUITABLE FOR USE IN OR IN CONNECTION WITH SURGICAL IMPLANTS OR AS CRITICAL COMPONENTS IN ANY LIFE SUPPORT SYSTEMS WHOSE FAILURE TO PERFORM CAN REASONABLY BE EXPECTED TO CAUSE SIGNIFICANT INJURY TO A HUMAN.

(2) IN ANY APPLICATION, INCLUDING THE ABOVE, RELIABILITY OF OPERATION OF THE SOFTWARE PRODUCTS CAN BE IMPAIRED BY ADVERSE FACTORS, INCLUDING BUT NOT LIMITED TO FLUCTUATIONS IN ELECTRICAL POWER SUPPLY, COMPUTER HARDWARE MALFUNCTIONS, COMPUTER OPERATING SYSTEM SOFTWARE FITNESS, FITNESS OF COMPILERS AND DEVELOPMENT SOFTWARE USED TO DEVELOP AN APPLICATION, INSTALLATION ERRORS, SOFTWARE AND HARDWARE COMPATIBILITY PROBLEMS, MALFUNCTIONS OR FAILURES OF ELECTRONIC MONITORING OR CONTROL DEVICES, TRANSIENT FAILURES OF ELECTRONIC SYSTEMS (HARDWARE AND/OR SOFTWARE), UNANTICIPATED USES OR MISUSES, OR ERRORS ON THE PART OF THE USER OR APPLICATIONS DESIGNER (ADVERSE FACTORS SUCH AS THESE ARE HEREAFTER COLLECTIVELY TERMED “SYSTEM FAILURES”). ANY APPLICATION WHERE A SYSTEM FAILURE WOULD CREATE A RISK OF HARM TO PROPERTY OR PERSONS (INCLUDING THE RISK OF BODILY INJURY AND DEATH) SHOULD NOT BE RELIANT SOLELY UPON ONE FORM OF ELECTRONIC SYSTEM DUE TO THE RISK OF SYSTEM FAILURE. TO AVOID DAMAGE, INJURY, OR DEATH, THE USER OR APPLICATION DESIGNER MUST TAKE REASONABLY PRUDENT STEPS TO PROTECT AGAINST SYSTEM FAILURES, INCLUDING BUT NOT LIMITED TO BACK-UP OR SHUT DOWN MECHANISMS. BECAUSE EACH END-USER SYSTEM IS CUSTOMIZED AND DIFFERS FROM NATIONAL INSTRUMENTS' TESTING PLATFORMS AND BECAUSE A USER OR APPLICATION DESIGNER MAY USE NATIONAL INSTRUMENTS PRODUCTS IN COMBINATION WITH OTHER PRODUCTS IN A MANNER NOT EVALUATED OR CONTEMPLATED BY NATIONAL INSTRUMENTS, THE USER OR APPLICATION DESIGNER IS ULTIMATELY RESPONSIBLE FOR VERIFYING AND VALIDATING THE SUITABILITY OF NATIONAL INSTRUMENTS PRODUCTS WHENEVER NATIONAL INSTRUMENTS PRODUCTS ARE INCORPORATED IN A SYSTEM OR APPLICATION, INCLUDING, WITHOUT LIMITATION, THE APPROPRIATE DESIGN, PROCESS AND SAFETY LEVEL OF SUCH SYSTEM OR APPLICATION.

Compliance

FCC/Canada Radio Frequency Interference Compliance*

Determining FCC Class

The Federal Communications Commission (FCC) has rules to protect wireless communications from interference. The FCC places digital electronics into two classes. These classes are known as Class A (for use in industrialcommercial locations only) or Class B (for use in residential or commercial locations). Depending on where it is operated, this product could be subject to restrictions in the FCC rules. (In Canada, the Department of Communications (DOC), of Industry Canada, regulates wireless interference in much the same way.)

Digital electronics emit weak signals during normal operation that can affect radio, television, or other wireless products. By examining the product you purchased, you can determine the FCC Class and therefore which of the two FCC/DOC Warnings apply in the following sections. (Some products may not be labeled at all for FCC; if so, the reader should then assume these are Class A devices.)

FCC Class A products only displaya simplewarning statement of one paragraph in length regarding interference and undesired operation. Most of our products are FCC Class A. The FCC rules have restrictions regarding the locations where FCC Class A products can be operated.

FCC Class B products display either a FCC ID code, starting with the letters EXN, or the FCC Class B compliance mark that appears as shown here on the right.

Consult the FCC web site

http://www.fcc.gov

FCC/DOC Warnings

This equipment generates and uses radio frequency energy and, if not installed and used in strict accordance with the instructions in this manual and the CE Mark Declaration of Conformity**, may cause interference to radio and television reception. Classification requirements are the same for the Federal Communications Commission (FCC) and the Canadian Department of Communications (DOC).

Changes or modifications not expressly approved by National Instruments could void the user’s authority to operate the equipment under the FCC Rules.

Class A

Federal Communications Commission

This equipment has been tested and found to comply with the limits for a Class A digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference when the equipment is operated ina commercial environment. This equipment generates, uses, and can radiate radio frequency energy and, if not installed and used in accordance with the instruction manual, may cause harmful interference to radio communications. Operation of this equipment in a residential area is likely to cause harmful interference in which case the user will be required to correct the interference at his own expense.

for more information.

Canadian Department of Communications

This Class A digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations.

Cet appareil numérique de la classe A respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.

Class B

Federal Communications Commission

This equipment has been tested and found to comply with the limits for a Class B digital device, pursuant to part 15 of the FCC Rules. These limits are designed to provide reasonable protection against harmful interference in a residential installation. This equipment generates, uses and can radiate radio frequency energy and, if not installed and used in accordance with the instructions, may cause harmful interference to radio communications. However, there is no guarantee that interference will not occur in a particular installation. If this equipment does cause harmful interference to radio or television reception, which can be determined by turning the equipment off and on, the user is encouraged to try to correct the interference by one or more of the following measures:

• Reorient or relocate the receiving antenna.

• Increase the separation between the equipment and receiver.

• Connect the equipment into an outlet on a circuit different from that to which the receiver is connected.

• Consult the dealer or an experienced radio/TV technician for help.

Canadian Department of Communications

This Class B digital apparatus meets all requirements of the Canadian Interference-Causing Equipment Regulations.

Cet appareil numérique de la classe B respecte toutes les exigences du Règlement sur le matériel brouilleur du Canada.

European Union - Compliance to EEC Directives

Readers in the EU/EEC/EEA must refer to the Manufacturer's Declaration of Conformity (DoC) for information** pertaining to the CE Mark compliance scheme. The Manufacturer includes a DoC for most every hardware product except for those bought for OEMs, if also available from an original manufacturer that also markets in the EU, or where compliance is not required as for electrically benign apparatus or cables.

* Certain exemptions may apply in the USA, see FCC Rules §15.103 Exempted devices,and§15.105(c).

Also available in sections of CFR 47.

** The CE Mark Declaration of Conformity will contain important supplementary information and instructions

for the user or installer.

Conventions

The following conventions are used in this manual:

<> Angle brackets that contain numbers separated by an ellipsis represent a

range of values associated with a bit or signal name—for example, DBIO<3..0>.

This icon denotes a note, which alerts you to important information.

This icon denotes a caution, which advises you of precautions to take to avoid injury, data loss, or a system crash.

This icon denotes a warning, which advises you of precautions to take to avoid being electrically shocked.

italic Italic text denotes variables, emphasis, a cross reference, or an introduction

to a key concept. This font also denotes text that is a placeholder for a word or value that you must supply.

monospace

Text in this font denotes text or characters that you should enter from the keyboard, sections of code, programming examples, and syntax examples. This font is also used for the proper names of disk drives, paths, directories, programs, subprograms, subroutines, device names, functions, operations, variables, filenames and extensions, and code excerpts.

Chapter 1 Routing Signals with Your NI 2590/2591

About the NI 2590/2591 ................................................................................................1-1

Triggers............................................................................................................1-1

RF Switching Precautions..............................................................................................1-2

Contact Protection.......................................................................................................... 1-2

Connecting Signals ........................................................................................................1-3

NI 2590 Front Connector.................................................................................1-3

NI 2591 Front Connector.................................................................................1-4

Software Choices ...........................................................................................................1-5

NI-SWITCH Driver Software .........................................................................1-5

National Instruments Application Software .................................................... 1-5

Third-Party Software.......................................................................................1-6

Cabling and Accessory Requirements ...........................................................................1-6

Chapter 2 NI 2590/2591 Operation

Safety Instructions .........................................................................................................2-1

Functional Overview...................................................................................................... 2-2

Relay Operation .............................................................................................................2-5

NI 2590 Operation...........................................................................................2-5

NI 2591 Operation...........................................................................................2-5

Switch Control Circuitry................................................................................................2-6

Random Scanning .......................................................................................................... 2-6

PXI Interface..................................................................................................................2-7

PXI Triggers ....................................................................................................2-7

External Trigger Input....................................................................... 2-7

Scanner Advanced.............................................................................2-7

Modes................................................................................................2-8

Initiating Scanning........................................................................................... 2-8

Multiboard Triggering .....................................................................................2-8

Appendix A Specifications

Appendix B Servicing Your Module

Contents

Appendix C Common Questions

Appendix D Technical Support Resources

Glossary

Index

NI 2590/2591 User Manual viii ni.com

Routing Signals with Your NI 2590/2591

This manual describes the electrical and mechanical characteristics of the

NI 2590, a 1 × 4, 50 Ω, 1.3 GHz multiplexer module, and the NI 2591,

a1× 4, 50 Ω, 4.0 GHz multiplexer module, for the PXI bus. It contains

information concerning their installation and operation.

About the NI 2590/2591

This section summarizes the features and operation of the NI 2590/2591

switch module; refer to Chapter 2, NI 2590/2591 Operation,formore

complete details. In addition, refer to Appendix A, Specifications,

for detailed specifications of the switch module.

The NI 2590/2591 are general-purpose, 4-channel, high-bandwidth

multiplexing switches.

The NI 2590 uses single-pole double-throw high-bandwidth relays capable

of switching signals from DC to 1.3 GHz. The characteristic impedance of

the channels is 50 Ω. The maximum rated voltage of the switch is 24 VDC,

and the maximum rated current is 1 ADC.

The NI 2591 uses a self-contained relay module consisting of three

high-bandwidth relays capable of switching signals from DC to 4 GHz. The

characteristic impedance of the channels is 50 Ω. The maximum rated DC

voltage of the module is 30 V. The maximum rated current is 0.33 A.

Triggers

Two triggers are used for handshaking between the NI 2590/2591 switches

and other PXI instruments. The scanner advanced trigger indicates when

the module has closed all the necessary switches for the next scan and the

switches have settled, or debounced.

Chapter 1 Routing Signals with Your NI 2590/2591

The external trigger input trigger is generated by another instrument or by software and causes the NI 2590/2591 to advance to the next entry in the scan list. The triggers can be routed to any of the PXI TTL triggers or to the PXIstartrigger.

Refer to Chapter 2, NI 2590/2591 Operation, for more information on triggers.

RF Switching Precautions

The NI 2590/2591 is a reflective switch, meaning that any channels not switched to the common channel are unterminated, and any signal on an unterminated channel will be reflected to its source. For most low-power switching applications this is not a problem. However, operation with an unterminated output can damage some high-power RF sources. Consult your RF source documentation for more information about connecting to unterminated channels.

Caution

PXI chassis before removing the NI 2590/2591 from the chassis. Observe electrostatic discharge handling precautions during and after removal of the module, or when connecting and disconnecting signals on the front panel.

Warning

exceed the maximum voltage for the NI 2590/2591 can result in an electrical shock hazard and damage to the switch module and any or all of the modules connected to the PXI backplane. National Instruments is not liable for any damages or injuries resulting from exceeding maximum voltage ratings. Refer to Appendix A, Specifications, for information.

Always disconnect all signals from the front connectors and power down the

Do not exceed the channel-to-ground voltage rating. Any connections that

Contact Protection

Caution

when operated with no signal or a very small signal present. At full rated power—1Aat 24 VDC for the NI 2590 and 0.33 A at 30 VDC for the NI 2591—the life of the switch is downgraded to 100,000 operations. If your setup allows, it is always best to turn off the input signals connected to the switch module during the switching operation to avoid contact arcing within the switch. Switching large inductive loads can also cause contact arcing. In such instances, install a flyback diode or varistor across the inductance to protect the switch.

The contacts of the relay are rated for a life of 5 × 106mechanical operations

NI 2590/2591 User Manual 1-2 ni.com

Connecting Signals

The front of the NI 2590 module has five “push-on” SMB connectors for

signal connections. The NI 2591 has five SMA female connectors. The

center connection, labeled COM, is connected in a through path to one of

the other four connections depending on the software instructions sent to

the switch.

NI 2590 Front Connector

The following diagram shows the NI 2590 front connector. Table 1-1

describes the connector signals.

Chapter 1 Routing Signals with Your NI 2590/2591

2590

1×4 1.3 GHz Mux

CH0

CH1

COM

CH2

CH3

Figure 1-1. NI 2590 Front Connector

Chapter 1 Routing Signals with Your NI 2590/2591

NI 2591 Front Connector

The following diagram shows the NI 2591 front connector. Table 1-1 describes the connector signals.

2591

1×4 4 GHz Mux

C O M

Figure 1-2. NI 2591 Front Connector

Table 1-1. Front Connector Signal Description

Signal Name Type Description

CH<0..3> Input/Output Channels—Where signals are connected to the switch

module

COM Input/Output Common—The common for the respective channel

NI 2590/2591 User Manual 1-4 ni.com

Chapter 1 Routing Signals with Your NI 2590/2591

Software Choices

You have several options to choose from when programming your National Instruments switch module. You can use the NI-SWITCH driver software or National Instruments application software.

NI-SWITCH Driver Software

The NI-SWITCH instrument driver is an Interchangeable Virtual Instrument (IVI)-compliant instrument driver that is bundled with the module at no cost.

NI-SWITCH features a set of operations and attributes that exercise all the functionality of the switching hardware, including configuration, opening/closing, and scanning. In addition, NI-SWITCHNI-SWITCH comes with an interactive soft front panel and online documentation.

NI-SWITCH eliminates the need to understand complex register programming and interrupt handling in the Microsoft operating systems, and frees you to focus on creating your test system.

National Instruments Application Software

LabVIEW and LabWindows/CVI are innovative program development software packages for data acquisition and control applications. LabVIEW uses graphical programming, whereas LabWindows/CVI enhances traditional programming languages. Both packages include extensive libraries for data acquisition, instrument control, data analysis, and graphical data presentation. Using LabVIEW or LabWindows/CVI can significantly reduce the development time for your data acquisition and control application.

LabVIEW features interactive graphics, a state-of-the-art user interface, and a powerful graphical programming language. The LabVIEW NI-SWITCH VI Library, a series of virtual instruments (VIs) for using LabVIEW with National Instruments switch hardware, is included with the NI-SWITCH driver.

LabWindows/CVI features interactive graphics, a state-of-the-art user interface, and uses the ANSI standard C programming language. The LabWindows/CVI NI-SWITCH Library, a series of functions for using LabWindows/CVI with National Instruments switch hardware, is included with the NI-SWITCH driver.

Chapter 1 Routing Signals with Your NI 2590/2591

Third-Party Software

The NI-SWITCH instrument driver also includes support files for Microsoft Visual C++ and Microsoft Visual Basic. See the NI-SWITCH Software Readme File for version support information.

Cabling and Accessory Requirements

National Instruments recommends the use of cables and accessories with 50 Ω characteristic impedance with the NI 2590/2591.

NI 2590/2591 User Manual 1-6 ni.com

NI 2590/2591 Operation

This chapter contains safety instructions and a functional overview of the NI 2590/2591 switch modules. It also explains the operation of each functional unit making up the switch module.

Safety Instructions

Cautions

instrument can become impaired if the instrument becomes damaged in any way. If the instrument is damaged, do not use it until service-trained personnel can check its safety. If necessary, return the instrument to National Instruments for service and repair to ensure that its safety is not compromised.

Do not operate this instrument in a manner that contradicts the information specified in this document. Misuse of this instrument could result in a shock hazard.

Do not substitute parts or modify equipment beyond what is described in Appendix B,

Servicing Your Module. Because of the danger of introducing additional hazards, do not

install unauthorized parts or modify the instrument. Return the instrument to National Instruments for service and repair to ensure that its safety is not compromised.

Connections that exceed any of the maximum signal ratings on the NI 2590/2591 can create a shock or fire hazard or can damage any or all of the devices connected to the NI 2590/2591. National Instruments is not liable for any damages or injuries resulting from incorrect signal connections.

Clean instrument and accessories by brushing off light dust with a soft, nonmetallic brush. Remove other contaminants with a stiff nonmetallic brush. The unit must be completely dry and free from contaminants before returning to service.

Do not operate damaged equipment. The safety protection features built into this

Chapter 2 NI 2590/2591 Operation

Functional Overview

The following block diagrams illustrate the key functional components of the NI 2590 and NI 2591 switch modules.

The major components of the NI 2590/2591 are as follows:

• General-purpose high-frequency relays

• Switch control circuitry

• Random scanning

• PXIbus interface

• Triggers

NI 2590/2591 User Manual 2-2 ni.com

CH3

CH2

Front Panel

COM

CH1

Chapter 2 NI 2590/2591 Operation

CH0

MUX23

Triggers

MUX0123

Relay Control

MUX01

Scan Memory

PXI

Interface

PXIbus Connector

Figure 2-1. NI 2590 Module Block Diagram

Chapter 2 NI 2590/2591 Operation

CH3

CH2

Front Panel

COM

DECODER

CH1

Control

Lines

Scan Memory

CH0

High–

Frequency

Relay

4 GHz

Relay Module

Triggers

Relay Control

PXI Bus Connector

PXI

Interface

Figure 2-2. NI 2591 Module Block Diagram

NI 2590/2591 User Manual 2-4 ni.com

Relay Operation

NI 2590 Operation

The NI 2590 has four channels, CH0 through CH3, any one of which can be connected to the single common channel (COM) by closing the appropriate relays.

You can control the relays individually, or you can use higher-level commands to energize the correct relays to connect a channel (such as CH0) to COM. Only one channel can be connected to the common channel at any time, and it is not possible to connect one channel to another channel bypassing the common channel.

The NI 2590 relays are single-side stable. When power is removed from the relay coil, the relay returns to its de-energized state. When all three relays are de-energized, the default connection is from CH0 to COM, as shown in Figure 2-1. To connect CH2 to COM, you energize MUX0123; to connect CH3 to COM, you energize MUX0123 and MUX23. You can specify the channel to connect to COM and let the NI-Switch driver energize the appropriate relays for you. Refer to the NI-SWITCH Software User Manual for further information.

Chapter 2 NI 2590/2591 Operation

NI 2591 Operation

The NI 2591 is very similar to the NI 2590 in some respects, but different in others. The NI 2591 has 4 channels, CH0 through CH3, any one of which can be connected to the single COM by closing the appropriate relays.

The NI 2591 does not allow for control of the individual relays. You must use the high-level commands to connect the channels, such as CH2 to COM. Only one channel can be connected to the common channel at any time, and it is not possible to connect one channel to another channel, bypassing the common channel. The default (power off) connection of the NI 2591 is CH3 to COM. Refer to Figure 2-2 to see how the connections in the NI 2591 are made.

Chapter 2 NI 2590/2591 Operation

Switch Control Circuitry

The switch control circuitry (SCC) is responsible for opening and closing relays on the NI 2590/2591. You can load commands for the SCC into scan memory using the driver software you received with your kit. Consult the online help or your software documentation for specific information on the appropriate commands. There are two reasons for storing the commands in memory before the SCC can process them:

• Both the operate and release times for the NI 2590/2591 are 15 ms. Using memory storage, the software can send multiple commands to the SCC without having to wait for a relay action to complete.

• The memory is used to store a scan list necessary for hardware random scanning.

Random Scanning

The NI 2590/2591 can perform random scanning. In random scanning, the switch module can open or close relays in any order.

The scan list is downloaded to onboard memory. Commands in the scan list can perform the following actions:

• Open or close relays

• Wait for an external trigger

• Generate a scanner advanced trigger

• Generate a breakpoint interrupt

You can use the driver software to configure the switch module for continuous or one-time scanning. In continuous scanning, the switch module cycles through the scan list until you disable scanning. For one-time scanning, the switch module runs through the scan list only once.

You can also use software commands to clear the scan list or reset it to the beginning at any time.

The onboard control logic for the NI 2590/2591 switch module gives you direct access to open and close the relays, and also the ability to download up to 1,024 random scanning instructions. The software included with the module automatically configures the NI 2590/2591 and downloads the scan list to hardware for you. The scan list itself downloads directly into the memory of the module to deliver the fastest scan possible with no controller

NI 2590/2591 User Manual 2-6 ni.com

PXI Interface

PXI Triggers

Chapter 2 NI 2590/2591 Operation

intervention. You can configure the switch module to process the scan list once or to continuously loop through the scan list.

You can configure and control your NI 2590/2591 switch module through the PXI interface, taking advantage of PXI features. The NI 2590/2591 uses the PXI TTL triggers to synchronize scanning with a measurement device such as the NI 5102 (PXI) 20 MS/s oscilloscope, or the NI 5411 for PXI arbitrary waveform generator.

External Trigger Input

The NI 2590/2591 can use an external trigger input to advance between scan setups in a scan list. Using the driver software, you can configure the switch module to route the external trigger from any of the PXI TTL trigger lines or the PXI star trigger. Alternatively, you can use a software command to trigger the switch module.

All external trigger lines are compatible with TTL voltage levels and are edge sensitive. The minimum pulse width from the PXI TTL triggers and PXI star trigger is 70 ns.

Scanner Advanced

The NI 2590/2591 can generate a scanner advanced trigger to indicate when the switch module is set up and ready to take measurements. Using the driver software, you can configure the switch module to route the scanner advanced (SCANADV) trigger to any PXI TTL trigger line or to the PXI star trigger. You can configure the switch module to generate the SCANADV trigger when a relay has settled (or debounced).

Because the NI 2590/2591 has open-collector drivers on the PXI TTL trigger lines, you can have multiple switch modules using the same trigger line in the multiboard SCANADV mode.

Chapter 2 NI 2590/2591 Operation

Modes

SCANADV has two modes of operation. In its default mode, the SCANADV trigger asserts for 1 µs after the relay has debounced. You can also configure the switch module for handshaking mode, in which the SCANADV trigger goes high after a relay settles, and the SCANADV trigger goes low after the external trigger input asserts. You can use this handshaking mode for multiboard scanning.

Note

The NI 2590/2591 ignores external triggers when it is not in a wait-for-trigger state

while scanning.

Initiating Scanning

When you use the NI 2590/2591 to initiate a scan, make sure the measurement device is armed (waiting for trigger) before enabling scanning on the switch module. Enabling scanning causes the first switch(es) in the scan list to close and generates a scanner advanced trigger after the relay switches have settled or debounced.

When you use the measurement device to initiate a scan, make sure scanning is enabled on the NI 2590/2591 before the measurement device starts to take measurements. This ensures that the switch module has the correct signal routed and that the switch module is waiting for an external trigger from the measurement device.

Always configure the triggers in a system before configuring the measurement device or the NI 2590/2591 for scanning. When triggers are configured, a state change or pulse could occur on the trigger line. This is also possible when you reset the switch module.

Multiboard Triggering

You can use multiple NI 2590/2591 switch modules—or multiple other National Instruments switch modules such as the NI 2503—together in conjunction with an instrument such as a National Instruments oscilloscope/digitizer. In multiple switch-module systems, be sure to identify one switch module as the master switch module.

All other switch modules for the system are identified as slave switch modules. The master switch module can route an external trigger from the front connector to a PXI backplane trigger. In addition, the master switch module can route the SCANADV trigger from the PXI backplane to either the front connector or another backplane trigger. This functionality makes

NI 2590/2591 User Manual 2-8 ni.com

Chapter 2 NI 2590/2591 Operation

it possible to wire external triggers from/to only one switch module in the system, which simplifies the wiring scheme.

Note

The NI 2590/2591 does not support triggers on the front panel connector. If the trigger signal is external to the chassis, you must use a different National Instruments switch module, such as the NI 2503, as the master switch module.

For more information, refer to the NI-SWITCH Software User Manual.

Specifications

This appendix lists the specifications for the NI 2590/2591 switch module. These specifications are typical at 25 °C unless otherwise noted.

NI 2590

Input Characteristics

Number of relays.................................... 3

Common-mode voltage

Channel to earth ..............................24 VDC

Maximum switching voltage

AC................................................... 24 V

DC................................................... 24 VDC

Maximum switching capacity per channel

DC................................................... 1 A at 24 V

AC................................................... 1 A

rms

at 24 V

Maximum switching

power per channel .................................. 24 W

Contact on resistance (initial) ................ 100 mΩ max

Contact material ..................................... Gold-clad silver

RF Performance Characteristics

Characteristic impedance (Z0)................ 50 Ω

Insertion loss at:

< 100 MHz ......................................< 0.4 dB

< 500 MHz ......................................< 0.9 dB

< 1.3 GHz........................................< 1.5 dB

Appendix A Specifications for NI 2590

VSWR at:

< 100 MHz.......................................< 1.15

< 500 MHz.......................................< 1.35

< 1.3 GHz ........................................< 1.5

Isolation:

< 500 MHz.......................................< –62 dB

< 1.3 GHz ........................................< –50 dB

Risetime ..................................................< 300 ps

Signal delay ............................................< 3 ns

Maximum RF carry power

at 900 MHz .............................................10 W

Note

Refer to the cautions and warning in the RF Switching Precautions and Contact

Protection sections of Chapter 1, Routing Signals with Your NI 2590/2591, for important

information about using your NI 2590/2591 with high-power signals.

Dynamic Characteristics

Relay operate time (at 20 °C)

Typical.............................................15 ms

Relay release time (at 20 °C)

Typical.............................................15 ms

Expected life

Mechanical (no load).......................5 × 10

operations

Electrical at maximum

operations

Caution

switching capacity ...........................10

Exceeding the maximum switching capability will decrease the expected life

of the NI 2590/2591.

PXI Bus Interface

Slave

NI 2590/2591 User Manual A-2 ni.com

PXI Trigger Bus

Power Requirement

Physical

Environment

Appendix A Specifications for NI 2590

Trigger lines ...........................................8

Star trigger.............................................. 1

+5 VDC

Minimum (all relays opened).......... 350 mA

Maximum (all relays closed) .......... 0.6 A

Dimensions............................................. 10 by 16 by 4 cm

(3.9by6.3by1.6in.)

Weight.................................................... 240 g (8.5 oz)

I/O connector.......................................... 5 SMB female

Operating temperature..........................0 to 50 °C

Storage temperature..............................–20 to 70 °C

Relative humidity................................... 5 to 85% noncondensing

Maximum altitude .................................. 2,000 m

Certifications and Compliances CE Mark Compliance

See the Declaration of Conformity sheet accompanying product.

Appendix A Specifications for NI 2591

NI 2591

Input Characteristics

Number of relays ....................................3

Common-mode voltage

Maximum switching voltage

Maximum switching capacity per channel

Maximum switching

power per channel...................................10 W

Contact on resistance (initial) .................200 mΩ max

Channel to earth...............................30 V

AC....................................................30 V

DC....................................................30 VDC

DC....................................................30 VDC at 0.33 ADC

AC....................................................30 V

or DC

rms

at 0.33 A

rms

Contact material......................................Gold

RF Performance Characteristics

Characteristic impedance (Z0) ................50 Ω

Insertion loss at:

< 2.5 GHz ........................................< 0.6 dB

< 4 GHz ...........................................< 0.9 dB

VSWR at:

< 2.5 GHz ........................................< 1.3

< 4 GHz ...........................................< 1.5

Isolation:

< 2.5 GHz ........................................< –60 dB

< 4 GHz ...........................................< –55 dB

Maximum RF carry power

at 900 MHz .............................................10 W

NI 2590/2591 User Manual A-4 ni.com

Note

Refer to the safety information in Chapter 2, NI 2590/2591 Operation, for important information about using your NI 2591 with high-power signals.

Dynamic Characteristics

Relay operate time (at 20 °C)

Typical ............................................ 15 ms

Relay release time (at 20 °C)

Typical ............................................ 15 ms

Expected life

Mechanical (no load) ...................... 5 × 10

Electrical at maximum

switching capacity........................... 10

Appendix A Specifications for NI 2591

operations

Caution

the NI 2591.

Exceeding the maximum switching capability will decrease the expected life of

Power Requirement

Physical

Environment

+5 VDC

Maximum (all relays closed) .......... 250 mW

Weight.................................................... 1.1 kg

Dimensions............................................. 10 by 16 by 4 cm

(3.9by6.3by1.6in.)

I/O connector.......................................... 5 SMA female per bank

Operating temperature..........................0 to 50 °C

Storage temperature..............................–20 to 70 °C

Relative humidity................................... 5 to 85% noncondensing

Appendix A Specifications for NI 2591

Electromagnetic compatibility

(EMC) emissions.............................Refer to the document supplied

EMI..................................................FCC Class A compliant

Maximum altitude...................................2,000 m

Certifications and Compliances CE Mark Compliance

See the Declaration of Conformity sheet accompanying product.

with the chassis for compliance to relevant directives.

NI 2590/2591 User Manual A-6 ni.com

Servicing Your Module

This appendix describes procedures for servicing your NI 2590/2591 module.

Replacing the NI 2590 Relay Module

The NI 2590 is constructed so that the relay module can be replaced when the relays fail. The life of the relay is nominally 10 switching the maximum rated load.

You can order an RF 2590 replacement relay module for your NI 2590 from National Instruments. The replacement kit contains the fully assembled module.

operations when

1 Header 2 Relay Module

3Screws 4 SMB Connectors

Figure B-1. NI 2590 Parts Locator Diagram

5 Hex Nuts and Washers

Appendix B Servicing Your Module

Follow these instructions to replace the failed module as shown in Figure B-1.

1. Ground yourself with a grounding strap or a ground connected to your PXI chassis. Properly grounding yourself prevents damage to your PXI module from electrostatic discharge.

2. Remove the two Phillips-head screws that fasten the NI 2590 relay module board to the module carrier.

3. Remove the hex nuts and washers from the SMB connectors on the front panel.

4. Gently disconnect the rear of the module from the header, then carefully remove the module.

5. Install the replacement module and screws in reverse order, taking care not to damage the connector pins on the module.

Replacing the NI 2591 Relay Module

The NI 2591 is constructed so that the relay module can be replaced when the relays fail. The life of the relay is nominally 10 switching the maximum rated load.

You can order an RF 2591 replacement relay module for your NI 2591 from National Instruments. The replacement kit contains the fully assembled module.

operations when

NI 2590/2591 User Manual B-2 ni.com

Appendix B Servicing Your Module

1 Hex Nuts and Washers 2 Relay Module 3 Base Card

Figure B-2.

RF 2591 Replacement Relay Module

Follow these instructions to replace the failed module as shown in Figure B-2.

1. Ground yourself with a grounding strap or a ground connected to your PXI chassis. Properly grounding yourself prevents damage to your PXI module from electrostatic discharge.

2. Remove the four Phillips-head screws and nuts that fasten the NI 2591 relay module to the module carrier.

3. Remove the hex nuts and washers from the SMA connectors on the front panel.

4. Remove the PXI ejector handle screw that secures the front panel.

5. Remove the module from the base card.

6. Install the replacement module and screws in reverse order, taking care not to damage the connector pins on the module.

Common Questions

This appendix addresses common questions you may have while using your NI 2590/2591 switch module.

What should I do if the software detects the module but the switches do not switch?

Verify that the switches do not switch. Close your application program and then launch the soft front panel as described in the Set up and Test document you received with your kit. The soft front panel shows the state of each relay on the module. Try closing and opening the switches.

Also be sure to check the return codes of the NI-Switch operation to ensure that there are no errors (negative value) or warnings (positive value). You can also use the NI-Spy utility to check for error codes.

Finally, verify that your code is correct. For reference, see the examples described in the NI-SWITCH Software User Manual. The NI-Switch driver also ships with several examples in source code. Compare your algorithm to those in the examples.

What should I do if scanning does not work?

First, ensure that you have configured the switch module and the instrument to match trigger lines. The output trigger of the instrument should connect to the trigger input of the switch module. In addition, the scanner advanced trigger of the switch module should be connected to the input trigger of the instrument.

If the switch module is used to initiate the scan, make sure the scope or arb is waiting for a trigger before enabling scanning on the switch module. This is the recommended method for hardware scanning.

If the scope or arb is used to initiate the scan, enable scanning on the switch module before configuring the scope or arb to start taking measurements.

Appendix C Common Questions

Do I need to program the switch module myself?

The NI 2590/2591 comes with the NI-Switch driver software, which exports the full functionality of the module. NI-Switch handles the complex issues of direct memory access, interrupts, and operating system interfacing.

NI 2590/2591 User Manual C-2 ni.com

Technical Support Resources

Web Support

National Instruments Web support is your first stop for help in solving installation, configuration, and application problems and questions. Online problem-solving and diagnostic resources include frequently asked questions, knowledge bases, product-specific troubleshooting wizards, manuals, drivers, software updates, and more. Web support is available through the Technical Support section of

NI Developer Zone

ni.com

The NI Developer Zone at building measurement and automation systems. At the NI Developer Zone, you can easily access the latest example programs, system configurators, tutorials, technical news, as well as a community of developers ready to share their own techniques.

Customer Education

National Instruments provides a number of alternatives to satisfy your training needs, from self-paced tutorials, videos, and interactive CDs to instructor-led hands-on courses at locations around the world. Visit the Customer Education section of syllabi, training centers, and class registration.

System Integration

If you have time constraints, limited in-house technical resources, or other dilemmas, you may prefer to employ consulting or system integration services. You can rely on the expertise available through our worldwide network of Alliance Program members. To find out more about our Alliance system integration solutions, visit the System Integration section of

ni.com

ni.com/zone

ni.com

is the essential resource for

for online course schedules,

Appendix D Technical Support Resources

Worldwide Support

National Instruments has offices located around the world to help address your support needs. You can access our branch office Web sites from the Worldwide Offices section of up-to-date contact information, support phone numbers, e-mail addresses, and current events.

If you have searched the technical support resources on our Web site and still cannot find the answers you need, contact your local office or National Instruments corporate. Phone numbers for our worldwide offices are listed at the front of this manual.

ni.com

. Branch office Web sites provide

NI 2590/2591 User Manual D-2 ni.com

Glossary

Prefix Meaning Value

p- pico- 10

n- nano- 10

µ- micro- 10

m- milli- 10

M- mega- 10

G- giga- 10

Numbers and Symbols

° degrees

Ω ohms

% percent

–12

–9

– 6

–3

> greater than

< less than

A amperes

AC alternating current

ADC amperes direct current

ANSI American National Standards Institute

Glossary

breakpoint a specified point in program code where the program pauses to perform

some action; a breakpoint interrupt can be added to a scan list for debugging or other special needs.

bus the group of conductors that interconnect individual circuitry in a computer.

Typically, a bus is the expansion vehicle to which I/O or other devices are connected. Examples of PC buses are the ISA and PCI bus.

CCelsius

channel pin or wire lead on the multiplexer to which you apply or from which you

read the signal

common a channel that is typically the output of a switch module

contact bounce the intermittent switching that occurs when the movable metal parts of a

relay make or break contact

DC direct current

debounced indicates when the contact bounce has ended. See contact bounce.

device a plug-in module, board, or pad that can contain multiple channels and

conversion devices. Some examples of devices are computers, multimeters, multiplexers, oscillators, operator interfaces, and counters.

diode an electronic component that acts primarily as a one-way valve

drivers/driver software software that controls a specific hardware device such as a switch module

external trigger a voltage pulse from an external source that triggers an event such as

A/D conversion

NI 2590/2591 User Manual G-2 ni.com

Glossary

flyback voltage the voltage spike generated the instant current stops flowing through an

inductor

handshaking the use of two trigger lines between two instruments, such as a switch and

a DMM, to synchronize their actions

Hz hertz—the number of scans read or updates written per second

in. inches

Interchangeable Virtual Instrument

I/O input/output—the transfer of data to/from a computer system involving

ISA Industry Standard Architecture

IVI See Interchangeable Virtual Instrument.

an advanced architecture for instrument drivers that includes features such as simulation and state caching

communications channels, operator interface devices, and/or data acquisition and control interfaces

NI-Switch an IVI-based instrument driver that supports the National Instruments line

of switch modules

PXI PCI with extensions for instrumentation

Glossary

random scanning scanning the channels in a mux in any order

reflective switch a switch architecture in which the unused channels are NOT terminated in

the characteristic impedance of the system. The unused channels are open circuits.

relay a switch that connects or disconnects the signal to a common through the

physical movement of a metal arm

rms root mean square—the square root of the average value of the square of the

instantaneous signal amplitude; a measure of signal amplitude

s seconds

scan the data acquisition of signals connected to multiple channels of a

multiplexer. Typically, the measurement device uses a trigger to advance the multiplexer to the next channel in the scan.

scan list a list of channels supplied to NI-Switch that indicates the order in which

channels will be scanned

scanner advanced trigger

SCC switch control circuitry

SMB sub-miniature snap-on connector

soft front panel a graphical program included with NI-Switch that you can use to

the trigger generated by the switch module when scanning. The trigger occurs after the switch module has closed a switch and the switch has settled.

interactively control the switch

trigger any event that causes or starts some form of data capture

TTL Transistor-Transistor Logic

NI 2590/2591 User Manual G-4 ni.com

Glossary

V volts

varistor an electrical resistor whose resistance depends on the applied voltage

VDC volts, direct current

VI virtual instrument—(1) a combination of hardware and/or software

elements, typically used with a PC, that has the functionality of a classic stand-alone instrument (2) a LabVIEW software module (VI), which consists of a front panel user interface and a block diagram program

VSWR Voltage Standing Wave Ratio. The impedance match of the device to the

overall system.

Wwatts

wire data path between nodes

Index

block diagrams

NI 2590, 2-3 NI 2591, 2-4

cables and accessories, 1-6 certification and compliances

NI 2590, A-3

NI 2591, A-6 CH<0..3> signal (table), 1-4 COM signal (table), 1-4 common questions about NI 2590/2591,

C-1toC-2

connectors

front connector

NI 2590 (figure), 1-3

NI 2591 (figure), 1-4 overview, 1-3 signal descriptions for front connectors

(table), 1-4 contact protection, 1-2 conventions used in manual, vi customer education, D-1

debouncing of switches, 1-1 dynamic characteristics

NI 2590, A-2 NI 2591, A-5

environment specifications

NI 2590, A-3 NI 2591, A-5 to A-6

external trigger input, 1-2, 2-7

front connector

NI 2590 front connector (figure), 1-3 NI 2591 front connector (figure), 1-4 signal descriptions (table), 1-4

input characteristics

NI 2590, A-1 NI 2591, A-4

LabVIEW and LabWindows/CVI software, 1-5

maintaining the NI 2590. See servicing the

NI 2590/2591.

multiboard triggering, 2-8 to 2-9

National Instruments application software, 1-5 NI 2590/2591 switch module. See also operation

of NI 2590/2591.

block diagrams, 2-3 to 2-4 cabling and accessories, 1-6 common questions, C-1 to C-2 connecting signals, 1-3

Index

contact protection, 1-2 front connectors (figures), 1-3 to 1-4 overview, 1-1 parts locator diagram

NI 2590, B-1

NI 2591, B-3

replacing relay module

NI 2590, B-1 to B-2

NI 2591, B-2 to B-3

RF switching precautions, 1-2 servicing,B-1toB-3 software choices, 1-5 to 1-6

triggers, 1-1 to 1-2 NI Developer Zone, D-1 NI-Switch instrument driver, 1-5, C-2

operation of NI 2590/2591, 2-1 to 2-9

block diagrams

NI 2590, 2-3

NI 2591, 2-4 functional overview, 2-2 PXI interface, 2-7 to 2-9

initiating scanning, 2-8

multiboard triggering, 2-8 to 2-9

PXI triggers, 2-7 to 2-8 random scanning, 2-6 to 2-7 relay operation

NI 2590, 2-5

NI 2591, 2-5 safety instructions, 2-1 switch control circuitry, 2-6

parts locator diagram

NI 2590, B-1 NI 2591, B-3

physical specifications

NI 2590, A-3 NI 2591, A-5

power requirement specifications

NI 2590, A-3 NI 2591, A-5

programming. See NI-Switch instrument

driver; software choices.

PXI interface, 2-7 to 2-9

bus interface specifications, A-2 initiating scanning, 2-8 multiboard triggering, 2-8 to 2-9

PXI triggers, 2-7 to 2-8

external trigger input, 1-2, 2-7 modes of operation, 2-8 overview, 1-1 scanner advanced, 1-1, 2-7 trigger bus specifications, A-3

questions about NI 2590/2591, C-1 to C-2

random scanning, 2-6 to 2-7 reflective switch, 1-2 relay module, replacing

NI 2590, B-1 to B-2 NI 2591, B-2 to B-3

relay operation

NI 2590, 2-5 NI 2591, 2-5

RF performance characteristics

NI 2590, A-1 to A-2 NI 2591, A-4 to A-5

RF switching precautions, 1-2

NI 2590/2591 User Manual I-2 ni.com

Index

safety instructions, 2-1 scanner advanced trigger

modes of operation, 2-8 overview, 1-1 purpose and use, 2-7

scanning

common questions, C-1 to C-2 initiating, 2-8 random scanning, 2-6 to 2-7

servicing the NI 2590/2591, B-1 to B-3

parts locator diagram

NI 2590, B-1 NI 2591, B-3

replacing relay module

NI 2590, B-1 to B-2 NI 2591, B-2 to B-3

signal descriptions for front connector

(table), 1-4

software choices, 1-5 to 1-6

National Instruments application

software, 1-5

NI-Switch instrument driver, 1-5 third-party software, 1-6

specifications, A-1 to A-6

certification and compliances

NI 2590, A-3 NI 2591, A-6

dynamic characteristics

NI 2590, A-2 NI 2591, A-5

environment

NI 2590, A-3 NI 2591, A-5 to A-6

input characteristics

NI 2590, A-1 NI 2591, A-4

physical

NI 2590, A-3 NI 2591, A-5

power requirement

NI 2590, A-3

NI 2591, A-5 PXI bus interface, A-2 PXI trigger bus, A-3 RF performance characteristics

NI 2590, A-1 to A-2 NI 2591, A-4 to A-5

switch control circuitry, 2-6 switches do not switch, C-1 system integration, by National

Instruments, D-1

technical support resources, D-1 to D-2 third-party software, 1-6 triggering, multiboard, 2-8 to 2-9 triggers. See PXI triggers.

Web support from National Instruments, D-1 Worldwide technical support, D-2

National Instruments NI 2590, NI 2591 User Manual

Specifications and Main Features

Frequently Asked Questions

User Manual

NI 2590/2591 User Manual

Worldwide Technical Support and Product Information

National Instruments Corporate Headquarters

Worldwide Offices

Important Information

Warranty

Copyright

Trademarks

WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS

Compliance

Conventions

Contents

Triggers

RF Switching Precautions

Contact Protection

Connecting Signals

NI 2590 Front Connector

Figure 1-1. NI 2590 Front Connector

NI 2591 Front Connector

Figure 1-2. NI 2591 Front Connector

Table 1-1. Front Connector Signal Description

Software Choices

National Instruments Application Software

Third-Party Software

Cabling and Accessory Requirements

Safety Instructions

Functional Overview

Figure 2-1. NI 2590 Module Block Diagram

Figure 2-2. NI 2591 Module Block Diagram

Relay Operation

Switch Control Circuitry

Random Scanning

PXI Interface

PXI Triggers

External Trigger Input

Scanner Advanced

Modes

Initiating Scanning

Multiboard Triggering

Figure B-1. NI 2590 Parts Locator Diagram

Glossary

Numbers and Symbols

Index