National Instruments SC-207 Series User manual

SC-2052

© Copyright 1991, 1995 National Instruments Corporation.
All Rights Reserved.
SC-207X Series
User Manual
General-Purpose Termination Breadboards
November 1995 Edition
Part Number 371173A-01

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Limited Warranty
The SC-207X Series boards 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.
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.
EXCEPT AS SPECIFIED HEREIN, NATIONAL INSTRUMENTS MAKES NO WARRANTIES, EXPRESS OR
IMPLIED, AND SPECIFICALLY DISCLAIMS ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR
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including negligence. Any action against National Instrument 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.
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Product and company names listed are trademarks or trade names of their respective companies.

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
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National Instruments products for or involving medical or clinical treatment must be performed by properly
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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.

© National Instruments Corporation v SC-207X Series User Manual
Contents
About This Manual ............................................................................................................ xi
Organization of This Manual.........................................................................................xi
Conventions Used in This Manual.................................................................................xii
Related Documentation..................................................................................................xii
Customer Communication .............................................................................................xiii
Chapter 1
Introduction ......................................................................................................................... 1-1
About the SC-207X Series Boards.................................................................................1-1
What You Need to Get Started ......................................................................................1-4
Optional Equipment.......................................................................................................1-4
Software .........................................................................................................................1-4
Unpacking......................................................................................................................1-5
Chapter 2
SC-2070 Board .................................................................................................................... 2-1
Analog Input ..................................................................................................................2-2
Temperature Sensor .......................................................................................................2-3
Shield Ground ................................................................................................................2-4
Fuse and Power LED .....................................................................................................2-4
Digital and Timing Signals ............................................................................................2-4
Board-to-Board Cabling.................................................................................................2-5
Mounting........................................................................................................................2-6
Applications ...................................................................................................................2-6
Soldering and Desoldering on the SC-2070 Board............................................2-7
Channel Configurations .....................................................................................2-7
Connecting Nonreferenced or Floating Signal Sources.....................................2-7
Differential Inputs..................................................................................2-7
Single-Ended Inputs...............................................................................2-8
Connecting Ground-Referenced Signal Sources................................................2-9
Differential Inputs..................................................................................2-9
Single-Ended Inputs...............................................................................2-9
Building Lowpass Filters ...................................................................................2-10
Building Highpass Filters...................................................................................2-13
Building Attenuators (Voltage Dividers)...........................................................2-15
Working with Thermocouples .......................................................................................2-17
Using the SC-2070 Board for Thermocouple Measurements........................................2-17
Input Filtering and Broken Thermocouple Detection (Optional) ......................2-18
Selecting the Gain and Input Ranges.................................................................2-19
Linearizing the Data...........................................................................................2-20

Contents
SC-207X Series User Manual vi © National Instruments Corporation
Differential Measurements.................................................................................2-22
An Example of Using Thermocouples in Differential Mode.............................2-22
Single-Ended Measurements..............................................................................2-23
An Example of Using Thermocouples in Single-Ended Mode..........................2-23
Sources of Error .................................................................................................2-24
Thermocouple Measurement Accuracies...........................................................2-25
Additional Signal Connection Information....................................................................2-25
Chapter 3
SC-2071 Board .................................................................................................................... 3-1
Analog Input ..................................................................................................................3-2
Temperature Sensor .......................................................................................................3-4
Shield Ground ................................................................................................................3-4
Fuse and Power LED .....................................................................................................3-4
Digital and Timing Signals ............................................................................................3-5
Board-to-Board Cabling.................................................................................................3-5
Mounting........................................................................................................................3-7
Applications ...................................................................................................................3-7
Soldering and Desoldering on the SC-2071 Board............................................3-7
Connecting Floating Signal Sources..................................................................3-8
Connecting Grounded Signal Sources ...............................................................3-8
Building Lowpass Filters ...................................................................................3-8
Building Highpass Filters...................................................................................3-10
Building Attenuators (Voltage Dividers)...........................................................3-12
Working with Thermocouples .......................................................................................3-14
Using the SC-2071 Board for Thermocouple Measurements........................................3-15
Input Filtering and Broken Thermocouple Detection (Optional) ......................3-15
Selecting the Gain and Input Ranges.................................................................3-16
Linearizing the Data...........................................................................................3-17
Measurement Connections.................................................................................3-18
An Example of Using Thermocouples...............................................................3-19
Sources of Error .................................................................................................3-19
Thermocouple Measurement Accuracies...........................................................3-20
Additional Signal Connection Information....................................................................3-21
Chapter 4
SC-2072 Board .................................................................................................................... 4-1
Signal Connections ........................................................................................................4-3
Power Connections ........................................................................................................4-4
Fuses and Power LED....................................................................................................4-5
Board-to-Board Cabling.................................................................................................4-6
Mounting........................................................................................................................4-7
Soldering and Desoldering on the SC-2072 Board........................................................4-7

Contents
© National Instruments Corporation vii SC-207X Series User Manual
Chapter 5
Installation and Connections .......................................................................................... 5-1
Hardware Installation.....................................................................................................5-1
Hardware Installation for the SC-2070 and the SC-2071 ..................................5-1
Hardware Installation for the SC-2072 ..............................................................5-2
Installing the SC-205X Series Cable Adapter Boards .......................................5-2
Installing the BNC-2081 Analog Breakout Board.............................................5-3
Rack Mounting...................................................................................................5-3
External Power Connection (If Necessary)........................................................5-4
SC-207X Series Board Connection....................................................................5-7
Signal Connections ........................................................................................................5-8
Ribbon Cable Connectors ..................................................................................5-8
Screw Terminal Connections for the SC-2070 and the SC-2071 ......................5-8
Screw Terminal Connections for the SC-2072 ..................................................5-9
Rack-Mount Chassis Cover Attachment............................................................5-9
Appendix A
Specifications........................................................................................................................ A-1
Appendix B
Customer Communication............................................................................................... B-1
Glossary......................................................................................................................Glossary-1
Index .................................................................................................................................Index-1

Contents
SC-207X Series User Manual viii © National Instruments Corporation
Figures
Figure 1-1. SC-2070 Board Connected Directly to an MIO-16 Board................................. 1-3
Figure 1-2. SC-207X Series Board, SC-206X Series Board, and SC-205X Series Board
Connected to an MIO-16 Board......................................................................... 1-3
Figure 2-1. SC-2070 Board Parts Locator Diagram ............................................................. 2-2
Figure 2-2 Onboard Equivalent Circuit ............................................................................... 2-3
Figure 2-3. W1 Jumper Settings ........................................................................................... 2-4
Figure 2-4. W2 Jumper Settings ...........................................................................................2-4
Figure 2-5. Direct Connection between an MIO-16 Board and the SC-2070 Board ...........2-5
Figure 2-6. Connection between an MIO-16 Board and the SC-2070 Board via the
SC-2050 Board...................................................................................................2-6
Figure 2-7. Bias Return Resistor for DC-Coupled Floating Source on Channel 1...............2-8
Figure 2-8. Normalized Frequency Response of Lowpass Filter ......................................... 2-10
Figure 2-9. Lowpass Filter on Differential Channel 1.......................................................... 2-12
Figure 2-10. Normalized Frequency Response of Highpass Filter......................................... 2-13
Figure 2-11. Highpass Filter on Differential Channel 1......................................................... 2-14
Figure 2-12. Attenuator for Use with Differential Inputs....................................................... 2-16
Figure 2-13. Thermocouple Circuit with Open Thermocouple Detect and Lowpass
Noise Filter.........................................................................................................2-19
Figure 3-1. SC-2071 Board Parts Locator Diagram .............................................................3-2
Figure 3-2. Onboard Equivalent Circuit ...............................................................................3-3
Figure 3-3. W1 Jumper Settings ...........................................................................................3-4
Figure 3-4. W2 Jumper Settings ...........................................................................................3-4
Figure 3-5. Direct Connection between a Lab/1200 Device and the SC-2071 Board..........3-5
Figure 3-6. Daisy-chaining a Lab/1200 Device to a BNC-2081 ..........................................3-6
Figure 3-7. Connection between a Lab/1200 Device and the SC-2071 Board via the
SC-2053 Board...................................................................................................3-6
Figure 3-8. Normalized Frequency Response of Lowpass Filter ......................................... 3-9
Figure 3-9. Lowpass Filter on Channel 1 ............................................................................. 3-10
Figure 3-10. Normalized Frequency Response of Highpass Filter......................................... 3-11
Figure 3-11. Highpass Filter on Channel 1............................................................................. 3-12
Figure 3-12. Attenuator for Use with SC-2071 Board Inputs................................................. 3-13
Figure 3-13. Thermocouple Circuit with Open Thermocouple Detect and Lowpass
Noise Filter.........................................................................................................3-16
Figure 4-1. SC-2072 Board Parts Locator Diagram .............................................................4-2
Figure 4-2. SC-2072D Board Parts Locator Diagram ..........................................................4-3
Figure 4-3. Direct Connection between a TIO-10 Board and the SC-2072 Board...............4-6
Figure 4-4. Connection between a DIO-24 Board and the SC-2072 Board via the
SC-2051 Board...................................................................................................4-6
Figure 5-1. Mounting Locations for SC-207X Series Boards ..............................................5-3
Figure 5-2. Attaching a Mountable Board to the Chassis.....................................................5-3
Figure 5-3. Double-Height Mounting...................................................................................5-4
Figure 5-4. Connections Between DAQ Devices and SC-205X Series
Boards and Between SC-205X Series Boards and SC-2070
and SC-2071 Boards ..........................................................................................5-7

Contents
© National Instruments Corporation ix SC-207X Series User Manual
Tables
Table 1-1. DAQ Devices for Use with SC-207X Series Boards......................................... 1-2
Table 2-1. Component Positions in Each Channel..............................................................2-3
Table 2-2. DAQ Boards Used with the SC-2070 Board .....................................................2-5
Table 2-3. Thermocouple Voltage Output Extremes (mV).................................................2-20
Table 2-4. NBS Polynomial Coefficients............................................................................2-21
Table 2-5. Thermocouple Measurement Accuracies...........................................................2-25
Table 3-1. Component Positions in Each Channel..............................................................3-3
Table 3-2. DAQ Devices Used with the SC-2071 Board....................................................3-5
Table 3-3. Thermocouple Voltage Output Extremes (mV).................................................3-17
Table 3-4. NBS Polynomial Coefficients............................................................................3-18
Table 3-5. Thermocouple Measurement Accuracies...........................................................3-21
Table 4-1. Switch S2 Settings for National Instruments DAQ Devices.............................. 4-4
Table 5-1. Amount of Power Supplied by DAQ Devices ...................................................5-6
Table 5-2. SC-205X Series Board Connectors Compatible with the SC-207X
Series Boards......................................................................................................5-8

© National Instruments Corporation xi SC-207X Series User Manual
About This Manual
This manual describes the mechanical and electrical aspects of the SC-2070, SC-2071, and
SC-2072 boards and contains information about installing and making connections to the boards.
The SC-207X Series boards are general-purpose termination breadboards. These breadboards
connect to the National Instruments multifunction data acquisition (DAQ) boards for the
IBM PC/XT/AT, Personal System/2, and compatible computers, and Macintosh II computers.
Each of the SC-207X Series boards is described in detail in this manual.
Organization of This Manual
The SC-207X Series User Manual is organized as follows:
• Chapter 1, Introduction, describes the SC-207X Series boards, lists what you need to get
started, describes the optional equipment and software, and explains how to unpack your
SC-207X Series board.
• Chapter 2, SC-2070 Board, describes the SC-2070 board in detail, including function,
compatibility, connection, mounting, and applications. This chapter also discusses working
with thermocouples.
• Chapter 3, SC-2071 Board, describes the SC-2071 board in detail, including function,
compatibility, connection, mounting, and applications. This chapter also discusses working
with thermocouples.
• Chapter 4, SC-2072 Board, describes the SC-2072 board in detail, including function,
connection, mounting, and soldering/desoldering.
• Chapter 5, Installation and Connections, explains how to install and make connections to the
SC-207X Series boards.
• Appendix A, Specifications, contains specifications for the SC-207X Series boards.
• Appendix B, Customer Communication, contains forms you can use to request help from
National Instruments or to comment on our products.
• The Glossary contains an alphabetical list and description of terms used in this manual,
including abbreviations, acronyms, metric prefixes, and symbols.
• The Index alphabetically list the topics in the manual, including the page where you can find
each one.

About This Manual
SC-207X Series User Manual xii © National Instruments Corporation
Conventions Used in This Manual
The following conventions are used in this manual:
bold Bold text denotes menus, menu items, or dialog box buttons or options.
bold italic Bold italic text denotes a note, caution, or warning.
italic Italic text denotes emphasis, a cross reference, or an introduction to a key
concept.
monospace Text in this font is used for function names.
SC-206X Series SC-206X Series refers to SC-2060, SC-2061, or SC-2062 boards.
DIO board DIO board refers to the NB-DIO-24, NB-DIO-32F, NB-DIO-96,
MC-DIO-24, MC-DIO-32F, PC-DIO-24, AT-DIO-32F, and PC-DIO-96
boards.
DIO-24 DIO-24 refers to the NB-DIO-24, MC-DIO-24, and PC-DIO-24 boards.
DIO-32F DIO-32F refers to the NB-DIO-32F, MC-DIO-32F, and AT-DIO-32F
boards.
Lab/1200 Series Lab/1200 Series refers to the Lab-LC, Lab-NB, Lab-PC, and Lab-PC+
boards, and the DAQCard-1200, DAQPad-1200, and PCI-1200 devices.
MIO-16 MIO-16 refers to the NB-MIO-16, NB-MIO-16X, MC-MIO-16,
AT-MIO-16, AT-MIO-16D, AT-MIO-16F-5, and AT-MIO-16X boards.
NI-DAQ NI-DAQ refers to the NI-DAQ software for PC compatibles or Macintosh
unless otherwise stated.
TIO-10 TIO-10 refers to the PC-TIO-10 board.
Abbreviations, acronyms, metric prefixes, and symbols are listed in the Glossary.
Related Documentation
The following National Instruments documents contain information that you may find helpful as
you read this manual:
• Your DAQ hardware manuals
•BNC-208X Series User Manual
•SC-205X User Manual

About This Manual
© National Instruments Corporation xiii SC-207X Series User Manual
•SC-206X User Manual
• National Instruments Application Note 043, Measuring Temperature with Thermocouples.
• NIST Monograph 175, Temperature-Electromotive Force Reference Functions and Tables
for the Letter-Designated Thermocouple Types Based on the ITS-90 (National Institute of
Standards and Technology, Gaithersburg, MD 20899).
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 B, Customer
Communication, at the end of this manual.

© National Instruments Corporation 1-1 SC-207X Series User Manual
Chapter 1
Introduction
About the SC-207X Series Boards
This chapter describes the SC-207X Series boards, lists what you need to get started, describes
the optional equipment and software, and explains how to unpack your SC-207X Series board.
The SC-2070 and SC-2071 boards are two general-purpose breadboards with signal-labeled
screw terminals and temperature sensor, breadboard, and analog signal conditioning areas. The
SC-2070 and SC-2071 boards can be used for analog signal conditioning on the Macintosh,
IBM PS/2 Micro Channel, and IBM PC/XT/AT computers. The SC-2070 and SC-2071
breadboards simplify the connection of analog and digital signals to the DAQ board in
laboratory, test, and production environments. Up to seven thermocouples can be connected to
each SC-2070 or SC-2071 board while using one channel to monitor the onboard temperature
sensor for cold-junction compensation. The temperature sensor can be disconnected to make all
eight differential or 16 single-ended analog input channels available on the board. The boards
have silkscreened component locations for resistors and capacitors for building single-pole
highpass and lowpass filters, voltage dividers, and broken thermocouple detectors. The SC-2070
and SC-2071 boards also have a general-purpose breadboard area for building custom analog,
digital, and timing circuits.
The SC-2072 board is a general-purpose breadboard with screw terminals and a breadboard area
that can be used for building custom analog, digital, and timing circuits. The SC-2072 can be
used with all National Instruments NB Series, MC Series, PC Series, AT Series,
Lab/1200 Series, and the PC-OPDIO-16 DAQ, digital I/O, and timing boards (except the
NB-A2000 and the EISA-A2000), and some DAQCards. The board comes with an optional
DC-to-DC converter that converts the +5 V input into +15 V and-15 V for use by analog
circuitry.
Detailed specifications of the SC-207X boards are in Appendix A, Specifications.

Introduction Chapter 1
SC-207X Series User Manual 1-2 © National Instruments Corporation
Table 1-1 lists the specific DAQ devices that can currently be used with the SC-207X Series
boards.
Table 1-1. DAQ Devices for Use with SC-207X Series Boards
NB Series
(Macintosh)
MC Series
(IBM PS/2)
PC and AT
Series
(PC/XT/AT)
Lab/1200 Series
(PC/XT/AT and
Macintosh)
Other
Devices
SC-2070 NB-MIO-16,
NB-MIO-16X
MC-MIO-16 AT-MIO-16,
AT-MIO-16D1,
AT-MIO-16F-5,
AT-MIO-16X,
AT-MIO-64F-51
SC-2071 Lab-LC2,
Lab-NB,
Lab-PC+,
DAQCard-12003,
DAQPad-1200,
PCI-1200
SC-2072 NB-DIO-24,
NB-DIO-32F,
NB-MIO-16,
NB-MIO-16X
MC-DIO-24,
MC-DIO-32F,
MC-MIO-16
AT-DIO-32F,
AT-MIO-16,
AT-MIO-16D1,
AT-MIO-16F-5,
AT-MIO-16X,
PC-DIO-24,
PC-DIO-96,
PC-LPM-16,
PC-TIO-10
Lab-LC2,
Lab-NB,
Lab-PC+,
DAQCard-1200,
DAQPad-1200,
PCI-1200
DAQCard-700,
DAQCard-DIO-24,
PC-OPDIO-16
1Requires an NB5 cable, available separately. 3Requires a PR50-50F cable, available separately.
2Requires an NB10 cable, available separately.
All the signals from the DAQ board, both analog and digital, are made available at screw
terminals. Each of the SC-207X Series boards is connected directly to the DAQ board by a
50-pin ribbon cable. If any SC-206X Series digital signal conditioning boards are also being
used with the same DAQ board for conditioning of the digital I/O signals, then an SC-205X
Series cable adapter board is required. Figure 1-1 shows the SC-2070 board, mounted in a 19-in.
rack mount, directly connected to the MIO-16 board.

Introduction Chapter 1
SC-207X Series User Manual 1-4 © National Instruments Corporation
What You Need to Get Started
To set up and use your SC-207X board, you will need the following:
SC-2070, SC-2071, SC-2072, or SC-2072D board
SC-207X Series User Manual
50-conductor NB1 0.5 or 1.0 m cable (some kits do not contain either cable)
Your computer
Optional Equipment
You can use the following National Instruments products with your SC-207X Series board:
• Type NB5 ribbon cable, 0.5 or 1.0 m
• Type NB10 cable
• Rack-mount chassis kit with acrylic plastic cover, single or double height
• Rack-mount chassis kit with metal wraparound cover, single or double height
• SSR Series eight-channel backplane with 0.4 m cable for SC-2050 Series
• SC-2060 and 26-conductor cable, 0.2 or 0.4 m
• SC-2061 and 26-conductor cable, 0.2 or 0.4 m
• SC-2062 and 26-conductor cable, 0.2 or 0.4 m
• SC-2050 and 50-conductor cable, 0.5 or 1.0 m
• SC-2051 and 50-conductor cable, 0.5 or 1.0 m
• SC-2052 and 50-conductor cable, 0.5 or 1.0 m
• SC-2053 and 50-conductor cable, 0.5 or 1.0 m
• PR50-50F cable
Software
The SC-207X Series boards require no additional software support beyond what you are using
for your DAQ device.

Chapter 1 Introduction
© National Instruments Corporation 1-5 SC-207X Series User Manual
Unpacking
Your SC-207X board is shipped in an antistatic package to prevent electrostatic damage to the
board. Electrostatic discharge can damage several components on the board. To avoid such
damage in handling the board, take the following precautions:
• Ground yourself via a grounding strap or by holding a grounded object.
• Touch the antistatic package to a metal part of your computer chassis before removing the
board from the package.
• Remove the board from the package and inspect the board for loose components or any other
sign of damage. Notify National Instruments if the board appears damaged in any way.
Do not install a damaged board into your computer.
•Never touch the exposed pins of connectors.

© National Instruments Corporation 2-1 SC-207X Series User Manual
Chapter 2
SC-2070 Board
This chapter describes the SC-2070 board in detail, including function, compatibility, connection,
mounting, and applications. This chapter also discusses working with thermocouples.
The SC-2070 is a general-purpose termination breadboard that makes it easy to connect to all MIO-16
board I/O signals; add analog input signal conditioning, such as filters, dividers, and thermocouple
compensation; and build external, custom timing, analog, and digital circuits.
The SC-2070 board is used with National Instruments DAQ boards for the Macintosh (NB Series),
IBM PS/2 Micro Channel (MC Series), and PC/XT/AT and compatible (AT Series) computers.
The SC-2070 board has screw terminals for all DAQ board signals. With these terminals, the board
easily connects to the analog, digital, timing, and trigger signals. The SC-2070 has an onboard
temperature sensor that can be optionally jumpered to differential channel 0 for thermocouple cold-
junction compensation. With open component positions in the input paths, you can insert resistors and
capacitors for conditioning the 16 single-ended or 8 differential analog input signals. A 1.5 by 4 in.
general-purpose breadboard area is also included. The SC-207X Series boards can also be used in
conjunction with the other signal conditioning accessories, including the SC-206X Series boards and
SSR Series boards. To connect multiple signal conditioning accessories, you must use an SC-205X
Series cable adapter board.

SC-2070 Board Chapter 2
SC-207X Series User Manual 2-2 © National Instruments Corporation
Figure 2-1 shows the parts locator diagram for the SC-2070 board.
1
2
3 4
56
1 50-pin I/O Connector 4 General-Purpose Breadboard Area
2 Temperature Sensor Selection 5 Fuse
3 Temperature Sensor 6 Shield Ground Selection
Figure 2-1. SC-2070 Board Parts Locator Diagram
Analog Input
Each differential analog input has seven open positions for signal conditioning components. Six of
these positions are designated as resistors, and one is designated as a capacitor. The board is shipped
with jumpers in two positions for each input. The equivalent circuit of one input is shown in
Figure 2-2. The board can be used when the MIO-16 board is configured for both 16 single-ended
inputs and eight differential inputs. For thermocouple and other low-level applications, best results are
obtained when differential inputs are used. For specific applications illustrating signal conditioning
with both single-ended and differential inputs, refer to Applications later in this chapter.