National Instruments T2111 User Manual

DAQCard E Series

User Manual

Multifunction I/O Cards for PCMCIA

June 1996 Edition

Part Number 321138A-01



Copyright 1996 National Instruments Corporation. All Rights Reserved.

This document was created with FrameMaker 4.0.4

Internet Support

GPIB:

[e-mail]

DAQ:

[e-mail]

VXI:

[e-mail]

LabVIEW:
LabWindows:
HiQ:
VISA:

[e-mail]

[e-mail]

[e-mail]

[e-mail]

E-mail:
FTP Site:
Web Address:

[e-mail]

ftp.natinst.com

http://www.natinst.com

Bulletin Board Support

BBS United States: [phone] or [phone]
BBS United Kingdom: 01635 551422
BBS France: 1 48 65 15 59

FaxBack Support

[phone]

Telephone Support (U.S.)

Tel: [phone]
Fax: [phone]

International Offices

Australia 03 9 879 9422, Austria 0662 45 79 90 0, Belgium 02 757 00 20,
Canada (Ontario) 519 622 9310, Canada (Québec) 514 694 8521, Denmark 45 76 26 00,
Finland 90 527 2321, France 1 48 14 24 24, Germany 089 741 31 30, Hong Kong 2645 3186,
Italy 02 413091, Japan 03 5472 2970, Korea 02 596 7456, Mexico 95 800 010 0793,
Netherlands 0348 433466, Norway 32 84 84 00, Singapore 2265886, Spain 91 640 0085,
Sweden 08 730 49 70, Switzerland 056 200 51 51, Taiwan 02 377 1200, U.K. 01635 523545

National Instruments Corporate Headquarters

6504 Bridge Point Parkway Austin, TX 78730-5039 Tel: [phone]

Important Information

Warranty

Copyright

Trademarks

The DAQCard E Series cards 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 manual 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

E

SPECIFICALLY DISCLAIMS ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE

C

USTOMER’S RIGHT TO RECOVER DAMAGES CAUSED BY FAULT OR NEGLIGENCE ON THE PART OF NATIONAL

I

NSTRUMENTS SHALL BE LIMITED TO THE AMOUNT THERETOFORE PAID BY THE CUSTOMER
WILL NOT BE LIABLE FOR DAMAGES RESULTING FROM LOSS OF DATA, PROFITS, USE OF PRODUCTS, OR INCIDENTAL OR
CONSEQUENTIAL DAMAGES, EVEN IF ADVISED OF THE POSSIBILITY THEREOF

Instruments will 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.

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.

LabVIEW, NI-DAQ, DAQCard, DAQPad, DAQ-STC, NI-PGIA, and SCXI are trademarks of National
Instruments Corporation.

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

, N

ATIONAL INSTRUMENTS MAKES NO WARRANTIES, EXPRESS OR IMPLIED, AND

. N

ATIONAL INSTRUMENTS

. This limitation of the liability of National

.

WARNING REGARDING MEDICAL AND CLINICAL USE OF NATIONAL INSTRUMENTS PRODUCTS

National Instruments products are not designed with components and testing intended to ensure a level of reliability
suitable for use in treatment and diagnosis of humans. Applications of National Instruments products involving
medical or clinical treatment can create a potential for accidental injury caused by product failure, or by errors on the
part of the user or application designer. Any use or application of National Instruments products for or involving
medical or clinical treatment must be performed by properly trained and qualified medical personnel, and all
traditional medical safeguards, equipment, and procedures that are appropriate in the particular situation to prevent
serious injury or death should always continue to be used when National Instruments products are being used.
National Instruments products are NOT intended to be a substitute for any form of established process, procedure, or
equipment used to monitor or safeguard human health and safety in medical or clinical treatment.

This document was created with FrameMaker 4.0.4

Table

of

Contents

About This Manual

Organization of This Manual ........................................................................................xi

Conventions Used in This Manual ................................................................................xii

National Instruments Documentation ...........................................................................xiii

Related Documentation .................................................................................................xiv

Customer Communication ............................................................................................xiv

Chapter 1
Introduction

About the DAQCard E Series .......................................................................................1-1

What You Need to Get Started ......................................................................................1-2

Software Programming Choices ...................................................................................1-2

LabVIEW and LabWindows/CVI Application Software ...............................1-2

NI-DAQ Driver Software ...............................................................................1-3

Register-Level Programming ..........................................................................1-4

Optional Equipment ......................................................................................................1-5

Custom Cabling .............................................................................................................1-5

Unpacking .....................................................................................................................1-6

Chapter 2
Installation and Configuration

Installation .....................................................................................................................2-1

Configuration ................................................................................................................2-2

Chapter 3
Hardware Overview

Analog Input ..................................................................................................................3-2

Input Mode ......................................................................................................3-2

Input Polarity and Input Range .......................................................................3-3

Considerations for Selecting Input Ranges ......................................3-6

Dither ..............................................................................................................3-6

Multichannel Scanning Considerations ..........................................................3-7

Analog Trigger ..............................................................................................................3-9

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Table of Contents

Digital I/O .....................................................................................................................3-12

Timing Signal Routing ..................................................................................................3-13

Programmable Function Inputs .......................................................................3-14

DAQCard Clocks ............................................................................................3-14

Chapter 4
Signal Connections

I/O Connector ................................................................................................................4-1

Analog Input Signal Connections .................................................................................4-10

Types of Signal Sources ................................................................................................4-12

Floating Signal Sources ..................................................................................4-12

Ground-Referenced Signal Sources ................................................................4-12

Input Configurations .....................................................................................................4-12

Differential Connection Considerations (DIFF Input Configuration) ............4-14

Single-Ended Connection Considerations ......................................................4-18

Common-Mode Signal Rejection Considerations ..........................................4-20

Digital I/O Signal Connections .....................................................................................4-21

Power Connections ........................................................................................................4-22

Timing Connections ......................................................................................................4-22

Programmable Function Input Connections ...................................................4-24

Data Acquisition Timing Connections ...........................................................4-24

General-Purpose Timing Signal Connections ................................................4-37

Differential Connections for Ground-Referenced

Signal Sources ................................................................................4-15

Differential Connections for Nonreferenced or Floating

Signal Sources ................................................................................4-16

Single-Ended Connections for Floating Signal Sources (RSE

Configuration) ................................................................................4-19

Single-Ended Connections for Grounded Signal Sources (NRSE

Configuration) ................................................................................4-19

SCANCLK Signal ............................................................................4-26

EXTSTROBE* Signal ......................................................................4-27

TRIG1 Signal ...................................................................................4-27

TRIG2 Signal ...................................................................................4-29

STARTSCAN Signal .......................................................................4-30

CONVERT* Signal ..........................................................................4-33

AIGATE Signal ................................................................................4-34

SISOURCE Signal ...........................................................................4-35

UISOURCE Signal ...........................................................................4-36

GPCTR0_SOURCE Signal ..............................................................4-37

GPCTR0_GATE Signal ...................................................................4-38

GPCTR0_OUT Signal ......................................................................4-38

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Field Wiring Considerations .........................................................................................4-44

Chapter 5
Calibration

Loading Calibration Constants ......................................................................................5-1

Self-Calibration .............................................................................................................5-2

External Calibration ......................................................................................................5-2

Other Considerations .....................................................................................................5-3

Appendix A
Specifications

DAQCard-AI-16E-4 ......................................................................................................A-1

DAQCard-AI-16XE-50 .................................................................................................A-8

Table of Contents

GPCTR0_UP_DOWN Signal ..........................................................4-39

GPCTR1_SOURCE Signal ..............................................................4-39

GPCTR1_GATE Signal ...................................................................4-40

GPCTR1_OUT Signal ......................................................................4-41

GPCTR1_UP_DOWN Signal ..........................................................4-42

FREQ_OUT Signal ..........................................................................4-43

Appendix B
Optional Cable Connector Descriptions

Appendix C
PC Card Questions and Answers

Appendix D
Common Questions

Appendix E
Power-Management Modes

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National Instruments Corporation vii DAQCard E Series User Manual

Table of Contents

Appendix F
Customer Communication

Glossary
Index

DAQCard E Series User Manual viii

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National Instruments Corporation

Figures

Figure 1-1. The Relationship between the Programming Environment, NI-DAQ,

Figure 2-1. A Typical Configuration for the DAQCard E Series Card ......................2-2

Figure 3-1. DAQCard-AI-16E-4 Block Diagram .......................................................3-1

Figure 3-2. DAQCard-AI-16XE-50 Block Diagram ..................................................3-2

Figure 3-3. Dither .......................................................................................................3-7

Figure 3-4. Analog Trigger Block Diagram ...............................................................3-9

Figure 3-5. Below-Low-Level Analog Triggering Mode ...........................................3-10

Figure 3-6. Above-High-Level Analog Triggering Mode ..........................................3-10

Figure 3-7. Inside-Region Analog Triggering Mode ..................................................3-11

Figure 3-8. High-Hysteresis Analog Triggering Mode ..............................................3-11

Figure 3-9. Low-Hysteresis Analog Triggering Mode ...............................................3-12

Figure 3-10. CONVERT* Signal Routing ....................................................................3-13

Figure 4-1. I/O Connector Pin Assignment for the DAQCard-AI-16E-4 and

Figure 4-2. DAQCard E Series PGIA .........................................................................4-11

Figure 4-3. Summary of Analog Input Connections ..................................................4-13

Figure 4-4. Differential Input Connections for Ground-Referenced Signals .............4-15

Figure 4-5. Differential Input Connections for Nonreferenced Signals .....................4-16

Figure 4-6. Single-Ended Input Connections for Nonreferenced or Floating Signals 4-19

Figure 4-7. Single-Ended Input Connections for Ground-Referenced Signals ..........4-20

Figure 4-8. Digital I/O Connections ...........................................................................4-21

Figure 4-9. Timing I/O Connections ..........................................................................4-23

Figure 4-10. Typical Posttriggered Acquisition ...........................................................4-25

Figure 4-11. Typical Pretriggered Acquisition .............................................................4-25

Figure 4-12. SCANCLK Signal Timing .......................................................................4-26

Figure 4-13. EXTSTROBE* Signal Timing ................................................................4-27

Figure 4-14. TRIG1 Input Signal Timing .....................................................................4-28

Figure 4-15. TRIG1 Output Signal Timing ..................................................................4-28

Figure 4-16. TRIG2 Input Signal Timing .....................................................................4-30

Figure 4-17. TRIG2 Output Signal Timing ..................................................................4-30

Figure 4-18. STARTSCAN Input Signal Timing .........................................................4-31

Figure 4-19. STARTSCAN Output Signal Timing ......................................................4-32

Figure 4-20. CONVERT* Input Signal Timing ...........................................................4-33

Figure 4-21. CONVERT* Output Signal Timing .........................................................4-34

Figure 4-22. SISOURCE Signal Timing ......................................................................4-35

Figure 4-23. UISOURCE Signal Timing ......................................................................4-36

Figure 4-24. GPCTR0_SOURCE Signal Timing .........................................................4-37

Figure 4-25. GPCTR0_GATE Signal Timing in Edge-Detection Mode .....................4-38

Table of Contents

and Your Hardware ................................................................................1-4

DAQCard-AI-16XE-50 ..........................................................................4-2

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National Instruments Corporation ix DAQCard E Series User Manual

Table of Contents

Figure 4-26. GPCTR0_OUT Signal Timing ................................................................4-39

Figure 4-27. GPCTR1_SOURCE Signal Timing .........................................................4-40

Figure 4-28. GPCTR1_GATE Signal Timing in Edge-Detection Mode .....................4-41

Figure 4-29. GPCTR1_OUT Signal Timing ................................................................4-41

Figure 4-30. GPCTR Timing Summary .......................................................................4-42

Figure B-1. 68-Pin AI Connector Pin Assignments ....................................................B-2

Figure B-2. 50-Pin AI Connector Pin Assignments ....................................................B-3

Tables

Table 3-1. Available Input Configurations for the DAQCard E Series ....................3-3

Table 3-2. Actual Range and Measurement Precision ..............................................3-4

Table 3-3. Actual Range and Measurement Precision, DAQCard-AI-16XE-50 ......3-5

Table 4-1. I/O Connector Signal Descriptions ..........................................................4-3

Table 4-2. I/O Signal Summary, DAQCard-AI-16E-4 .............................................4-5

Table 4-3. I/O Signal Summary, DAQCard-AI-16XE-50 ........................................4-8

Table E-1. DAQCard E Series Power-Management Modes ......................................E-2

DAQCard E Series User Manual x

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National Instruments Corporation

About

This

Manual

This manual describes the electrical and mechanical aspects of each
card in the DAQCard E Series product line and contains information
concerning their operation and programming. Unless otherwise noted,
text applies to all cards in the DAQCard E Series.

The DAQCard E Series includes the following cards:

• DAQCard-AI-16E-4

• DAQCard-AI-16XE-50

The DAQCard E Series cards are high-performance multifunction
analog, digital, and timing I/O cards for computers with PCMCIA slots
compliant with rev. 2.1 of the PCMCIA specifications. Supported
functions include analog input, analog output, digital I/O, and timing
I/O.

Organization of This Manual

The

DAQCard E Series User Manual

• Chapter 1,
lists what you need to get started, describes the optional software
and optional equipment, and explains how to unpack your
DAQCard E Series card.

• Chapter 2,
and configure your DAQCard E Series card.

• Chapter 3,
hardware functions on your DAQCard E Series card.

• Chapter 4, Signal Connections
output signal connections to your DAQCard E Series card via the
DAQCard I/O connector.

• Chapter 5,
your DAQCard E Series card.

• Appendix A,
DAQCard in the DAQCard E Series.



National Instruments Corporation xi DAQCard E Series User Manual

Introduction

Installation and Configuration

Hardware Overview

Calibration,

Specifications

, describes the DAQCard E Series cards,

discusses the calibration procedures for

is organized as follows:

, explains how to install

, presents an overview of the

, describes how to make input and

, lists the specifications for each

This document was created with FrameMaker 4.0.4

About This Manual

• Appendix B,
connectors on the optional cables for the DAQCard E Series cards.

• Appendix C,
common questions and answers relating to PC Card operation.

• Appendix D,
questions and their answers relating to usage and special features
of your DAQCard E Series card.

• Appendix E,
management modes of the DAQCard E Series cards.

• Appendix F,
to request help from National Instruments or to comment on our
products.

• The

• The

Glossary

used in this manual, including acronyms, abbreviations, metric
prefixes, mnemonics, and symbols.

Index

including the page where you can find the topic.

Optional Cable Connector Descriptions

PC Card Questions and Answers

Common Questions

Power-Management Modes

Customer Communication

contains an alphabetical list and description of terms

alphabetically lists topics covered in this manual,

Conventions Used in This Manual

The following conventions are used in this manual.

♦

< > Angle brackets containing numbers separated by an ellipsis represent a

bold

bold italic

italic

monospace

The ♦ indicates that the text following it applies only to specific

DAQCard E Series boards.

range of values associated with a bit, port, or signal name (for example,
ACH<0..7> stands for ACH0 through ACH7).

Bold text denotes parameters, menus, menu items, dialog box buttons

or options, and error messages.

Bold italic text denotes a note, caution, or warning.

Italic text denotes emphasis on a specific DAQCard in the
DAQCard E Series or on other important information, a cross reference,
or an introduction to a key concept.

Text in this font denotes text or characters that are to be literally input
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

, describes the

, contains a list of

, contains a list of commonly asked

, describes the power

, contains forms you can use

DAQCard E Series User Manual xii

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National Instruments Corporation

names, functions, operations, variables, filenames, and extensions, and
for statements and comments taken from program code.

NI-DAQ NI-DAQ refers to NI-DAQ software unless otherwise noted.
PC Card PC Card refers to a PCMCIA card.
SCXI SCXI stands for Signal Conditioning eXtensions for Instrumentation

and is a National Instruments product line designed to perform
front-end signal conditioning for National Instruments plug-in DAQ
boards.

Abbreviations, acronyms, metric prefixes, mnemonics, symbols, and
terms are listed in the

Glossary

at the end of this manual.

National Instruments Documentation

The

DAQCard E Series User Manual

set for your DAQ system. You could have any of several types of
manuals depending on the hardware and software in your system. Use
the manuals you have as follows:

•

Getting Started with SCXI

manual you should read. It gives an overview of the SCXI system
and contains the most commonly needed information for the
modules, chassis, and software.

• Your SCXI hardware user manuals—If you are using SCXI, read
these manuals next for detailed information about signal
connections and module configuration. They also explain in greater
detail how the module works and contain application hints.

• Your DAQ hardware user manuals—These manuals have detailed
information about the DAQ hardware that plugs into or is
connected to your computer. Use these manuals for hardware
installation and configuration instructions, specification
information about your DAQ hardware, and application hints.

• Software documentation—You might have several sets of software
documentation, including LabVIEW, LabWindows/CVI, and
NI-DAQ. After you have set up your hardware system, use either
the application software (LabVIEW or LabWindows/CVI) or the
NI-DAQ documentation to help you write your application. If you
have a large and complicated system, it is worthwhile to look
through the software documentation before you configure your
hardware.

is one piece of the documentation

—If you are using SCXI, this is the first

About This Manual



National Instruments Corporation xiii DAQCard E Series User Manual

About This Manual

• Accessory installation guides or manuals—If you are using
accessory products, read the terminal block and cable assembly
installation guides. They explain how to physically connect the
relevant pieces of the system. Consult these guides when you are
making your connections.

• SCXI chassis manuals—If you are using SCXI, read these manuals
for maintenance information on the chassis and installation
instructions.

Related Documentation

The following National Instruments document contains information

you may find helpful:

• DAQCard E Series Register-Level Programmer Manual

This manual is available by request. If you are using NI-DAQ,
LabVIEW, or LabWindows/CVI, you should not need the register-level
programming manual.

Customer Communication

National Instruments wants to receive your comments on our products
and manuals. We are interested in the applications you develop with our
products, and we want to help if you have problems with them. To make
it easy for you to contact us, this manual contains comment and
configuration forms for you to complete. These forms are in

Appendix F,

DAQCard E Series User Manual xiv

Customer Communication

, at the end of this manual.

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National Instruments Corporation

Chapter

Introduction

This chapter describes the DAQCard E Series cards, lists what you need
to get started, describes the optional software and optional equipment,
and explains how to unpack your DAQCard E Series card.

About the DAQCard E Series

Thank you for buying a National Instruments DAQCard E Series card.
The DAQCard E Series cards are multifunction analog, digital, and
timing I/O cards for computers equipped with Type II PCMCIA slots.
This family of cards features 12-bit and 16-bit ADCs with eight lines of
TTL-compatible digital I/O, and two 24-bit counter/timers for timing
I/O.

The DAQCard E Series cards use the National Instruments DAQ-STC
system timing controller for time-related functions. The DAQ-STC
consists of three timing groups that control analog input, analog output,
and general-purpose counter/timer functions. These groups include a
total of seven 24-bit and three 16-bit counters and a maximum timing
resolution of 50 ns.

1

The DAQCard E Series cards can interface to an SCXI system so that
you can acquire over 3,000 analog signals from thermocouples, RTDs,
strain gauges, voltage sources, and current sources. You can also
acquire or generate digital signals for communication and control. SCXI
is the instrumentation front end for plug-in DAQ boards.

Detailed specifications for the DAQCard E Series cards are in
Appendix A,

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National Instruments Corporation 1-1 DAQCard E Series User Manual

This document was created with FrameMaker 4.0.4

Specifications

.

Chapter 1 Introduction

What You Need to Get Started

To set up and use your DAQCard E Series card, you will need the
following:

❏

One of the following cards:

DAQCard-AI-16E-4
DAQCard-AI-16XE-50

❏

DAQCard E Series User Manual

❏

One of the following software packages and documentation

NI-DAQ for PC compatibles
LabVIEW for PC compatibles
LabWindows/CVI

❏

Your computer

Software Programming Choices

There are several options to choose from when programming your
National Instruments DAQ and SCXI hardware. You can use
LabVIEW, LabWindows/CVI, NI-DAQ, or register-level
programming.

LabVIEW and LabWindows/CVI 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.

LabVIEW features interactive graphics, a state-of-the-art user
interface, and a powerful graphical programming language. The
LabVIEW Data Acquisition VI Library, a series of VIs for using
LabVIEW with National Instruments DAQ hardware, is included with
LabVIEW. The LabVIEW Data Acquisition VI Library is functionally
equivalent to the NI-DAQ software.

LabWindows/CVI features interactive graphics, a state-of-the-art user
interface, and uses the ANSI standard C programming language. The

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National Instruments Corporation

LabWindows/CVI Data Acquisition Library, a series of functions for
using LabWindows/CVI with National Instruments DAQ hardware, is
included with the NI-DAQ software kit. The LabWindows/CVI Data
Acquisition Library is functionally equivalent to the NI-DAQ software.

Using LabVIEW or LabWindows/CVI software will greatly reduce the
development time for your data acquisition and control application.

NI-DAQ Driver Software

The NI-DAQ driver software is included at no charge with all National
Instruments DAQ hardware. NI-DAQ is not packaged with signal
conditioning or accessory products. NI-DAQ has an extensive library of
functions that you can call from your application programming
environment. These functions include routines for analog input (A/D
conversion), buffered data acquisition (high-speed A/D conversion),
analog output (D/A conversion), waveform generation (timed D/A
conversion), digital I/O, counter/timer operations, SCXI, RTSI,
calibration, messaging, and acquiring data to extended memory.

NI-DAQ has both high-level DAQ I/O functions for maximum ease of
use and low-level DAQ I/O functions for maximum flexibility and
performance. Examples of high-level functions are streaming data to
disk or acquiring a certain number of data points. An example of a
low-level function is writing directly to registers on the DAQ device.
NI-DAQ does not sacrifice the performance of National Instruments
DAQ devices because it lets multiple devices operate at their peak
performance.

Chapter 1 Introduction

NI-DAQ also internally addresses many of the complex issues between
the computer and the DAQ hardware such as programming interrupts
and DMA controllers. NI-DAQ maintains a consistent software
interface among its different versions so that you can change platforms
with minimal modifications to your code. Whether you are using
conventional programming languages, LabVIEW, or

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National Instruments Corporation 1-3 DAQCard E Series User Manual

Chapter 1 Introduction

LabWindows/CVI, your application uses the NI-DAQ driver software,
as illustrated in Figure 1-1.

Conventional 

Programming 

Environment 

(PC, Macintosh, or 

Sun SPARCstation)

Figure 1-1.



SCXI Hardware

The Relationship between the Programming Environment, NI-DAQ,

LabVIEW 

(PC, Macintosh, or 

Sun SPARCstation)

NI-DAQ

Driver Software

DAQ or 

LabWindows/CVI

(PC or 

Sun SPARCstation)

Personal 
Computer

or

Workstation





and Your Hardware

You can use your DAQCard E Series card, together with other PC, AT,
EISA, DAQCard, and DAQPad Series DAQ and SCXI hardware, with
NI-DAQ software.

Register-Level Programming

The final option for programming any National Instruments DAQ
hardware is to write register-level software. Writing register-level
programming software can be very time-consuming and inefficient and
is not recommended for most users.

Even if you are an experienced register-level programmer, consider
using NI-DAQ, LabVIEW, or LabWindows/CVI to program your
National Instruments DAQ hardware. Using the NI-DAQ, LabVIEW, or
LabWindows/CVI software is as easy and as flexible as register-level
programming and can save weeks of development time.

DAQCard E Series User Manual 1-4

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National Instruments Corporation

Optional Equipment

National Instruments offers a variety of products to use with your
DAQCard E Series card, including cables, connector blocks, and other
accessories, as follows:

• Cables and cable assemblies, shielded and ribbon

• Connector blocks, shielded and unshielded, with 50 and 68-pin
screw terminals

• SCXI modules and accessories for isolating, amplifying, exciting,
and multiplexing signals for relays and analog output. With SCXI
you can condition and acquire up to 3072 channels.

• Low channel-count signal conditioning modules, cards, and
accessories, including conditioning for strain gauges and RTDs,
simultaneous sample-and-hold circuitry, and relays

For more specific information about these products, refer to your

National Instruments catalogue or call the office nearest you.

Custom Cabling

Chapter 1 Introduction

National Instruments offers cables and accessories for you to prototype
your application or to use if you frequently change DAQCard
interconnections.

If you want to develop your own cable, however, the following
guidelines may be useful:

• For the analog input signals, shielded twisted-pair wires for each
analog input pair yield the best results, assuming that you use
differential inputs. Tie the shield for each signal pair to the ground
reference at the source.

• You should route the analog lines separately from the digital lines.

• When using a cable shield, use separate shields for the analog and
digital halves of the cable. Failure to do so results in noise coupling
into the analog signals from transient digital signals.

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National Instruments Corporation 1-5 DAQCard E Series User Manual

Chapter 1 Introduction

Unpacking

The following list gives recommended National Instruments cable

assemblies that mate to your DAQCard I/O connector.

♦

DAQCard-AI-16E-4

PSHR68-68M, a shielded 68-position ribbon cable, with male-to­male connectors. This connects to an SH6868 or SH6850 shielded
cable.

PR68-68F, an unshielded 68-position ribbon cable

♦

DAQCard-AI-16XE-50

PSHR68-68M, a shielded 68-position ribbon cable, with male-to­male connectors. This connects to an SH6868 or SH6850 shielded
cable.

PR68-68F, an unshielded 68-position ribbon cable

Your DAQCard E Series card is shipped in an antistatic vinyl box.
When you are not using your DAQCard, store it in this box. Because
your DAQCard is enclosed in a fully shielded case, no additional
electrostatic precautions are necessary. However, for your own safety
and to protect your DAQCard, never attempt to touch the connector
pins.

DAQCard E Series User Manual 1-6



National Instruments Corporation

Chapter

Installation and
Configuration

This chapter explains how to install and configure a DAQCard E Series
card.

Installation

Note:

You should install your driver software before installing your hardware.
Refer to your NI-DAQ release notes for software installation instructions.

There are two basic steps to installing a DAQCard E Series card.

1. If you have Windows 3.1, you must have Card & Socket

2. Insert the DAQCard and attach the I/O cable.

2

Services 2.0 (or a later version) software installed on your
computer. If you have Windows 95, you do not need Card & Socket
Services. This device is built-in to the Windows 95 operating
system.

The DAQCard has two connectors—a 68-pin PCMCIA bus
connector on one end and a 68-pin I/O connector on the other end.
Insert the PCMCIA bus connector into any available Type II
PCMCIA slot until the connector is seated firmly. Notice that the
DAQCard and I/O cable are both keyed so that the cable can be
inserted only one way.

Be careful not to put strain on the I/O cable when inserting it into
and removing it from the DAQCard. Always grasp the cable by the
connector you are plugging or unplugging.
the I/O cable to unplug it from the DAQCard.

Your DAQCard can be connected to 68- and 50-pin accessories.
You can use either a 68-pin female cable to plug into the
PSHR68-68M with your DAQCard, or a 50-pin male cable and the
PSHR68-68M and SH6850 with your DAQCard. See Appendix B,

Optional Cable Connector Descriptions

Never

pull directly on

, for more information.

The DAQCard is now installed. You are ready to make the appropriate
connections to the I/O connector cable as described in Chapter 4,

Connections



National Instruments Corporation 2-1 DAQCard E Series User Manual

This document was created with FrameMaker 4.0.4

.

Signal

Chapter 2 Installation and Configuration

Figure 2-1 shows an example of a typical configuration.

Portable

Computer

DAQCard

INSERT CARD

™

-AI-16E-4

PCMCIA Socket

PSHR68-68M

The Software is the Instrument

INSTRUMENTS

NATIONAL 

®

™

I/O Cable

Figure 2-1.

A Typical Configuration for the DAQCard E Series Card

Configuration

Your DAQCard is completely software-configurable. Refer to your
software documentation to install and configure your software.

If you are using NI-DAQ, refer to your NI-DAQ release notes to install
your driver software. Find the installation section for your operating
system and follow the instructions given there.

If you are using LabVIEW, refer to your LabVIEW release notes to
install your application software. After you have installed LabVIEW,

DAQCard E Series User Manual 2-2

SH6868 Cable

I/O Signals



National Instruments Corporation

Chapter 2 Installation and Configuration

refer to the NI-DAQ release notes and follow the instructions given
there for your operating system and LabVIEW.

If you are using LabWindows/CVI, refer to your LabWindows/CVI
release notes to install your application software. After you have
installed LabWindows/CVI, refer to the NI-DAQ release notes and
follow the instructions given there for your operating system and
LabWindows/CVI.



National Instruments Corporation 2-3 DAQCard E Series User Manual

Chapter

Hardware Overview

This chapter presents an overview of the hardware functions on your

DAQCard E Series card.

Figure 3-1 shows the block diagram for the DAQCard-AI-16E-4.

(8)

Analog

(8)

Muxes

Trigger Level

DACs

I/O Connector

Trigger

Voltage

REF

Calibration

Mux

2

Mux Mode
Selection
Switches

Circuitry

PFI / Trigger

Timing

Digital I/O (8)

Analog
Trigger

Dither

Circuitry

Calibration

DACs

3

+

NI-PGIA
Gain
Amplifier
–

Trigger

Counter/

Timing I/O

Digital I/O

Converter

Configuration

Memory

Analog Input

Timing/Control

DAQ - STC

Analog Output

Timing/Control

12-Bit

Sampling

A/D

AI Control

DMA/
Interrupt
Request

Bus

Interface

RTSI Bus

Interface

ADC

FIFO

Data (16)

IRQ
DMA

DAQ-STC

Interface

Analog

Input

Control

Bus

Data

Transceivers

EEPROM

EEPROM

Control

DAQ-PCMCIA

Analog
Output

Control

3

DMA

Interface

Bus

Interface

PCMCIA Connector

Figure 3-1.



National Instruments Corporation 3-1 DAQCard E Series User Manual

DAQCard-AI-16E-4 Block Diagram

This document was created with FrameMaker 4.0.4

Chapter 3 Hardware Overview

Figure 3-2 shows a block diagram for the DAQCard-AI-16XE-50.

Voltage

REF

(8)

Analog

(8)

Muxes

Calibration

Mux

I/O Connector

PFI / Trigger

Digital I/O (8)

Analog Input

Calibration

Timing

Mux Mode
Selection
Switches

DACs

3

+

Programmable
Gain
Amplifier
–

Figure 3-2.

Trigger

Counter/

Timing I/O

Digital I/O

DAQCard-AI-16XE-50 Block Diagram

Sampling

Converter

Configuration

Memory

Analog Input

Timing/Control

DAQ - STC

Analog Output
Timing/Control

16-Bit

A/D

2

FIFO

AI Control

DMA/
Interrupt
Request

Bus

Interface

RTSI Bus

Interface

ADC

Data (16)

IRQ

DMA

DAQ-STC

Analog

Input

Control

Bus

Interface

EEPROM

EEPROM

Control

DAQ-PCMCIA

Analog
Output
Control

Data

Transceivers

DMA

Interface

Bus

Interface

The analog input section of each DAQCard is software configurable.
You can select different analog input configurations through
application software designed to control the DAQCards. The following
sections describe in detail each of the analog input categories.

PCMCIA Connector

Input Mode

The DAQCards have three different input modes—nonreferenced
single-ended (NRSE) input, referenced single-ended (RSE) input, and
differential (DIFF) input. The single-ended input configurations use up
to 16 channels. The DIFF input configuration uses up to eight channels.
Input modes are programmed on a per channel basis for multimode
scanning. For example, you can configure the circuitry to scan 12
channels—four differentially configured channels and eight

DAQCard E Series User Manual 3-2



National Instruments Corporation

Chapter 3 Hardware Overview

single-ended channels. Table 3-1 describes the three input
configurations.

Table 3-1.

Available Input Configurations for the DAQCard E Series

Description

Configuration

DIFF

A channel configured in DIFF mode uses two analog
channel input lines. One line connects to the positive
input of the DAQCard programmable gain
instrumentation amplifier (PGIA), and the other
connects to the negative input of the PGIA.

RSE A channel configured in RSE mode uses one analog

channel input line, which connects to the positive
input of the PGIA. The negative input of the PGIA is
internally tied to analog input ground (AIGND).

NRSE A channel configured in NRSE mode uses one

analog channel input line, which connects to the
positive input of the PGIA. The negative input of the
PGIA connects to the analog input sense (AISENSE)
input.

For more information about the three types of input configuration, refer
to the

Analog Input Signal Connections

Connections

, which contains diagrams showing the signal paths for the

section in Chapter 4,

Signal

three configurations.

Input Polarity and Input Range

♦

DAQCard-AI-16E-4

This DAQCard has two input polarities—unipolar and bipolar.
Unipolar input means that the input voltage range is between 0 and
V

, where V

ref

that the input voltage range is between -V
DAQCard-AI-16E-4 has a unipolar input range of 10 V (0 to 10 V)
and a bipolar input range of 10 V (±5 V). You can program polarity
and range settings on a per channel basis so that you can configure
each input channel uniquely.



National Instruments Corporation 3-3 DAQCard E Series User Manual

is a positive reference voltage. Bipolar input means

ref

ref

/2

and +V

/2. The

ref

Chapter 3 Hardware Overview

The software-programmable gain on these cards increases their
overall flexibility by matching the input signal ranges to those that
the ADC can accommodate. The DAQCard-AI-16E-4 has gains of

0.5, 1, 2, 5, 10, 20, 50, and 100 and is suited for a wide variety of
signal levels. With the proper gain setting, you can use the ADC’s
full resolution to measure the input signal. Table 3-2 shows the
overall input range and precision according to the range
configuration and gain used.

Table 3-2.

Range

Actual Range and Measurement Precision

Gain Actual Input Range Resolution

Configuration

0 to +10 V

1.0

2.0

5.0

10.0

20.0

50.0

100.0

-5 to +5 V 0.5

1.0

2.0

5.0

10.0

20.0

50.0

100.0

1

The value of 1 LSB of the 12-bit ADC; that is, the voltage

0 to +10 V

0 to +5 V
0 to +2 V

0 to +1 V
0 to +500 mV
0 to +200 mV
0 to +100 mV

-10 to +10 V

-5 to +5 V

-2.5 to +2.5 V

-1 to +1 V

-500 to +500 mV

-250 to +250 mV

-100 to +100 mV

-50 to +50 mV

2.44 mV

1.22 mV

488.28 µV

244.14 µV

122.07 µV

48.83 µV

24.41 µV

4.88 mV

2.44 mV

1.22 mV

488.28 µV

244.14 µV

122.07 µV

48.83 µV

24.41 µV

increment corresponding to a change of one count in the ADC
12-bit count.

1

Note:

See Appendix A

ratings

.

♦

DAQCard-AI-16XE-50

This DAQCard has two input polarities—unipolar and bipolar.
Unipolar input means that the input voltage range is between 0 and
V

where V

,

ref

is a positive reference voltage. Bipolar input means

ref

that the input voltage range is between -V

DAQCard E Series User Manual 3-4

, Specifications,

for absolute maximum

and +V

ref



National Instruments Corporation

ref

. The

Chapter 3 Hardware Overview

DAQCard-AI-16XE-50 has a unipolar input range of 10 V
(0 to 10 V) and a bipolar input range of 20 V (±10 V). You can
program polarity and range settings on a per channel basis so that
you can configure each input channel uniquely.

Note:

You can calibrate your DAQCard-AI-16XE-50 analog input circuitry for
either a unipolar or bipolar polarity. If you mix unipolar and bipolar
channels in your scan list and you are using NI-DAQ, then NI-DAQ will
load the calibration constants appropriate to the polarity for which analog
input channel 0 is configured.

The software-programmable gain on these cards increases their
overall flexibility by matching the input signal ranges to those that
the ADC can accommodate. The DAQCard-AI-16XE-50 has gains
of 1, 2, 10, and 100 and is suited for a wide variety of signal levels.
With the proper gain setting, you can use the ADC’s full resolution
to measure the input signal. Table 3-3 shows the overall input range
and precision according to the range configuration and gain used.

Table 3-3.

Actual Range and Measurement Precision, DAQCard-AI-16XE-50

Range

Gain Actual Input Range Precision

1

Configuration

0 to +10 V

-10 to +10 V 1.0

1.0

2.0

10.0

100.0

2.0

10.0

100.0

0 to +10 V

0 to +5 V

0 to +1 V

0 to 100 mV

-10 to +10 V

-5 to +5 V

-1 to +1 V

-100 to +100 mV

152.59 µV

76.29 µV

15.26 µV

1.53 µV

305.18 µV

152.59 µV

30.52 µV

3.05 µV

1

The value of 1 LSB of the 16-bit ADC; that is, the voltage
increment corresponding to a change of one count in the ADC
16-bit count.

Note:

See Appendix A

ratings

.



National Instruments Corporation 3-5 DAQCard E Series User Manual

, Specifications,

for absolute maximum

Chapter 3 Hardware Overview

Dither

Considerations for Selecting Input Ranges

Which input polarity and range you select depends on the expected
range of the incoming signal. A large input range can accommodate a
large signal variation but reduces the voltage resolution. Choosing a
smaller input range improves the voltage resolution but may result in
the input signal going out of range. For best results, you should match
the input range as closely as possible to the expected range of the input
signal. For example, if you are certain the input signal will not be
negative (below 0 V), unipolar input polarity is best. However, if the
signal is negative or equal to zero, inaccurate readings will occur if you
use unipolar input polarity.

When you enable dither, you add approximately 0.5 LSB rms of white
Gaussian noise to the signal to be converted by the ADC. This addition
is useful for applications involving averaging to increase the resolution
of your DAQCard, as in calibration or spectral analysis. In such
applications, noise modulation is decreased and differential linearity is
improved by the addition of dither. When taking DC measurements,
such as when checking the DAQCard calibration, you should enable
dither and average about 1,000 points to take a single reading. This
process removes the effects of quantization and reduces measurement
noise, resulting in improved resolution. For high-speed applications not
involving averaging or spectral analysis, you may want to disable the
dither to reduce noise. You enable and disable the dither circuitry
through software.

Figure 3-3 illustrates the effect of dither on signal acquisition.
Figure 3-3a shows a small (±4 LSB) sine wave acquired with dither off.
The quantization of the ADC is clearly visible. Figure 3-3b shows what
happens when 50 such acquisitions are averaged together; quantization
is still plainly visible. In Figure 3-3c, the sine wave is acquired with
dither on. There is a considerable amount of noise visible. But
averaging about 50 such acquisitions, as shown in Figure 3-3d,
eliminates both the added noise and the effects of quantization. Dither
has the effect of forcing quantization noise to become a zero-mean
random variable rather than a deterministic function of the input signal.

DAQCard E Series User Manual 3-6



National Instruments Corporation

Chapter 3 Hardware Overview

LSBs

LSBs

6.0

6.0

4.0

4.0

2.0

2.0

0.0

0.0

-2.0

-2.0

-4.0

-4.0

-6.0

-6.0
100 200 300 4000 500

100 200 300 4000 500

LSBs

LSBs

6.0

6.0

4.0

4.0

2.0

2.0

0.0

0.0

-2.0

-2.0

-4.0

-4.0

-6.0

-6.0
100 200 300 4000 500

100 200 300 4000 500

a. Dither disabled; no averaging b. Dither disabled; average of 50 acquisitions

LSBs

LSBs

LSBs

6.0

6.0

4.0

4.0

2.0

2.0

0.0

0.0

-2.0

-2.0

-4.0

-4.0

-6.0

-6.0
100 200 300 4000 500

100 200 300 4000 500

c. Dither enabled; no averaging

LSBs

6.0

6.0

4.0

4.0

2.0

2.0

0.0

0.0

-2.0

-2.0

-4.0

-4.0

-6.0

-6.0
100 200 300 4000 500

100 200 300 4000 500

d. Dither enabled; average of 50 acquisitions

Figure 3-3.

Dither

You cannot disable dither on the DAQCard-AI-16XE-50. This is
because the ADC resolution is so fine that the ADC and the PGIA
inherently produce more than 0.5 LSB rms of noise. This is equivalent
to having a dither circuit that is always enabled.

Multichannel Scanning Considerations

All of the DAQCard E Series cards can scan multiple channels at the
same maximum rate as their single-channel rate; however, pay careful
attention to the settling times for each of the DAQCards. The settling
time for most of the DAQCards is independent of the selected gain,
even at the maximum sampling rate. The settling time for the high
channel count and very high-speed cards is gain dependent, which can
affect the useful sampling rate for a given gain. No extra settling time
is necessary between channels as long as the gain is constant and source



National Instruments Corporation 3-7 DAQCard E Series User Manual

Chapter 3 Hardware Overview

impedances are low. Refer to Appendix A,

Specifications

, for a

complete listing of settling times for each of the DAQCards.
When scanning among channels at various gains, the settling times may

increase. When the PGIA switches to a higher gain, the signal on the
previous channel may be well outside the new, smaller range. For
instance, suppose a 4 V signal is connected to channel 0 and a 1 mV
signal is connected to channel 1, and suppose the PGIA is programmed
to apply a gain of one to channel 0 and a gain of 100 to channel 1. When
the multiplexer switches to channel 1 and the PGIA switches to a gain
of 100, the new full-scale range is 100 mV (if the ADC is in unipolar
mode).

The approximately 4 V step from 4 V to 1 mV is 4,000% of the new
full-scale range. For a 12-bit DAQCard to settle within 0.012%
(120 ppm or 1/2 LSB) of the 100 mV full-scale range on channel 1, the
input circuitry has to settle to within 0.0003% (3 ppm or 1/80 LSB) of
the 4 V step. It may take as long as 100 µs for the circuitry to settle this
much. For a 16-bit DAQCard to settle within 0.0015% (15 ppm or
1 LSB) of the 100 mV full-scale range on channel 1, the input circuitry
has to settle within 0.00004% (0.4 ppm or 1/400 LSB) of the 4 V step.
It may take as long as 200 µs for the circuitry to settle this much. In
general, this extra settling time is not needed when the PGIA is
switching to a lower gain.

Settling times can also increase when scanning high-impedance signals
due to a phenomenon called
multiplexer injects a small amount of charge into each signal source
when that source is selected. If the source impedance is not low enough,
the effect of the charge—a voltage error—will not have decayed by the
time the ADC samples the signal. For this reason, you should keep
source impedances under 1 kΩ to perform high-speed scanning.

Due to problems with settling times, multichannel scanning is not
recommended unless sampling rates are low enough or it is necessary
to sample several signals as nearly simultaneously as possible. The data
is much more accurate and channel-to-channel independent if you
acquire data from each channel independently (for example, 100 points
from channel 0, then 100 points from channel 1, then 100 points from
channel 2, and so on).

DAQCard E Series User Manual 3-8

charge injection

, where the analog input



National Instruments Corporation

Chapter 3 Hardware Overview

Analog Trigger

Analog 
Input 
Channels

PFI0/TRIG1

♦

DAQCard-AI-16E-4

In addition to supporting internal software triggering and external
digital triggering to initiate a data acquisition sequence, the
DAQCard-AI-16E-4 also supports analog triggering. You can
configure the analog trigger circuitry to accept either a direct
analog input from the PFI0/TRIG1 pin on the I/O connector or a
postgain signal from the output of the PGIA, as shown in
Figure 3-4. The trigger-level range for the direct analog channel is

±

10 V in 78 mV steps. The range for the post-PGIA trigger
selection is simply the full-scale range of the selected channel, and
the resolution is that range divided by 256.

+

PGIA

-

Mux

ADC

Analog
Trigger
Circuit

DAQ-STC

Figure 3-4.

Analog Trigger Block Diagram

There are five analog triggering modes available, as shown in
Figures 3-5 through 3-9. You can set

lowValue

and

highValue

independently in software.



National Instruments Corporation 3-9 DAQCard E Series User Manual

Chapter 3 Hardware Overview

In below-low-level analog triggering mode, the trigger is generated
when the signal value is less than

lowValue

Trigger

lowValue. HighValue

is unused.

Figure 3-5.

Below-Low-Level Analog Triggering Mode

In above-high-level analog triggering mode, the trigger is
generated when the signal value is greater than

LowValue

is unused.

highValue

Trigger

Figure 3-6.

Above-High-Level Analog Triggering Mode

highValue

.

DAQCard E Series User Manual 3-10



National Instruments Corporation

Chapter 3 Hardware Overview

In inside-region analog triggering mode, the trigger is generated
when the signal value is between the

highValue

lowValue

Trigger

lowValue

and the

highValue

.

Figure 3-7.

Inside-Region Analog Triggering Mode

In high-hysteresis analog triggering mode, the trigger is generated
when the signal value is greater than
specified by

highValue

lowValue

lowValue

Trigger

Figure 3-8.

.

High-Hysteresis Analog Triggering Mode

highValue

, with the hysteresis



National Instruments Corporation 3-11 DAQCard E Series User Manual

Chapter 3 Hardware Overview

In low-hysteresis analog triggering mode, the trigger is generated
when the signal value is less than
specified by

highValue

lowValue

highValue.

Trigger

Figure 3-9. Low-Hysteresis Analog Triggering Mode

lowValue

, with the hysteresis

The analog trigger circuit generates an internal digital trigger based
on the analog input signal and the user-defined trigger levels. This
digital trigger can be used by any of the timing sections of the
DAQ-STC, including the analog input, analog output, and
general-purpose counter/timer sections. For example, the analog
input section can be configured to acquire n scans after the analog
input signal crosses a specific threshold. As another example, the
analog output section can be configured to update its outputs
whenever the analog input signal crosses a specific threshold.

Digital I/O

The DAQCard E Series cards contain eight lines of digital I/O for
general-purpose use. You can individually configure each line through
software for either input or output. At system startup and reset, the
digital I/O ports are all high impedance.

The hardware up/down control for general-purpose counters 0 and 1 are
connected onboard to DIO6 and DIO7, respectively. Thus, you can use
DIO6 and DIO7 to control the general-purpose counters. The up/down
control signals are input only and do not affect the operation of the DIO
lines.

DAQCard E Series User Manual 3-12



National Instruments Corporation

Timing Signal Routing

The DAQ-STC provides a very flexible interface for connecting timing
signals to other boards or external circuitry. Your DAQCard uses the
Programmable Function Input (PFI) pins on the I/O connector to
connect to external circuitry. These connections are designed to enable
the DAQCard to both control and be controlled by other boards and
circuits.

The DAQ-STC has a total of 13 internal timing signals that can be
controlled by an external source. These timing signals can also be
controlled by signals generated internally to the DAQ-STC, and these
selections are fully software configurable. For example, the signal
routing multiplexer for controlling the CONVERT* signal is shown in
Figure 3-10.

Chapter 3 Hardware Overview

PFI<0..9>

CONVERT*

Sample Interval Counter TC

GPCTR0_OUT

Figure 3-10. CONVERT* Signal Routing

This figure shows that CONVERT* can be generated from a number of
sources, including the external signals PFI<0..9> and the internal
signals Sample Interval Counter TC and GPCTR0_OUT.



National Instruments Corporation 3-13 DAQCard E Series User Manual

Chapter 3 Hardware Overview

Programmable Function Inputs

The 10 PFIs are connected to the signal routing multiplexer for each
timing signal, and software can select one of the PFIs as the external
source for a given timing signal. It is important to note that any of the
PFIs can be used as an input by any of the timing signals and that
multiple timing signals can use the same PFI simultaneously. This
flexible routing scheme reduces the need to change physical
connections to the I/O connector for different applications.

You can also individually enable each of the PFI pins to output a
specific internal timing signal. For example, if you need the UPDATE*
signal as an output on the I/O connector, software can turn on the output
driver for the PFI5/UPDATE* pin.

DAQCard Clocks

Many functions performed by the DAQCard E Series cards require a
frequency timebase to generate the necessary timing signals for
controlling A/D conversions, DAC updates, or general-purpose signals
at the I/O connector.

A DAQCard can directly use its internal 20 MHz timebase as the
primary frequency source.

DAQCard E Series User Manual 3-14



National Instruments Corporation

Chapter

Signal Connections

This chapter describes how to make input and output signal connections

to your DAQCard E Series card via the DAQCard I/O connector.

The I/O connector for the DAQCard E Series cards has 68 pins that you
can connect to 68-pin accessories with the PSHR68-68M and SH6868
shielded cables, or the PR68-68F ribbon cable. With the PSHR68-68M
and SH6868 shielded cables or the PR68-50F ribbon cable, you can
connect your DAQCard to 50-pin signal conditioning modules and
terminal blocks.

I/O Connector

Figure 4-1 shows the pin assignments for the 68-pin I/O connector on
the DAQCard-AI-16E-4 and DAQCard-AI-16XE-50. A signal
description follows the connector pinouts.

Warning:

Exceeding the differential and common-mode input ranges distorts your
input signals. Exceeding the maximum input voltage rating can damage
the DAQCard E Series card and your computer. National Instruments is

NOT

liable for any damages resulting from such signal connections. The

maximum input voltage ratings are listed in Tables 4-2 through 4-3 in the

Protection

column.

4



National Instruments Corporation 4-1 DAQCard E Series User Manual

This document was created with FrameMaker 4.0.4

Chapter 4 Signal Connections

ACH8

ACH1
AIGND
ACH10

ACH3
AIGND

ACH4
AIGND
ACH13

ACH6
AIGND

ACH15

Reserved

Reserved

Reserved

DIO4
DGND
DIO1

DIO6
DGND

+5 V
DGND
DGND

PFI0/TRIG1
PFI1/TRIG2

DGND

+5 V
DGND

PFI5/UPDATE*

PFI6/WFTRIG

DGND

PFI9/GPCTR0_GATE

GPCTR0_OUT

FREQ_OUT






34 68
33 67
32 66
31 65
30 64
29 63
28 62
27 61
26 60
25 59
24 58
23 57
22 56
21 55
20 54
19 53
18 52
17 51
16 50
15 49
14 48
13 47
12 46
11 45
10 44

943
842
741
640
539
438
337
236
135

ACH0
AIGND
ACH9
ACH2
AIGND
ACH11
AISENSE
ACH12
ACH5
AIGND
ACH14
ACH7
Reserved
Reserved
Reserved
DGND
DIO0

DIO5
DGND

DIO2
DIO7
DIO3
SCANCLK
EXTSTROBE*
DGND
PFI2/CONVERT*
PFI3/GPCTR1_SOURCE
PFI4/GPCTR1_GATE
GPCTR1_OUT
DGND
PFI7/STARTSCAN
PFI8/GPCTR0_SOURCE
DGND
DGND

Figure 4-1.

I/O Connector Pin Assignment for the DAQCard-AI-16E-4 and DAQCard-AI-16XE-50

DAQCard E Series User Manual 4-2



National Instruments Corporation

Chapter 4 Signal Connections

Table 4-1.

Signal Name

AIGND

ACH<0..15> AIGND Input Analog Input Channels 0 through 15—Each channel pair,

AISENSE AIGND Input Analog Input Sense—This pin serves as the reference node

DGND — — Digital Ground—This pin supplies the reference for the

DIO<0..7> DGND Input or

+5 V DGND Output +5 VDC Source—These pins are fused for up to 250 mA of

SCANCLK DGND Output Scan Clock—This pin pulses once for each A/D conversion

Reference Direction Description

— — Analog Input Ground—These pins are the reference point

I/O Connector Signal Descriptions

for single-ended measurements and the bias current return
point for differential measurements. All three ground
references—AIGND, AOGND, and DGND—are connected
together on your DAQCard E Series card.

ACH<i, i+8> (i = 0..7), can be configured as either one
differential input or two single-ended inputs.

for any of channels ACH<0..15> in NRSE configuration.

digital signals at the I/O connector as well as the +5 VDC
supply. All three ground references—AIGND, AOGND,
and DGND—are connected together on your DAQCard.

Digital I/O signals—DIO6 and 7 can control the up/down

Output

signal of general-purpose counters 0 and 1, respectively.

+5 V supply. The fuse is self-resetting.

in the scanning modes when enabled. The low-to-high edge
indicates when the input signal can be removed from the
input or switched to another signal.

EXTSTROBE* DGND Output External Strobe—This output can be toggled under software

control to latch signals or trigger events on external devices.

PFI0/TRIG1 DGND Input

Output



National Instruments Corporation 4-3 DAQCard E Series User Manual

PFI0/Trigger 1—As an input, this is either one of the PFIs or
the source for the hardware analog trigger. PFI signals are
explained in the
chapter. The hardware analog trigger is explained in the

Analog Trigger

As an output, this is the TRIG1 signal. In posttrigger data
acquisition sequences, a low-to-high transition indicates the
initiation of the acquisition sequence. In pretrigger
applications, a low-to-high transition indicates the initiation
of the pretrigger conversions.

Timing Connections

section in Chapter 2.

section later in this

Chapter 4 Signal Connections

Table 4-1.

Signal Name

PFI1/TRIG2

PFI2/CONVERT* DGND Input

PFI3/GPCTR1_SOURCE DGND Input

PFI4/GPCTR1_GATE DGND Input

Reference Direction Description

DGND Input

I/O Connector Signal Descriptions (Continued)

Output

Output

Output

Output

PFI1/Trigger 2—As an input, this is one of the PFIs.

As an output, this is the TRIG2 signal. In pretrigger
applications, a low-to-high transition indicates the initiation
of the posttrigger conversions. TRIG2 is not used in
posttrigger applications.

PFI2/Convert—As an input, this is one of the PFIs.

As an output, this is the CONVERT* signal. A high-to-low
edge on CONVERT* indicates that an A/D conversion is
occurring.

PFI3/Counter 1 Source—As an input, this is one of the
PFIs.

As an output, this is the GPCTR1_SOURCE signal. This
signal reflects the actual source connected to general­purpose counter 1.

PFI4/Counter 1 Gate—As an input, this is one of the PFIs.

As an output, this is the GPCTR1_GATE signal. This signal
reflects the actual gate signal connected to general-purpose
counter 1.

GPCTR1_OUT DGND Output Counter 1 Output—This output is from the general-purpose

counter 1 output.

PFI5/UPDATE* DGND Input

Output

PFI6/WFTRIG DGND Input

Output

DAQCard E Series User Manual 4-4

PFI5/Update—As an input, this is one of the PFIs.

As an output, this is the UPDATE* signal. A high-to-low
edge on UPDATE* indicates that the analog output primary
group is being updated.

PFI6/Waveform Trigger—As an input, this is one of the
PFIs.

As an output, this is the WFTRIG signal. In timed analog
output sequences, a low-to-high transition indicates the
initiation of the waveform generation.



National Instruments Corporation

Chapter 4 Signal Connections

Table 4-1.

Signal Name

PFI7/STARTSCAN

PFI8/GPCTR0_SOURCE DGND Input

PFI9/GPCTR0_GATE DGND Input

GPCTR0_OUT DGND Output Counter 0 Output—This output is from the general-purpose

FREQ_OUT DGND Output Frequency Output—This output is from the frequency

Reference Direction Description

DGND Input

I/O Connector Signal Descriptions (Continued)

PFI7/Start of Scan—As an input, this is one of the PFIs.

Output

Output

Output

As an output, this is the STARTSCAN signal. This pin
pulses once at the start of each analog input scan in the
interval scan. A low-to-high transition indicates the start of
the scan.

PFI8/Counter 0 Source—As an input, this is one of the
PFIs.

As an output, this is the GPCTR0_SOURCE signal. This
signal reflects the actual source connected to general­purpose counter 0.

PFI9/Counter 0 Gate—As an input, this is one of the PFIs.

As an output, this is the GPCTR0_GATE signal. This signal
reflects the actual gate signal connected to general-purpose
counter 0.

counter 0 output.

generator output.

Table 4-2 shows the I/O signal summary for the DAQCard-AI-16E-4.

Table 4-2.

Signal Name

ACH<0..15>

AISENSE AI 100 GΩ

AIGND AI — — — — — —



National Instruments Corporation 4-5 DAQCard E Series User Manual

Drive Impedance

AI 100 GΩ

I/O Signal Summary, DAQCard-AI-16E-4

Input/

Output

in parallel
with
100 pF

in parallel
with
100 pF

Protection

(Volts)

On/Off

25/10 — — —

25/10 — — —

Source

(mA at V)

Sink

(mA at

V)

Rise

Time

(ns)

Bias

±

200 pA

±

200 pA

Chapter 4 Signal Connections

Table 4-2.

Signal Name

DGND

VCC DO 0.45

DIO<0..7> DIO — Vcc +0.5 13 at (Vcc -0.4) 24 at

SCANCLK DO — — 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

EXTSTROBE* DO — — 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI0/TRIG1 ADIO 10 k

PFI1/TRIG2

PFI2/CONVERT* DIO — V

PFI3/GPCTR1_SOURCE DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI4/GPCTR1_GATE DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

GPCTR1_OUT DO — — 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

Drive Impedance

I/O Signal Summary, DAQCard-AI-16E-4 (Continued)

Protection

Input/

Output

DO — — — — — —

Ω

Ω

DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

(Volts)

On/Off

Short-circuit
to ground

Vcc +0.5/±35

+0.5

cc

Source

(mA at V)

250 at V

cc

3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

Sink

(mA at

— — —

0.4

V)

Rise

Time

(ns)

1.1 50 kΩ pu

Bias

1

2

PFI5/UPDATE* DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI6/WFTRIG DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI7/STARTSCAN DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI8/GPCTR0_SOURCE DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI9/GPCTR0_GATE DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

GPCTR0_OUT DO — — 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

DAQCard E Series User Manual 4-6



National Instruments Corporation

Chapter 4 Signal Connections

Signal Name

FREQ_OUT

Table 4-2.

Drive Impedance

I/O Signal Summary, DAQCard-AI-16E-4 (Continued)

Protection

Input/

Output

(Volts)

On/Off

DO — — 3.5 at (Vcc-0.4) 5 at 0.4 1.5 50 kΩ pu

Source

(mA at V)

AI = Analog Input DIO = Digital Input/Output pu = pullup
DO = Digital Output ADIO = Analog/Digital Input/Output

1

DIO <6..7> are also pulled up with a 10 kΩ resistor.

2

Also pulled down with a 10 kΩ resistor.

Warning:

Unless specifically indicated in the

Protection

column of Table 4-2, the outputs of DAQCard E Series cards
are not short-circuit protected. Exceeding the output limit in the
DAQCard

.

Source

and

Sink

(mA at

Sink

Rise

Time

V)

(ns)

columns can damage your

Bias



National Instruments Corporation 4-7 DAQCard E Series User Manual

Chapter 4 Signal Connections

Table 4-3 shows the I/O signal summary for the

DAQCard-AI-16XE-50.

Table 4-3.

Signal Name

ACH<0..15>

AISENSE AI 20 GΩ in

AIGND AI — — — — — —

DGND DO — — — — — —

VCC DO 0.45

DIO<0..7> DIO — Vcc +0.5 13 at (Vcc -0.4) 24 at 0.4 1.1 50 kΩ pu

SCANCLK

EXTSTROBE* DO — — 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

Drive Impedance

AI 20 GΩ in

DO — — 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

I/O Signal Summary, DAQCard-AI-16XE-50

Input/

Output

parallel
with
100 pF

parallel
with
100 pF

Ω

Protection

(Volts)

On/Off

25/15 — — —

25/15 — — —

Short-circuit
to ground

Source

(mA at V)

250 at V

cc

Sink

(mA at

— — —

V)

Rise

Time

(ns)

±

10 nA

±

10 nA

Bias

1

PFI0/TRIG1 DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI1/TRIG2 DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI2/CONVERT* DIO — V

PFI3/GPCTR1_SOURCE DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI4/GPCTR1_GATE DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

GPCTR1_OUT DO — — 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI5/UPDATE* DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI6/WFTRIG DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI7/STARTSCAN DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

PFI8/GPCTR0_SOURCE DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

DAQCard E Series User Manual 4-8

+0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

cc



National Instruments Corporation

Chapter 4 Signal Connections

Table 4-3.

Signal Name

PFI9/GPCTR0_GATE

GPCTR0_OUT DO — — 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

FREQ_OUT DO — — 3.5 at (Vcc-0.4) 5 at 0.4 1.5 50 kΩ pu

AI = Analog Input DIO = Digital Input/Output pu = pullup
DO = Digital Output

1

DIO <6..7> are also pulled up with a 10 kΩ resistor.

Warning:

Unless specifically indicated in the
are not short-circuit protected. Exceeding the output limit in the
DAQCard

.

I/O Signal Summary, DAQCard-AI-16XE-50 (Continued)

Drive Impedance

Input/

Output

DIO — Vcc +0.5 3.5 at (Vcc -0.4) 5 at 0.4 1.5 50 kΩ pu

Protection

Protection

Source

(Volts)

On/Off

column of Table 4-3, the outputs of DAQCard E Series cards

(mA at V)

Source

Sink

and

(mA at

Sink

Time

V)

columns can damage your

Rise

(ns)

Bias



National Instruments Corporation 4-9 DAQCard E Series User Manual

Chapter 4 Signal Connections

Analog Input Signal Connections

The analog input signals are ACH<0..15>, AISENSE, and AIGND.
The ACH<0..15> signals are tied to the 16 analog input channels of
your DAQCard. In single-ended mode, signals connected to
ACH<0..15> are routed to the positive input of the DAQCard PGIA. In
differential mode, signals connected to ACH<0..7> are routed to the
positive input of the PGIA, and signals connected to ACH<8..15> are
routed to the negative input of the PGIA.

Warning:

Exceeding the differential and common-mode input ranges distorts your
input signals1. Exceeding the maximum input voltage rating can damage
the DAQCard and your computer. National Instruments is

NOT

liable for
any damages resulting from such signal connections. The maximum input
voltage ratings are listed in Tables 4-2 through 4-3 in the

Protection

column.

In NRSE mode, the AISENSE signal is connected internally to the
negative input of the DAQCard PGIA when their corresponding
channels are selected. In DIFF and RSE modes, this signal is left
unconnected.

AIGND is an analog input common signal that is routed directly to the
ground tie point on the DAQCards. You can use this signal for a
general analog ground tie point to your DAQCard, if necessary.

Connection of analog input signals to your DAQCard depends on the
configuration of the analog input channels you are using and the type
of input signal source. With the different configurations, you can use

1.

Note that exceeding input ranges on any channel can affect the measurements on a different channel

even if the other channel is well within the input range

DAQCard E Series User Manual 4-10

.



National Instruments Corporation

This document was created with FrameMaker 4.0.4

Chapter 4 Signal Connections

the PGIA in different ways. Figure 4-2 shows a diagram of your
DAQCard PGIA.

Instrumentation

Amplifier

V

in+

+

PGIA

V

in-

-

+

V

m

Measured

Voltage

-

Vm = [V

Figure 4-2.

The PGIA applies gain and common-mode voltage rejection and
presents high input impedance to the analog input signals connected to
your DAQCard. Signals are routed to the positive and negative inputs
of the PGIA through input multiplexers on the DAQCard. The PGIA
converts two input signals to a signal that is the difference between the
two input signals multiplied by the gain setting of the amplifier. The
amplifier output voltage is referenced to the ground for the DAQCard.
Your DAQCard ADC measures this output voltage when it performs
A/D conversions.

- V

]* Gain

in+

in-

DAQCard E Series PGIA

You must reference all signals to ground either at the source device or
at the DAQCard. If you have a floating source, you should reference
the signal to ground by using the RSE input mode or the DIFF input
configuration with bias resistors (see the

Nonreferenced or Floating Signal Sources

Differential Connections for

section later in this
chapter). If you have a grounded source, you should not reference the
signal to AIGND. You can avoid this reference by using DIFF or NRSE
input configurations.



National Instruments Corporation 4-11 DAQCard E Series User Manual

Chapter 4 Signal Connections

Types of Signal Sources

When configuring the input channels and making signal connections,
you must first determine whether the signal sources are floating or
ground-referenced. The following sections describe these two types of
signals.

Floating Signal Sources

A floating signal source is one that is not connected in any way to the
building ground system but, rather, has an isolated ground-reference
point. Some examples of floating signal sources are outputs of
transformers, thermocouples, battery-powered devices, optical isolator
output, and isolation amplifiers. An instrument or device that has an
isolated output is a floating signal source. You must tie the ground
reference of a floating signal to your DAQCard analog input ground to
establish a local or onboard reference for the signal. Otherwise, the
measured input signal varies as the source floats out of the
common-mode input range.

Ground-Referenced Signal Sources

A ground-referenced signal source is one that is connected in some
way to the building system ground and is, therefore, already connected
to a common ground point with respect to the DAQCard, assuming that
the computer is plugged into the same power system. Nonisolated
output of instruments and devices that plug into the building power
system falls into this category.

The difference in ground potential between two instruments connected
to the same building power system is typically between 1 and 100 mV
but can be much higher if power distribution circuits are not properly
connected. If a grounded signal source is improperly measured, this
difference may appear as an error in the measurement. The connection
instructions for grounded signal sources are designed to eliminate this
ground potential difference from the measured signal.

Input Configurations

You can configure your DAQCard for one of three input modes—
NRSE, RSE, or DIFF. The following sections discuss the use of
single-ended and differential measurements and considerations for
measuring both floating and ground-referenced signal sources.

DAQCard E Series User Manual 4-12



National Instruments Corporation

Chapter 4 Signal Connections

Figure 4-3 summarizes the recommended input configuration for both
types of signal sources.

Signal Source Type

Input

Differential

(DIFF)

Single-Ended —

Ground

Referenced

(RSE)

Floating Signal Source

(Not Connected to Building Ground)

Examples

• Ungrounded Thermocouples

• Signal conditioning with isolated outputs

• Battery devices

+

V

1

-

ACH(+)

ACH (-)

R

+

-

AIGND

See text for information on bias resistors.

+

V

1

-

ACH

AIGND

+

-

Grounded Signal Source

Examples

• Plug-in instruments with
nonisolated outputs

+

V

1

-

NOT RECOMMENDED

+

V

1

-

+ Vg -

ACH(+)

ACH (-)

ACH

+

-

AIGND

+

-

Ground-loop losses, Vg, are added to
measured signal

Single-Ended —

Nonreferenced

(NRSE)

+

V

1

-

ACH

AISENSE

+

-

R

AIGND

+

V

1

-

ACH

AISENSE

+

-

AIGND

See text for information on bias resistors.

Figure 4-3.



National Instruments Corporation 4-13 DAQCard E Series User Manual

Summary of Analog Input Connections

Chapter 4 Signal Connections

Differential Connection Considerations (DIFF Input Configuration)

A differential connection is one in which the DAQCard analog input
signal has its own reference signal or signal return path. These
connections are available when the selected channel is configured in
DIFF input mode. The input signal is tied to the positive input of the
PGIA, and its reference signal, or return, is tied to the negative input of
the PGIA.

When you configure a channel for differential input, each signal uses
two multiplexer inputs—one for the signal and one for its reference
signal. Therefore, with a differential configuration for every channel,
up to eight analog input channels are available.

You should use differential input connections for any channel that
meets any of the following conditions:

• The input signal is low level (less than 1 V).

• The leads connecting the signal to the DAQCard are greater than

10 ft (3 m).

• The input signal requires a separate ground-reference point or

return signal.

• The signal leads travel through noisy environments.
Differential signal connections reduce picked-up noise and increase

common-mode noise rejection. Differential signal connections also
allow input signals to float within the common-mode limits of the
PGIA.

DAQCard E Series User Manual 4-14



National Instruments Corporation

Ground-

Referenced

Signal

Source

Chapter 4 Signal Connections

Differential Connections for Ground-Referenced Signal Sources

Figure 4-4 shows how to connect a ground-referenced signal source to
a channel on a DAQCard configured in DIFF input mode.

ACH<0..7>

+

V

s

-

Instrumentation

Amplifier

+

Common-

Mode

Noise and

Ground

Potential

I/O Connector

+

V

cm

-

Figure 4-4.

PGIA

ACH<8..15>

-

Input Multiplexers

AISENSE

AIGND

Selected Channel in DIFF Configuration

+

m

Measured

Voltage

-

V

Differential Input Connections for Ground-Referenced Signals

With this type of connection, the PGIA rejects both the common-mode
noise in the signal and the ground potential difference between the
signal source and the DAQCard ground, shown as Vcm in Figure 4-4.



National Instruments Corporation 4-15 DAQCard E Series User Manual

Chapter 4 Signal Connections

Bias
Resistors 
(see text)

Floating

Signal

Source

+

V

S

-

Differential Connections for Nonreferenced or Floating Signal Sources

Figure 4-5 shows how to connect a floating signal source to a channel
on a DAQCard configured in DIFF input mode.

ACH<0..7>

Instrumentation

Amplifier

+

Bias

Current

Return

Paths

I/O Connector

PGIA

ACH<8..15>

V

m

Figure 4-5.

-

Input Multiplexers

AISENSE

AIGND

Selected Channel in DIFF Configuration

Differential Input Connections for Nonreferenced Signals

Figure 4-5 shows two bias resistors connected in parallel with the
signal leads of a floating signal source. If you do not use the resistors
and the source is truly floating, the source is not likely to remain within
the common-mode signal range of the PGIA, and the PGIA will
saturate, causing erroneous readings. You must reference the source to
AIGND. The easiest way is simply to connect the positive side of the
signal to the positive input of the PGIA and connect the negative side
of the signal to AIGND as well as to the negative input of the PGIA,

+

Measured

Voltage

-

DAQCard E Series User Manual 4-16



National Instruments Corporation

Chapter 4 Signal Connections

without any resistors at all. This connection works well for
DC-coupled sources with low source impedance (less than 100 Ω).

However, for larger source impedances, this connection leaves the
differential signal path significantly out of balance. Noise that couples
electrostatically onto the positive line does not couple onto the
negative line because it is connected to ground. Hence, this noise
appears as a differential-mode signal instead of a common-mode
signal, so the PGIA does not reject it. In this case, instead of directly
connecting the negative line to AIGND, connect it to AIGND through
a resistor that is about 100 times the equivalent source impedance. The
resistor puts the signal path nearly in balance, so that about the same
amount of noise couples onto both connections, yielding better
rejection of electrostatically coupled noise. Also, this configuration
does not load down the source (other than the very high input
impedance of the PGIA).

You can fully balance the signal path by connecting another resistor of
the same value between the positive input and AIGND, as shown in
Figure 4-5. This fully-balanced configuration offers slightly better
noise rejection but has the disadvantage of loading the source down
with the DAQCard combination (sum) of the two resistors. If, for
example, the source impedance is 2 kΩ and each of the two resistors is
100 kΩ, the resistors load down the source with 200 kΩ and produce a

-1% gain error.
Both inputs of the PGIA require a DC path to ground in order for the

PGIA to work. If the source is AC coupled (capacitively coupled), the
PGIA needs a resistor between the positive input and AIGND. If the
source has low impedance, choose a resistor that is large enough not to
significantly load the source but small enough not to produce
significant input offset voltage as a result of input bias current
(typically 100 kΩ to 1 MΩ). In this case, you can tie the negative input
directly to AIGND. If the source has high output impedance, balance
the signal path as previously described using the same value resistor on
both the positive and negative inputs; be aware that there is some gain
error from loading down the source.



National Instruments Corporation 4-17 DAQCard E Series User Manual

Chapter 4 Signal Connections

Single-Ended Connection Considerations

A single-ended connection is one in which the DAQCard E Series card
analog input signal is referenced to a ground that can be shared with
other input signals. The input signal is tied to the positive input of the
PGIA, and the ground is tied to the negative input of the PGIA.

When every channel is configured for single-ended input, up to 16
analog input channels are available.

Use single-ended input connections for any input signal that meets the
following conditions:

• The input signal is high level (greater than 1 V).

• The leads connecting the signal to the DAQCard are less than 10 ft

(3 m).

• The input signal can share a common reference point with other

signals.

DIFF input connections are recommended for greater signal integrity
for any input signal that does not meet the preceding conditions.

You can software-configure the DAQCard channels for two different
types of single-ended connections—RSE configuration and NRSE
configuration. Use the RSE configuration for floating signal sources;
in this case, the DAQCard provides the reference ground point for the
external signal. Use the NRSE input configuration for ground­referenced signal sources; in this case, the external signal supplies its
own reference ground point and the DAQCard should not supply one.

In single-ended configurations, more electrostatic and magnetic noise
couples into the signal connections than in differential configurations.
The coupling is the result of differences in the signal path. Magnetic
coupling is proportional to the area between the two signal conductors.
Electrical coupling is a function of how much the electric field differs
between the two conductors.

DAQCard E Series User Manual 4-18



National Instruments Corporation

Chapter 4 Signal Connections

Single-Ended Connections for Floating Signal Sources (RSE Configuration)

Figures 4-6 shows how to connect a floating signal source to a channel
on a DAQCard configured for RSE mode.

Floating

Signal

Source

Figure 4-6.

+

V

s

-

I/O Connector

Single-Ended Input Connections for Nonreferenced or Floating Signals

Single-Ended Connections for Grounded Signal Sources (NRSE Configuration)

To measure a grounded signal source with a single-ended
configuration, you must configure your DAQCard in the NRSE input
configuration. The signal is then connected to the positive input of the
DAQCard PGIA, and the signal local ground reference is connected to
the negative input of the PGIA. The ground point of the signal should,
therefore, be connected to the AISENSE pin. Any potential difference
between the DAQCard ground and the signal ground appears as a
common-mode signal at both the positive and negative inputs of the
PGIA, and this difference is rejected by the amplifier. If the input
circuitry of a DAQCard were referenced to ground, in this situation as
in the RSE input configuration, this difference in ground potentials
would appear as an error in the measured voltage.












ACH<0..15>

Input Multiplexers

AISENSE

AIGND

Selected Channel in RSE Configuration

Instrumentation

+

PGIA

-

Amplifier

V

m

+

Measured

Voltage

-



National Instruments Corporation 4-19 DAQCard E Series User Manual

Chapter 4 Signal Connections

Figure 4-7 shows how to connect a grounded signal source to a channel
on a DAQCard configured for NRSE mode.

ACH<0..15>

+

Input Multiplexers

AIGND

Selected Channel in NRSE Configuration

AISENSE

-

Ground-

Referenced

Signal

Source

Common-

Mode
Noise

and Ground

Potential

+

V

s

-

+

V

cm

-

I/O Connector

Figure 4-7.












Single-Ended Input Connections for Ground-Referenced Signals

Common-Mode Signal Rejection Considerations

Figures 4-4 and 4-7 show connections for signal sources that are
already referenced to some ground point with respect to the DAQCard.
In these cases, the PGIA can reject any voltage caused by ground
potential differences between the signal source and the DAQCard. In
addition, with differential input connections, the PGIA can reject
common-mode noise pickup in the leads connecting the signal sources
to the DAQCard. The PGIA can reject common-mode signals as long

+

as V

in

DAQCard-AI-16XE-50 has the additional restriction that (V
added to the gain times (V
At gains of 10 and 100, this is roughly equivalent to restricting the two
input voltages to within ±8 V of AIGND.

and V

-

are both within ±11 V of AIGND.

in

+

-

- V

in

) must be within ±26 V of AIGND.

in

Instrumentation

Amplifier

PGIA

V

m

The

+

Measured

-

Voltage

+

+ V

in

-

)

in

DAQCard E Series User Manual 4-20



National Instruments Corporation

Digital I/O Signal Connections

The digital I/O signals are DIO<0..7> and DGND. The DIO<0..7>
signals make up the DIO port, and DGND is the ground reference
signal for this port. You can program all lines individually to be inputs
or outputs.

Chapter 4 Signal Connections

Warning:

LED

+5 V

Exceeding the maximum input voltage ratings, which are listed in
Tables 4-2 through 4-3, can damage the DAQCard and the computer.
National Instruments is

NOT

liable for any damages resulting from such

signal connections.

Figure 4-8 shows signal connections for three typical digital
I/O applications.

+5 V

DIO<4..7>

TTL Signal

DIO<0..3>

Switch

DGND

I/O Connector

E Series Card

Figure 4-8.



National Instruments Corporation 4-21 DAQCard E Series User Manual

Digital I/O Connections

Chapter 4 Signal Connections

Figure 4-8 shows DIO<0..3> configured for digital input and
DIO<4..7> configured for digital output. Digital input applications
include receiving TTL signals and sensing external device states such
as the state of the switch shown in the figure. Digital output
applications include sending TTL signals and driving external devices
such as the LED shown in the figure.

Power Connections

Two pins on the I/0 connector supply +5 V from the computer power
supply via a self-resetting fuse. The fuse will reset automatically
within a few seconds after the overcurrent condition is removed. These
pins are referenced to DGND and can be used to power external digital
circuitry.

• Power rating +4.65 to +5.25 VDC

at 250 mA

Warning:

Do not, under any circumstances, connect these +5 V power pins directly
to analog or digital ground or to any other voltage source on the DAQCard
or any other device. Doing so can damage the DAQCard and the computer.
National Instruments is
connection.

Timing Connections

Warning:

Exceeding the maximum input voltage ratings, which are listed in
Tables 4-2 through 4-3, can damage the DAQCard and the computer.
National Instruments in
signal connections.

All external control over the timing of your DAQCard is routed
through the 10 programmable function inputs labeled PFI0 through
PFI9. These signals are explained in detail in the

Function Input Connections

outputs they are not programmable and reflect the state of many data
acquisition, waveform generation, and general-purpose timing signals.
There are five other dedicated outputs for the remainder of the timing
signals. As inputs, the PFI signals are programmable and can control
any data acquisition, waveform generation, and general-purpose
timing signals.

NOT

liable for damages resulting from such a

NOT

liable for any damages resulting from such

Programmable

section. These PFIs are bidirectional; as

DAQCard E Series User Manual 4-22

This document was created with FrameMaker 4.0.4



National Instruments Corporation

Chapter 4 Signal Connections

TRIG1
Source

The data acquisition signals are explained in the

Timing Connections

timing signals are explained in the

Connections

section later in this chapter.

section later in this chapter. The general-purpose

General-Purpose Timing Signal

Data Acquisition

All digital timing connections are referenced to DGND. This reference
is demonstrated in Figure 4-9, which shows how to connect an external
TRIG1 source and an external CONVERT* source to two of the
DAQCard PFI pins.

PFI0/TRIG1

PFI2/CONVERT*

CONVERT*

Source

DGND

I/O Connector

E Series Card

Figure 4-9.



National Instruments Corporation 4-23 DAQCard E Series User Manual

Timing I/O Connections

Chapter 4 Signal Connections

Programmable Function Input Connections

There are a total of 13 internal timing signals that you can externally
control from the PFI pins. The source for each of these signals is
software selectable from any of the PFIs when you want external
control. This flexible routing scheme reduces the need to change the
physical wiring to the DAQCard I/O connector for different
applications requiring alternative wiring.

You can individually enable each of the PFI pins to output a specific
internal timing signal. For example, if you need the CONVERT* signal
as an output on the I/O connector, software can turn on the output
driver for the PFI2/CONVERT* pin. Be careful not to drive a PFI
signal externally when it is configured as an output.

As an input, you can individually configure each PFI for edge or level
detection and for polarity selection, as well. You can use the polarity
selection for any of the 13 timing signals, but the edge or level
detection will depend upon the particular timing signal being
controlled. The detection requirements for each timing signal are listed
within the section that discusses that individual signal.

In edge-detection mode, the minimum pulse width required is 10 ns.
This applies for both rising-edge and falling-edge polarity settings.
There is no maximum pulse-width requirement in edge-detection
mode.

In level-detection mode, there are no minimum or maximum
pulse-width requirements imposed by the PFIs themselves, but there
may be limits imposed by the particular timing signal being controlled.
These requirements are listed later in this chapter.

Data Acquisition Timing Connections

The data acquisition timing signals are SCANCLK, EXTSTROBE*,
TRIG1, TRIG2, STARTSCAN, CONVERT*, AIGATE, and
SISOURCE.

Posttriggered data acquisition allows you to view only data that is
acquired after a trigger event is received. A typical posttriggered data
acquisition sequence is shown in Figure 4-10. Pretriggered data
acquisition allows you to view data that is acquired before the trigger
of interest in addition to data acquired after the trigger. Figure 4-11

DAQCard E Series User Manual 4-24



National Instruments Corporation

Chapter 4 Signal Connections

shows a typical pretriggered data acquisition sequence. The description
for each signal shown in these figures is included later in this chapter.

TRIG1

STARTSCAN

CONVERT*

TRIG1

TRIG2

STARTSCAN

CONVERT*

Scan Counter

Scan Counter

Don't Care

Figure 4-10.

Figure 4-11.

13042

Typical Posttriggered Acquisition

01231 0222

Typical Pretriggered Acquisition



National Instruments Corporation 4-25 DAQCard E Series User Manual

Chapter 4 Signal Connections

SCANCLK Signal

SCANCLK is an output-only signal that generates a pulse with the
leading edge occurring approximately 50 to 100 ns after an A/D
conversion begins. The polarity of this output is software-selectable
but is typically configured so that a low-to-high leading edge can clock
external analog input multiplexers indicating when the input signal has
been sampled and can be removed. This signal has a 400 to 500 ns
pulse width and is software enabled. Figure 4-12 shows the timing for
the SCANCLK signal,

CONVERT*

t

SCANCLK

d

t

w

t

= 50 to 100 ns

d

t

= 400 to 500 ns

w

Figure 4-12.

DAQCard E Series User Manual 4-26

SCANCLK Signal Timing



National Instruments Corporation

Chapter 4 Signal Connections

EXTSTROBE* Signal

EXTSTROBE* is an output-only signal that generates either a single
pulse or a sequence of eight pulses in the hardware-strobe mode. An
external device can use this signal to latch signals or to trigger events.
In the single-pulse mode, software controls the level of the
EXTSTROBE* signal. A 10 and 1.2 µs clocks are available for
generating a sequence of eight pulses in the hardware-strobe mode.
Figure 4-13 shows the timing for the hardware-strobe mode
EXTSTROBE* signal.

V

OH

V

OL

t

t

w

w

t

= 600 ns or 5 µs

w

Figure 4-13.

EXTSTROBE* Signal Timing

TRIG1 Signal

Any PFI pin can externally input the TRIG1 signal, which is available
as an output on the PFI0/TRIG1 pin.

Refer to Figures 4-10 and 4-11 for the relationship of TRIG1 to the
data acquisition sequence.

As an input, the TRIG1 signal is configured in the edge-detection
mode. You can select any PFI pin as the source for TRIG1 and
configure the polarity selection for either rising or falling edge. The
selected edge of the TRIG1 signal starts the data acquisition sequence
for both posttriggered and pretriggered acquisitions. The DAQCards
support analog triggering on the PFI0/TRIG1 pin. See Chapter 3 for
more information on analog triggering.

As an output, the TRIG1 signal reflects the action that initiates a data
acquisition sequence. This is true even if the acquisition is being
externally triggered by another PFI. The output is an active high pulse
with a pulse width of 50 to 100 ns. This output is set to tri-state at
startup.



National Instruments Corporation 4-27 DAQCard E Series User Manual

Chapter 4 Signal Connections

Rising-edge
polarity

Falling-edge
polarity

Figures 4-14 and 4-15 show the input and output timing requirements
for the TRIG1 signal.

t

w

t

= 10 ns minimum

w

Figure 4-14.

Figure 4-15.

TRIG1 Input Signal Timing

t

w

t

= 50-100 ns

w

TRIG1 Output Signal Timing

The DAQCard also uses the TRIG1 signal to initiate pretriggered data
acquisition operations. In most pretriggered applications, the TRIG1
signal is generated by a software trigger. Refer to the TRIG2 signal
description for a complete description of the use of TRIG1 and TRIG2
in a pretriggered data acquisition operation.

DAQCard E Series User Manual 4-28



National Instruments Corporation

Chapter 4 Signal Connections

TRIG2 Signal

Any PFI pin can externally input the TRIG2 signal, which is available
as an output on the PFI1/TRIG2 pin.

Refer to Figure 4-11 for the relationship of TRIG2 to the data
acquisition sequence.

As an input, the TRIG2 signal is configured in the edge-detection
mode. You can select any PFI pin as the source for TRIG2 and
configure the polarity selection for either rising or falling edge. The
selected edge of the TRIG2 signal initiates the posttriggered phase of a
pretriggered acquisition sequence. In pretriggered mode, the TRIG1
signal initiates the data acquisition. The scan counter indicates the
minimum number of scans before TRIG2 can be recognized. After the
scan counter decrements to zero, it is loaded with the number of
posttrigger scans to acquire while the acquisition continues. The
DAQCard ignores the TRIG2 signal if it is asserted prior to the scan
counter decrementing to zero. After the selected edge of TRIG2 is
received, the DAQCard acquires a fixed number of scans and the
acquisition stops. This mode acquires data both before and after
receiving TRIG2.

As an output, the TRIG2 signal reflects the posttrigger in a
pretriggered acquisition sequence. This is true even if the acquisition
is being externally triggered by another PFI. The TRIG2 signal is not
used in posttriggered data acquisition. The output is an active high
pulse with a pulse width of 50 to 100 ns. This signal is set to input
(High-Z) at startup.



National Instruments Corporation 4-29 DAQCard E Series User Manual

This document was created with FrameMaker 4.0.4

Chapter 4 Signal Connections

Rising-edge
polarity

Falling-edge
polarity

Figures 4-16 and 4-17 show the input and output timing requirements
for the TRIG2 signal.

t

w

t

= 10 ns minimum

w

Figure 4-16.

TRIG2 Input Signal Timing

t

w

Figure 4-17.

TRIG2 Output Signal Timing

t

w

= 50-100 ns

STARTSCAN Signal

Any PFI pin can externally input the STARTSCAN signal, which is
available as an output on the PFI7/STARTSCAN pin.

Refer to Figures 4-10 and 4-11 for the relationship of STARTSCAN to
the data acquisition sequence.

As an input, the STARTSCAN signal is configured in the
edge-detection mode. You can select any PFI pin as the source for
STARTSCAN and configure the polarity selection for either rising or
falling edge. The selected edge of the STARTSCAN signal initiates a

DAQCard E Series User Manual 4-30



National Instruments Corporation

Chapter 4 Signal Connections

scan. The sample interval counter is started if you select internally
triggered CONVERT*.

As an output, the STARTSCAN signal reflects the actual start pulse
that initiates a scan. This is true even if the starts are externally
triggered by another PFI. You have two output options. The first is an
active high pulse with a pulse width of 50 to 100 ns, which indicates
the start of the scan. The second action is an active high pulse that
terminates at the start of the last conversion in the scan, which indicates
a scan in progress. STARTSCAN will be deasserted t

after the last

off

conversion in the scan is initiated. This output is set to tri-state at
startup.

Figures 4-18 and 4-19 show the input and output timing requirements
for the STARTSCAN signal.

t

w

Rising-edge
polarity

Falling-edge
polarity

t

= 10 ns minimum

w

Figure 4-18.



National Instruments Corporation 4-31 DAQCard E Series User Manual

STARTSCAN Input Signal Timing

Chapter 4 Signal Connections

STARTSCAN

Start Pulse

CONVERT*

STARTSCAN

t

w

tw = 50-100 ns

a. Start of Scan



t



off

b. Scan in Progress, Two Conversions per Scan

Figure 4-19.

STARTSCAN Output Signal Timing

The CONVERT* pulses are masked off until the DAQCard generates
the STARTSCAN signal. If you are using internally generated
conversions, the first CONVERT* will appear when the onboard
sample interval counter reaches zero. If you select an external
CONVERT*, the first external pulse after STARTSCAN will generate
a conversion. The STARTSCAN pulses should be separated by at least
one scan period.

A counter on your DAQCard internally generates the STARTSCAN
signal unless you select some external source. This counter is started
by the TRIG1 signal and is stopped either by software or by the sample
counter.

DAQCard E Series User Manual 4-32

= 10 ns minimum

t

off





National Instruments Corporation

Chapter 4 Signal Connections

Scans generated by either an internal or external STARTSCAN signal
are inhibited unless they occur within a data acquisition sequence.
Scans occurring within a data acquisition sequence may be gated by
either the hardware (AIGATE) signal or software command register
gate.

CONVERT* Signal

Any PFI pin can externally input the CONVERT* signal, which is
available as an output on the PFI2/CONVERT* pin.

Refer to Figures 4-10 and 4-11 for the relationship of STARTSCAN to
the data acquisition sequence.

As an input, the CONVERT* signal is configured in the edge-detection
mode. You can select any PFI pin as the source for CONVERT* and
configure the polarity selection for either rising or falling edge. The
selected edge of the CONVERT* signal initiates an A/D conversion.

As an output, the CONVERT* signal reflects the actual convert pulse
that is connected to the ADC. This is true even if the conversions are
externally generated by another PFI. The output is an active low pulse
with a pulse width of 50 to 100 ns. This signal is set to input (High-Z)
at startup.

Figures 4-20 and 4-21 show the input and output timing requirements
for the CONVERT* signal.

t

w

Rising-edge
polarity

Falling-edge
polarity

t

= 10 ns minimum

w

Figure 4-20.



National Instruments Corporation 4-33 DAQCard E Series User Manual

CONVERT* Input Signal Timing

Chapter 4 Signal Connections

t

= 50-100 ns

w

t

w

Figure 4-21.

CONVERT* Output Signal Timing

The ADC switches to hold mode within 60 ns of the selected edge. This
hold-mode delay time is a function of temperature and does not vary
from one conversion to the next. Separate the CONVERT* pulses by
at least one conversion period.

The sample interval counter on the DAQCard normally generates the
CONVERT* signal unless you select some external source. The
counter is started by the STARTSCAN signal and continues to count
down and reload itself until the scan is finished. It then reloads itself in
readiness for the next STARTSCAN pulse.

A/D conversions generated by either an internal or external
CONVERT* signal are inhibited unless they occur within a data
acquisition sequence. Scans occurring within a data acquisition
sequence may be gated by either the hardware (AIGATE) signal or
software command register gate.

AIGATE Signal

Any PFI pin can externally input the AIGATE signal, which is not
available as an output on the I/O connector. The AIGATE signal can
mask off scans in a data acquisition sequence. You can configure the
PFI pin you select as the source for the AIGATE signal in either the
level-detection or edge-detection mode. You can configure the polarity
selection for the PFI pin for either active high or active low.

In the level-detection mode if AIGATE is active, the STARTSCAN
signal is masked off and no scans can occur. In the edge-detection

DAQCard E Series User Manual 4-34



National Instruments Corporation

Chapter 4 Signal Connections

mode, the first active edge disables the STARTSCAN signal, and the
second active edge enables STARTSCAN.

The AIGATE signal can neither stop a scan in progress nor continue a
previously gated-off scan; in other words, once a scan has started,
AIGATE does not gate off conversions until the beginning of the next
scan and, conversely, if conversions are being gated off, AIGATE does
not gate them back on until the beginning of the next scan.

SISOURCE Signal

Any PFI pin can externally input the SISOURCE signal, which is not
available as an output on the I/O connector. The onboard scan interval
counter uses the SISOURCE signal as a clock to time the generation of
the STARTSCAN signal. You must configure the PFI pin you select as
the source for the SISOURCE signal in the level-detection mode. You
can configure the polarity selection for the PFI pin for either active
high or active low.

The maximum allowed frequency is 20 MHz, with a minimum pulse
width of 23 ns high or low. There is no minimum frequency limitation.

Either the 20 MHz or 100 kHz internal timebase generates the
SISOURCE signal unless you select some external source. Figure 4-22
shows the timing requirements for the SISOURCE signal.

t

p

t

Figure 4-22.



National Instruments Corporation 4-35 DAQCard E Series User Manual

t

w

w

t

= 50 ns minimum

p

t

= 23 ns minimum

w

SISOURCE Signal Timing

Chapter 4 Signal Connections

UISOURCE Signal

Any PFI pin can externally input the UISOURCE signal, which is not
available as an output on the I/O connector. The UI counter uses the
UISOURCE signal as a clock to time the generation of the UPDATE*
signal. You must configure the PFI pin you select as the source for the
UISOURCE signal in the level-detection mode. You can configure the
polarity selection for the PFI pin for either active high or active low.
Figure 4-23 shows the timing requirements for the UISOURCE signal.

t

p

t

Figure 4-23.

t

w

w

t

= 50 ns minimum

p

t

= 23 ns minimum

w

UISOURCE Signal Timing

The maximum allowed frequency is 20 MHz, with a minimum pulse
width of 23 ns high or low. There is no minimum frequency limitation.

Either the 20 MHz or 100 kHz internal timebase normally generates
the UISOURCE signal unless you select some external source.

DAQCard E Series User Manual 4-36



National Instruments Corporation

Chapter 4 Signal Connections

General-Purpose Timing Signal Connections

The general-purpose timing signals are GPCTR0_SOURCE,
GPCTR0_GATE, GPCTR0_OUT, GPCTR0_UP_DOWN,
GPCTR1_SOURCE, GPCTR1_GATE, GPCTR1_OUT,
GPCTR1_UP_DOWN, and FREQ_OUT.

GPCTR0_SOURCE Signal

Any PFI pin can externally input the GPCTR0_SOURCE signal, which
is available as an output on the PFI8/GPCTR0_SOURCE pin.

As an input, the GPCTR0_SOURCE signal is configured in the
edge-detection mode. You can select any PFI pin as the source for
GPCTR0_SOURCE and configure the polarity selection for either
rising or falling edge.

As an output, the GPCTR0_SOURCE signal reflects the actual clock
connected to general-purpose counter 0. This is true even if another
PFI is externally inputting the source clock. This signal is set to input
(High-Z) at startup.

Figure 4-24 shows the timing requirements for the GPCTR0_SOURCE
signal.

t

p

t

Figure 4-24.

t

w

w

t

= 50 ns minimum

p

t

= 23 ns minimum

w

GPCTR0_SOURCE Signal Timing

The maximum allowed frequency is 20 MHz, with a minimum pulse
width of 23 ns high or low. There is no minimum frequency limitation.



National Instruments Corporation 4-37 DAQCard E Series User Manual

This document was created with FrameMaker 4.0.4

Chapter 4 Signal Connections

The 20 MHz or 100 kHz timebase normally generates the
GPCTR0_SOURCE signal unless you select some external source.

GPCTR0_GATE Signal

Any PFI pin can externally input the GPCTR0_GATE signal, which is
available as an output on the PFI9/GPCTR0_GATE pin.

As an input, the GPCTR0_GATE signal is configured in the
edge-detection mode. You can select any PFI pin as the source for
GPCTR0_GATE and configure the polarity selection for either rising
or falling edge. You can use the gate signal in a variety of different
applications to perform actions such as starting and stopping the
counter, generating interrupts, saving the counter contents, and so on.

As an output, the GPCTR0_GATE signal reflects the actual gate signal
connected to general-purpose counter 0. This is true even if the gate is
being externally generated by another PFI. This signal is set to input
(High-Z) at startup.

Figure 4-25 shows the timing requirements for the GPCTR0_GATE
signal.

Rising-edge
polarity

Falling-edge
polarity

Figure 4-25.

GPCTR0_GATE Signal Timing in Edge-Detection Mode

GPCTR0_OUT Signal

This signal is available only as an output on the GPCTR0_OUT pin.
The GPCTR0_OUT signal reflects the terminal count (TC) of
general-purpose counter 0. You have two software-selectable output
options—pulse on TC and toggle output polarity on TC. The output
polarity is software selectable for both options. This signal is set to

DAQCard E Series User Manual 4-38

t

w

t

= 10 ns minimum

w



National Instruments Corporation

GPCTR0_SOURCE

GPCTR0_OUT

(Pulse on TC)

GPCTR0_OUT

(Toggle output on TC)

Chapter 4 Signal Connections

input (High-Z) at startup. Figure 4-26 shows the timing of the
GPCTR0_OUT signal.

TC

Figure 4-26.

GPCTR0_OUT Signal Timing

GPCTR0_UP_DOWN Signal

This signal can be externally input on the DIO6 pin and is not available
as an output on the I/O connector. The general-purpose counter 0 will
count down when this pin is at a logic low and count up when it is at a
logic high. You can disable this input so that software can control the
up-down functionality and leave the DIO6 pin free for general use.

GPCTR1_SOURCE Signal

Any PFI pin can externally input the GPCTR1_SOURCE signal, which
is available as an output on the PFI3/GPCTR1_SOURCE pin.

As an input, the GPCTR1_SOURCE signal is configured in the
edge-detection mode. You can select any PFI pin as the source for
GPCTR1_SOURCE and configure the polarity selection for either
rising or falling edge.

As an output, the GPCTR1_SOURCE monitors the actual clock
connected to general-purpose counter 1. This is true even if the source
clock is being externally generated by another PFI. This signal is set to
input (High-Z) at startup.



National Instruments Corporation 4-39 DAQCard E Series User Manual

Chapter 4 Signal Connections

Figure 4-27 shows the timing requirements for the GPCTR1_SOURCE
signal.

t

p

t

Figure 4-27.

t

w

w

t

= 50 ns minimum

p

t

= 23 ns minimum

w

GPCTR1_SOURCE Signal Timing

The maximum allowed frequency is 20 MHz, with a minimum pulse
width of 23 ns high or low. There is no minimum frequency limitation.

The 20 MHz or 100 kHz timebase normally generates the
GPCTR1_SOURCE unless you select some external source.

GPCTR1_GATE Signal

Any PFI pin can externally input the GPCTR1_GATE signal, which is
available as an output on the PFI4/GPCTR1_GATE pin.

As an input, the GPCTR1_GATE signal is configured in
edge-detection mode. You can select any PFI pin as the source for
GPCTR1_GATE and configure the polarity selection for either rising
or falling edge. You can use the gate signal in a variety of different
applications to perform such actions as starting and stopping the
counter, generating interrupts, saving the counter contents, and so on.

As an output, the GPCTR1_GATE signal monitors the actual gate
signal connected to general-purpose counter 1. This is true even if the
gate is being externally generated by another PFI. This signal is set to
input (High-Z) at startup.

DAQCard E Series User Manual 4-40



National Instruments Corporation

Chapter 4 Signal Connections

Figure 4-28 shows the timing requirements for the GPCTR1_GATE
signal.

t

w

Rising-edge
polarity

Falling-edge
polarity

t

= 10 ns minimum

w

Figure 4-28.

GPCTR1_OUT Signal

This signal is available only as an output on the GPCTR1_OUT pin.
The GPCTR1_OUT signal monitors the TC board general-purpose
counter 1. You have two software-selectable output options—pulse on
TC and toggle output polarity on TC. The output polarity is software
selectable for both options. This signal is set to input (High-Z) at
startup. Figure 4-29 shows the timing requirements for the
GPCTR1_OUT signal.

GPCTR1_SOURCE

GPCTR1_OUT

(Pulse on TC)

GPCTR1_OUT

(Toggle output on TC)

GPCTR1_GATE Signal Timing in Edge-Detection Mode

Figure 4-29.

TC

GPCTR1_OUT Signal Timing



National Instruments Corporation 4-41 DAQCard E Series User Manual

Chapter 4 Signal Connections

GPCTR1_UP_DOWN Signal

This signal can be externally input on the DIO7 pin and is not available
as an output on the I/O connector. General-purpose counter 1 counts
down when this pin is at a logic low and counts up at a logic high. This
input can be disabled so that software can control the up-down
functionality and leave the DIO7 pin free for general use. Figure 4-30
shows the timing requirements for the GATE and SOURCE input
signals and the timing specifications for the OUT output signals of
your DAQCard.

SOURCE

GATE

OUT

t

sc

V

IH

V

IL

t

gsu

V

IH

V

IL

V

OH

V

OL

Source Clock Period
Source Pulse Width
Gate Setup Time
Gate Hold Time
Gate Pulse Width
Output Delay Time

Figure 4-30.

t

gw

t

out

t 50 ns minimum

sc

t

sp

t

gsu

t

gh

t

gw

t

out

GPCTR Timing Summary

t

sp

t

gh

23 ns minimum
10 ns minimum

0 ns minimum
10 ns minimum
80 ns maximum

t

sp

The GATE and OUT signal transitions shown in Figure 4-30 are
referenced to the rising edge of the SOURCE signal. This timing
diagram assumes that the counters are programmed to count rising
edges. The same timing diagram, but with the source signal inverted
and referenced to the falling edge of the source signal, would apply
when the counter is programmed to count falling edges.

The GATE input timing parameters are referenced to the signal at the
SOURCE input or to one of the internally generated signals on your

DAQCard E Series User Manual 4-42



National Instruments Corporation

Chapter 4 Signal Connections

DAQCard. Figure 4-30 shows the GATE signal referenced to the rising
edge of a source signal. The gate must be valid (either high or low) for
at least 10 ns before the rising or falling edge of a source signal for the
gate to take effect at that source edge, as shown by t

and tgh in

gsu

Figure 4-30. The gate signal is not required to be held after the active
edge of the source signal.

If an internal timebase clock is used, the gate signal cannot be
synchronized with the clock. In this case, gates applied close to a
source edge take effect either on that source edge or on the next one.
This arrangement results in an uncertainty of one source clock period
with respect to unsynchronized gating sources.

The OUT output timing parameters are referenced to the signal at the
SOURCE input or to one of the internally generated clock signals on
the DAQCards. Figure 4-30 shows the OUT signal referenced to the
rising edge of a source signal. Any OUT signal state changes occur
within 80 ns after the rising or falling edge of the source signal.

FREQ_OUT Signal

This signal is available only as an output on the FREQ_OUT pin. The
FREQ_OUT signal is the output of the DAQCard frequency generator.
The frequency generator is a 4-bit counter that can divide its input
clock by the numbers 1 through 16. The input clock of the frequency
generator is software selectable from the internal 10 MHz and 100 kHz
timebases. The output polarity is software selectable. This signal is set
to input (High-Z) at startup.



National Instruments Corporation 4-43 DAQCard E Series User Manual

Chapter 4 Signal Connections

Field Wiring Considerations

Environmental noise can seriously affect the accuracy of
measurements made with your DAQCard if you do not take proper care
when running signal wires between signal sources and the DAQCard.
The following recommendations apply mainly to analog input signal
routing to the DAQCard, although they also apply to signal routing in
general.

You can minimize noise pickup and maximize measurement accuracy
by taking the following precautions:

• Use differential analog input connections to reject common-mode
noise.

• Use individually shielded, twisted-pair wires to connect analog
input signals to the DAQCard. With this type of wire, the signals
attached to the CH+ and CH- inputs are twisted together and then
covered with a shield. You then connect this shield only at one
point to the signal source ground. This kind of connection is
required for signals traveling through areas with large magnetic
fields or high electromagnetic interference.

• Route signals to the DAQCard carefully. Keep cabling away from
noise sources. The most common noise source in a computer data
acquisition system is the video monitor. Separate the monitor from
the analog signals as much as possible.

The following recommendations apply for all signal connections to
your DAQCard:

• Separate DAQCard signal lines from high-current or high-voltage
lines. These lines are capable of inducing currents in or voltages
on the DAQCard signal lines if they run in parallel paths at a close
distance. To reduce the magnetic coupling between lines, separate
them by a reasonable distance if they run in parallel, or run the
lines at right angles to each other.

• Do not run signal lines through conduits that also contain power
lines.

• Protect signal lines from magnetic fields caused by electric
motors, welding equipment, breakers, or transformers by running
them through special metal conduits.

DAQCard E Series User Manual 4-44



National Instruments Corporation

Chapter

Calibration

5

This chapter discusses the calibration procedures for your
DAQCard E Series card. If you are using the NI-DAQ device driver,
that software includes calibration functions for performing all of the
steps in the calibration process.

Calibration refers to the process of minimizing measurement and output
voltage errors by making small circuit adjustments. On the DAQCards,
these adjustments take the form of writing values to onboard calibration
DACs (CalDACs).

Some form of DAQCard calibration is required for all but the most
forgiving applications. If no DAQCard calibration were performed,
your signals and measurements could have very large offset, gain, and
linearity errors.

Three levels of calibration are available to you, and these are described
in this chapter. The first level is the fastest, easiest, and least accurate,
whereas the last level is the slowest, most difficult, and most accurate.

Loading Calibration Constants

Your DAQCard is factory calibrated before shipment at approximately
25° C to the levels indicated in Appendix A,
associated calibration constants—the values that were written to the
CalDACs to achieve calibration in the factory—are stored in the
onboard nonvolatile memory (EEPROM). Because the CalDACs have
no memory capability, they do not retain calibration information when
the DAQCard is unpowered. Loading calibration constants refers to the
process of loading the CalDACs with the values stored in the EEPROM.
NI-DAQ software determines when this is necessary and does it
automatically. If you are not using NI-DAQ, you must load these values
yourself.

In the EEPROM there is a user-modifiable calibration area in addition
to the permanent factory calibration area. This means that you can load



National Instruments Corporation 5-1 DAQCard E Series User Manual

This document was created with FrameMaker 4.0.4

Specifications

. The

Chapter 5 Calibration

the CalDACs with values either from the original factory calibration or
from a calibration that you subsequently performed.

This method of calibration is not very accurate because it does not take
into account the fact that the DAQCard measurement and output voltage
errors can vary with time and temperature. It is better to self-calibrate
when the DAQCard is installed in the environment in which it will be
used.

Self-Calibration

Your DAQCard can measure and correct for almost all of its
calibration-related errors without any external signal connections. Your
National Instruments software provides a self-calibration method you
can use. This self-calibration process, which generally takes less than a
minute, is the preferred method of assuring accuracy in your
application. Initiate self-calibration to minimize the effects of any
offset, gain, and linearity drifts, particularly those due to warmup.

Immediately after self-calibration, the only significant residual
calibration error could be gain error due to time or temperature drift of
the onboard voltage reference. This error is addressed by external
calibration, which is discussed in the following section. If you are
interested primarily in relative measurements, you can ignore a small
amount of gain error, and self-calibration should be sufficient.

External Calibration

Your DAQCard has an onboard calibration reference to ensure the
accuracy of self-calibration. Its specifications are listed in Appendix A,

Specifications

stored in the EEPROM for subsequent self-calibrations. This voltage is
stable enough for most applications, but if you are using your DAQCard
at an extreme temperature or if the onboard reference has not been
measured for a year or more, you may wish to externally calibrate your
DAQCard.

An external calibration refers to calibrating your DAQCard with a
known external reference rather than relying on the onboard reference.
Redetermining the value of the onboard reference is part of this process
and the results can be saved in the EEPROM, so you should not have to

DAQCard E Series User Manual 5-2

. The reference voltage is measured at the factory and



National Instruments Corporation

perform an external calibration very often. You can externally calibrate
your DAQCard by calling the NI-DAQ calibration function.

To externally calibrate your DAQCard, use a very accurate external
reference. The reference should be several times more accurate than the
DAQCard itself. For example, to calibrate a 12-bit DAQCard, the
external reference should be at least ±0.005% (±50 ppm) accurate. To
calibrate a 16-bit DAQCard, the external reference should be at least

±

0.001% (±10 ppm) accurate.

Other Considerations

The CalDACs adjust the gain error of each analog output channel by
adjusting the value of the reference voltage supplied to that channel.
This calibration mechanism is designed to work only with the internal
10 V reference. Thus, in general, it is not possible to calibrate the analog
output gain error when using an external reference. In this case, it is
advisable to account for the nominal gain error of the analog output
channel either in software or with external hardware. See Appendix A,

Specifications

Chapter 5 Calibration

, for analog output gain error information.



National Instruments Corporation 5-3 DAQCard E Series User Manual

Appendix

Specifications

This appendix lists the specifications of each DAQCard in the
DAQCard E Series. These specifications are typical at 25° C unless
otherwise noted.

DAQCard-AI-16E-4

Analog Input

Input Characteristics

Number of channels .......................... 16 single-ended, 16 pseudo-

Type of ADC..................................... Successive approximation

Resolution......................................... 12 bits, 1 in 4,096

Max sampling rate ............................. 250 kS/s guaranteed

A

differential, or 8 differential
(software-selectable on a per
channel basis)



National Instruments Corporation A-1 DAQCard E Series User Manual

This document was created with FrameMaker 4.0.4

Appendix A Specifications for DAQCard-AI-16E-4

Input signal ranges.................

Board Gain

(Software

Selectable)

Board Range

(Software Selectable)

Bipolar Unipolar

0.5

10

20

50

100

±

10 V

1

2

5

±

5 V

±

2.5 V

±

1 V

±

500 mV

±

250 mV

±

100 mV

±

50 mV

—

0 to 10 V

0 to 5 V

0 to 2 V

0 to 1 V

0 to 500 mV

0 to 200 mV

0 to 100 mV

Input coupling................................... DC

Max working voltage

(signal + common mode)................ Each input should remain within

±

11 V of ground

Overvoltage protection......................±25 V powered on, ± 15 V

powered off

Inputs protected ..........................ACH<0..15>, AISENSE

FIFO buffer size................................ 1,024 samples

Data transfers.................................... DMA, interrupt, programmed

I/O

DMA modes...................................... Single transfer, demand transfer

Configuration memory size ............... 512 words

DAQCard E Series User Manual A-2



National Instruments Corporation

Appendix A Specifications for DAQCard-AI-16E-4

Transfer Characteristics

Relative accuracy .............................±0.5 LSB typ dithered, ±1.5 LSB

max undithered

DNL..................................................±0.5 LSB typ, ±1.0 LSB max

No missing codes .............................. 12 bits, guaranteed

Offset error

Pregain error after calibration .....±16 µV max

Pregain error before calibration...±4.0 mV max

Postgain error after calibration ....±1.0 mV max

Postgain error before calibration.±265 mV max

Gain error (relative to calibration reference)

After calibration (gain = 1) .........±0.02% of reading max

Before calibration .......................±2.5% of reading max

Gain ≠ 1 with gain error

adjusted to 0 at gain = 1 .......±0.02% of reading max

Amplifier Characteristics

Input impedance

Normal powered on.....................100 GΩ in parallel with 100 pF

Powered off ................................1 kΩ min

Overload.....................................1 kΩ min

Input bias current ..............................±200 pA

Input offset current ............................±100 pA

CMRR (all input ranges, DC to 60 Hz)

Gain ≤ 1......................................85 dB

Gain = 2......................................95 dB

Gain ≥ 5......................................100 dB

Dynamic Characteristics

Bandwidth

small signal (-3 dB) ....................800 kHz

large signal (1% THD)................400 kHz



National Instruments Corporation A-3 DAQCard E Series User Manual

Appendix A Specifications for DAQCard-AI-16E-4

1,000 h

Settling time for

Gain

Accuracy

full-scale step.....................

±

0.012%

(±0.5 LSB)

0.5 4 µs typ,
8 µs max

System noise in LSB rms,

not including quantization ..........

Gain

0.5 to 10

0.5 to 20 — 0.5

20 0.25 —

50 0.5 0.7

100 0.9 1.0

Noise,

dither off

0.2 —

Crosstalk........................................... -80 dB, DC to 100 kHz

±

0.024%

(±1 LSB)

4 µs max

Noise,

dither on

Stability

Recommended warm-up time............ 15 min

Offset temperature coefficient

Pregain........................................±5 µV/°C

Postgain......................................±240 µV/°C

Gain temperature coefficient .............±20 ppm/°C

Onboard calibration reference

Level...........................................5.000 V (±2.5 mV) (actual value

Temperature coefficient..............±5 ppm/°C max

Long-term stability .....................±15 ppm/

DAQCard E Series User Manual A-4

stored in EEPROM)



National Instruments Corporation

Digital I/O

Appendix A Specifications for DAQCard-AI-16E-4

Number of channels .......................... 8 input/output

Compatibility .................................... TTL/CMOS

Digital logic levels ..........

Level

Min Max

Timing I/O

Input low voltage

Input high voltage 2 V 5 V

Input low current
(V

= 0 V)

in

Input high current
(V

= 5 V)

in

Output low voltage

= 24 mA)

(I

OL

Output high voltage

= 13 mA)

(I

OH

0 V 0.8 V

— -320 µA

— 10 µA

— 0.4 V

4.35 V —

Power-on state................................... Input (High-Z)

Data transfers.................................... Programmed I/O

Number of channels .......................... 2 up/down counter/timers,

1 frequency scaler

Resolution

Counter/timers ............................24 bits

Frequency scalers........................4 bits

Compatibility .................................... TTL/CMOS

Base clocks available

Counter/timers ............................20 MHz, 100 kHz

Frequency scalers........................10 MHz, 100 kHz

Base clock accuracy ..........................±0.01%

Max source frequency ....................... 20 MHz

Min source pulse duration ................. 10 ns in edge-detection mode

Min gate pulse duration..................... 10 ns in edge-detection mode

Data transfers.................................... DMA, interrupts, programmed

I/O

DMA modes...................................... Single transfer



National Instruments Corporation A-5 DAQCard E Series User Manual

Appendix A Specifications for DAQCard-AI-16E-4

Triggers

Analog Trigger

Source............................................... ACH<0..15>, external trigger

Level.................................................± full-scale, internal; ±10 V,

Slope................................................. Positive or negative (software

Resolution......................................... 8 bits, 1 in 256

Hysteresis.......................................... Programmable

Bandwidth (-3 dB)............................. 2.0 MHz internal,

External input (PFI0/TRIG1)

Impedance...................................10 kΩ

Coupling ....................................DC

Protection....................................±35 V powered off,

(PFI0/TRIG1)

external

selectable)

3.0 MHz external

-0.5 to VCC when configured as a
digital signal,

±

35 V when configured as an

analog trigger signal or disabled

Digital Trigger

Compatibility .................................... TTL

Response........................................... Rising or falling edge

Pulse width........................................ 10 ns min

Power Requirement (from PCMCIA I/O channel)

+5 VDC (±5%).................................. 280 mA typ in operational mode,

Power available at I/O connector....... +4.65 to +5.25 V at 250 mA

DAQCard E Series User Manual A-6

400 mA max in operational
mode,
70 mA in power down mode



National Instruments Corporation

Appendix A Specifications for DAQCard-AI-16E-4

Note:

Physical

Environment

These power usage figures do not include the power used by external
devices that are connected to the fused supply present on the I/O connector.

Note also that under ordinary operation, the DAQCard has a current
requirement of 270–290 mA; but if the analog inputs being sampled are
overdriven at high gains, or if the analog inputs are left floating when the
DAQCard is not in use, the current may increase to 400 mA.

You can save current by using the NI-DAQ power down utility when your
DAQCard is not in use.

PC Card type..................................... Type II

I/O connector .................................... PCMCIA 68-position female

connector

Operating temperature....................... 0° to 55° C

Storage temperature........................... -55° to 150° C

Relative humidity.............................. 5% to 90% noncondensing



National Instruments Corporation A-7 DAQCard E Series User Manual

DAQCard-AI-16XE-50

Analog Input

Input Characteristics

Number of channels ...........................16 single-ended or 8 differential

Type of ADC .....................................Successive approximation

Resolution..........................................16 bits, 1 in 65,536

Maximum sampling rate.....................200 kS/s (single-channel),

Input signal ranges.................

(software-selectable)

20 kS/s guaranteed
(scanning; gain = 1, 2, 10),
17 kS/s (scanning; gain = 100)

Board Gain

(Software

Selectable)

Board Range

(Software Selectable)

Bipolar Unipolar

1

2

10

100

±

±

±

±

10 V

5 V

1 V

0.1 V

0 to 10 V

0 to 5 V

0 to 1 V

0 to 0.1 V

Input coupling....................................DC

Maximum working voltage

(signal + common mode) ............ The average voltage of each

differential pair should remain
within ±8 V of ground

Overvoltage protection.......................±25 V powered on, ±15 V

powered off

Inputs protected..........................ACH<0..15>, AISENSE

FIFO buffer size .................................1,024 S

Data transfers.....................................DMA, interrupt, programmed

I/O

DMA modes.......................................Single transfer, demand transfer

Configuration memory size................ 512 words



National Instruments Corporation A-8 DAQCard E Series User Manual

Appendix A Specifications for DAQCard-AI-16XE-50

Transfer Characteristics

Relative accuracy..............................±1.5 LSB typ, ±1.75 LSB max

DNL.................................................. +1.5, -0.75 LSB typ,

+1.75, -1.0 LSB max

No missing codes .............................. 16 bits, guaranteed

Offset error

Pregain error after calibration .....±3 µV max

Pregain error before calibration...±280 µV max

Postgain error after calibration ....±162 µV max (bipolar),

±

81

µ

V max (unipolar)

Postgain error before calibration.±37.5 mV max (bipolar),

±175.75 mV max (unipolar)

Gain error (relative to calibration reference)

After calibration (gain = 1) .........± 7.6 ppm of reading max

Before calibration .......................± 27,650 ppm of reading max

With gain error adjusted to 0 at gain = 1

Gain = 2, 10................................±100 ppm of reading

Gain = 100..................................±250 ppm of reading

Amplifier Characteristics

Input impedance

Normal, powered on....................7 GΩ in parallel with 100 pF

Powered off ................................1 kΩ min

Overload.....................................1 kΩ min

Input bias current .............................. ±10 nA

Input offset current ............................ ±14 nA

CMRR, DC to 60 Hz

Gain = 1......................................80 dB

Gain = 2......................................86 dB

Gain = 10....................................100 dB

Gain = 100..................................120 dB



National Instruments Corporation A-9 DAQCard E Series User Manual

Appendix A Specifications for DAQCard-AI-16XE-50

1,000 h

Dynamic Characteristics

Bandwidth

Gain = 1, 2..................................69 kHz

Gain = 10....................................66 kHz

Gain = 100..................................39 kHz

Settling time for full-scale step

Gain = 1, 2, 10............................50 µs max to ±1 LSB

Gain = 100..................................60 µs max to ±1 LSB

System noise (including quantization noise)

Gain = 1, 2, 10............................1.0 LSB rms

Gain = 100..................................1.2 LSB rms bipolar,

Crosstalk........................................... -85 dB max, DC to 20 kHz

Stability

Recommended warm-up time............ 15 min

Offset temperature coefficient

Pregain........................................± 1 µV/°C

Postgain......................................±120 µV/°C

Gain temperature coefficient ............. ± 15 ppm/°C

Onboard calibration reference

Level................................................. 5.000 V (±2.5 mV) (actual value

Temperature coefficient .................... ± 5 ppm/°C max

Long-term stability............................ ±15 ppm/

50 µs typ to ±4 LSB

1.6 LSB rms unipolar

stored in EEPROM)

DAQCard E Series User Manual A-10



National Instruments Corporation

Digital I/O

Appendix A Specifications for DAQCard-AI-16XE-50

Number of channels .......................... 8 input/output

Compatibility .................................... TTL/CMOS

Timing I/O

Digital logic levels ..........

Level Min Max

Input low voltage 0 V 0.8 V

Input high voltage 2 V 5 V

Input low current — -320 µA

Input high current — 10 µA

Output low voltage
(I

= 24 mA)

OL

Output high voltage
(I

= 13 mA)

OH

— 0.4 V

4.35 V —

Power-on state................................... Input (High-Z) pulled up via

100 kΩ

Data transfers.................................... Programmed I/O

Number of channels .......................... 2 up/down counter/timers,

1 frequency scaler

Resolution

Counter/timers ............................24 bits

Frequency scaler.........................4 bits

Compatibility .................................... TTL/CMOS

Base clocks available

Counter/timers ............................20 MHz, 100 kHz

Frequency scaler.........................10 MHz, 100 kHz

Base clock accuracy .......................... ± 0.01%

Max source frequency ....................... 20 MHz

Min source pulse duration ................ 10 ns, edge-detection mode

Min gate pulse duration .................... 10 ns, edge-detection mode

Data transfers.................................... DMA, interrupts,

programmed I/O



National Instruments Corporation A-11 DAQCard E Series User Manual

Appendix A Specifications for DAQCard-AI-16XE-50

DMA modes...................................... Single transfer, demand transfer

Triggers

Digital Trigger

Compatibility .................................... TTL

Response........................................... Rising or falling edge

Pulse width........................................ 10 ns min

Power Requirement

+5 VDC (±5%).................................. 230 mA active,

Power available at I/O connector....... +4.65 to +5.25 VDC

Note: You can save current by using the NI-DAQ power down utility when your

DAQCard is not in use.

Physical

PC Card type..................................... Type II

I/O connector .................................... PCMCIA 68-position female

90 mA standby

at 250 mA

connector

Environment

Operating temperature....................... 0° to 55° C

Storage temperature........................... -55° to 150° C

Relative humidity.............................. 5% to 90% noncondensing

DAQCard E Series User Manual A-12



National Instruments Corporation

Appendix

Optional Cable Connector
Descriptions

This appendix describes the connectors on the optional cables for the

DAQCard E Series cards.

Figure B-1 shows the pin assignments for the 68-pin AI connector. This

connector is available when you use the PSHR68-68M or PR6868 cable
assemblies with the DAQCard-AI-16E-4 or DAQCard-AI-16XE-50.

B



National Instruments Corporation B-1 DAQCard E Series User Manual

This document was created with FrameMaker 4.0.4

Appendix B Optional Cable Connector Descriptions

ACH8
ACH1

AIGND

ACH10

ACH3

AIGND

ACH4

AIGND

ACH13

ACH6

AIGND

ACH15

Reserved

Reserved

Reserved

DIO4
DGND
DIO1

DIO6
DGND

+5 V
DGND
DGND

PFI0/TRIG1
PFI1/TRIG2

DGND

+5 V
DGND

PFI5/UPDATE*

PFI6/WFTRIG

DGND

PFI9/GPCTR0_GATE

GPCTR0_OUT

FREQ_OUT






34 68
33 67
32 66
31 65
30 64
29 63
28 62
27 61
26 60
25 59
24 58
23 57
22 56
21 55
20 54
19 53
18 52
17 51
16 50
15 49
14 48
13 47
12 46
11 45
10 44

943
842
741
640
539
438
337
236
135

ACH0
AIGND
ACH9
ACH2
AIGND
ACH11
AISENSE
ACH12
ACH5
AIGND
ACH14
ACH7
Reserved
Reserved
Reserved
DGND
DIO0

DIO5
DGND

DIO2
DIO7
DIO3
SCANCLK
EXTSTROBE*
DGND
PFI2/CONVERT*
PFI3/GPCTR1_SOURCE
PFI4/GPCTR1_GATE
GPCTR1_OUT
DGND
PFI7/STARTSCAN
PFI8/GPCTR0_SOURCE
DGND
DGND

Figure B-1.

68-Pin AI Connector Pin Assignments

DAQCard E Series User Manual B-2



National Instruments Corporation

Appendix B Optional Cable Connector Descriptions

Figure B-2 shows the pin assignments for the 50-pin AI connector. This
connector is available when you use the SH6850 or R6850 cable
assemblies with the PSHR68-68M.

AIGND

ACH0
ACH1

ACH2

ACH3

ACH4
ACH5
ACH6

ACH7
AISENSE
Reserved
Reserved

DIO0
DIO1
DIO2
DIO3

DGND

+5 V

EXTSTROBE*

PFI1/TRIG2

PFI3/GPCTR1_SOURCE

GPCTR1_OUT

PFI6/WFTRIG

PFI8/GPCTR0_SOURCE

GPCTR0_OUT

12
34
56
78

910
11 12
13 14
15 16
17 18
19 20
21 22
23 24
25 26
27 28
29 30
31 32
33 34
35 36
37 38
39 40
41 42
43 44
45 46
47 48
49 50

AIGND
ACH8
ACH9
ACH10
ACH11
ACH12
ACH13
ACH14

ACH15
Reserved

Reserved
DGND
DIO4
DIO5
DIO6
DIO7
+5 V
SCANCLK
PFI0/TRIG1
PFI2/CONVERT*
PFI4/GPCTR1_GATE
PFI5/UPDATE*
PFI7/STARTSCAN
PFI9/GPCTR0_GATE
FREQ_OUT

Figure B-2.

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National Instruments Corporation B-3 DAQCard E Series User Manual

50-Pin AI Connector Pin Assignments

Appendix

PC Card Questions and
Answers

Note:

Configuration

1. Do I need to use my PCMCIA configuration utility to configure the National
Instruments PC Cards?

If you are using Windows 95, the operation system will automatically
configure your PC Card. All questions in this appendix are specific to
Windows 3.1, with the exception of question 3 in the

C

This appendix contains a list of common questions and answers relating
to PC Card (PCMCIA) operation. The questions are grouped according
to the type of information requested. You may find this information
useful if you are having difficulty with the PCMCIA system software
configuration and you are using Windows 3.1.

Operation

No. We recommend that you do not configure our PC Cards using PC

Card Control or an equivalent PC Card configuration utility. Use the

configuration utilities included with the NI-DAQ driver software to

properly configure your DAQCard. The appropriate utility is the

NI-DAQ Configuration Utility (

WDAQCONF)

for Windows 3.1 users.

section.

2. What should I do if my computer does not have Card and Socket Services
version 2.0 or later?

Contact the manufacturer of your computer or of your PCMCIA adapter
and request the latest Card and Socket PCMCIA driver. Our NI-DAQ
software will work with any Card and Socket Service driver that is
compliant to version 2.0 or higher.

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National Instruments Corporation C-1 DAQCard E Series User Manual

This document was created with FrameMaker 4.0.4

Appendix C PC Card Questions and Answers

Operation

1. My PC Card works when inserted before power-on time, but it does not work
when hot inserted. What is wrong?

You may have an interrupt conflict. If you have a utility such as

MSD.EXE

question 5 in the
Microsoft Windows.

2. My computer locks up when I use a PC Card. What should I do?

This usually happens because Card Services allocated an unusable
interrupt level to the PC Card. For example, on some computers,
interrupt level 11 is not routed to PC Cards. If Card Services is not
aware of this, it may assign interrupt 11 to a PC Card even though the
interrupt is not usable. When a call uses the interrupt, the interrupt
never occurs, and the computer locks up waiting for a response. For
information about how to locate an interrupt that is free to be used, refer
to question 4 in the

, run it to determine the allocated interrupts, then refer to

Resources

Resources

section.

section.

MSD.EXE

is usually shipped with

3. Is there a way I can conserve power on my PC Card when it is not in use?

Yes. If you are using NI-DAQ for PC compatibles version 4.8.0 or later,
a utility called
Cards between normal mode and power-down mode. Run
from the command line to view instructions on the proper usage. Refer
to Appendix E,
these modes.

DAQPOWER.EXE

Power-Management Modes

Resources

1. How do I determine if I have a memory conflict?

If no PC Cards are working at all, it is probably because a memory
window is not usable. Card Services uses a 4 kB memory window for
its own internal use. If the memory cannot be used, then Card Services
cannot read the Card Information Structure (CIS) from the DAQCard
EPROM, which means it cannot identify cards.

There are two different methods you can use when Card Services has a
problem reading the CIS. First, you can determine which memory
window Card Services is using, and then exclude that window from use

DAQCard E Series User Manual C-2

will switch National Instruments PC

DAQPOWER

, for more information on

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National Instruments Corporation