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National Instruments DAQCard-1200 Single-Ended Connection Considerations, Single-Ended Connections for Floating Signal Sources (RSE Configuration)

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Chapter 3 Signal Connections

© National Instruments Corporation 3-11 DAQCard-1200 User Manual

Single-Ended Connection Considerations

Single-ended connections are those in which all DAQCard-1200 analog

input signals are referenced to one common ground. The input signals are

tied to the positive input of the instrumentation amplifier, and their

common ground point is tied to the negative input of the instrumentation

amplifier.

When the DAQCard-1200 is configured for single-ended input (NRSE or

RSE), eight analog input channels are available. You can use single-ended

input connections when the following criteria are met by all input signals:

• Input signals are high level (greater than 1 V).

• Leads connecting the signals to the DAQCard-1200 are less than 15 ft.

• All input signals share a common reference signal (at the source).

If any of the preceding criteria is not met, you should use DIFF input

configuration.

You can software configure the DAQCard-1200 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-1200 provides the reference ground point for the external signal.

Use the NRSE configuration for ground-referenced signal sources; in this

case, the external signal supplies its own reference ground point and the

DAQCard-1200 should not supply one.

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

Figure3-5 shows how to connect a floating signal source to a

DAQCard-1200 configured for single-ended input. You must configure the

DAQCard-1200 analog input circuitry for RSE input to make these types

of connections. For configuration instructions, refer to the Analog Input

Configuration section of Chapter 2, Installation and Configuration.

Contents

Main Page Important Information Warranty Copyright Trademarks WARNING REGARDING USE OF NATIONAL INSTRUMENTS PRODUCTS Contents Chapter 4 Theory of Operation Page Tables About This Manual Organization of This Manual Conventions Used in This Manual National Instruments Documentation Related Documentation Introduction About the DAQCard-1200 What You Need to Get Started Software Programming Choices LabVIEW and LabWindows/CVI Application Software NI-DAQ Driver Software Register-Level Programming Optional Equipment Unpacking Installation and Configuration Installation Configuration Analog Input Configuration Analog Input Polarity Analog Input Mode RSE Input (Eight Channels, Default Setting) NRSE Input (Eight Channels) DIFF Input (Four Channels) Analog Output Configuration Analog Output Polarity Digital I/O Configuration Counter Configuration Signal Connections I/O Connector Figure 3-1. DAQCard-1200 I/O Connector Pin Assignments Signal Connection Descriptions Analog Input Signal Connections + Types of Signal Sources Floating Signal Sources Ground-Referenced Signal Sources Input Configurations Differential Connection Considerations (DIFF Configuration) Differential Connections for Grounded Signal Sources Figure 3-3. Differential Input Connections for Grounded Signal Sources Differential Connections for Floating Signal Sources Figure 3-4. Differential Input Connections for Floating Sources Single-Ended Connection Considerations Single-Ended Connections for Floating Signal Sources (RSE Configuration) Single-Ended Connections for Grounded Signal Sources (NRSE Configuration) Common-Mode Signal Rejection Considerations Analog Output Signal Connections Digital I/O Signal Connections Page Port C Pin Connections Timing Specifications Mode 1 Input Timing Mode 1 Output Timing Mode 2 Bidirectional Timing Page DAQ and General-Purpose Timing Signal Connections DAQ Timing Connections Page Page Page General-Purpose Timing Signal Connections Page Page Figure 3-18. Frequency Measurement Application Chapter 3 Signal Connections DAQCard-1200 User Manual 3-30 National Instruments Corporation Figure 3-19. General-Purpose Timing Signals The GATE and OUT signals in Figure3-19 are referenced to the rising edge of the CLK signal. Power Connections National Instruments Corporation 4-1 DAQCard-1200 User Manual Theory of Operation This chapter explains the operation of each functional unit of the DAQCard-1200. Figure 4-1. DAQCard-1200 Block Diagram Functional Overview The block diagram in Figure 4-1 shows a functional overview of the DAQCard-1200. PC Card I/O Channel Interface Circuitry Timing Chapter 4 Theory of Operation Figure 4-3. Timing Circuitry DAQCard-1200 User Manual 4-4 National Instruments Corporation Analog Input Analog Input Circuitry Page Data Acquisition Timing Data Acquisition Operation Continuous Data Acquisition Interval Data Acquisition Data Acquisition Rates Page Analog Output Analog Output Circuitry Power-On State DAC Timing Digital I/O Calibration Calibration at Higher Gains Calibration Equipment Requirements Using the Calibration Function Page A Specifications Analog Input Input Characteristics Transfer Characteristics Amplifier Characteristics Dynamic Characteristics Stability Analog Output Output Characteristics Transfer Characteristics Page Timing I/O Digital Trigger Bus Interface Power Requirement Physical Page B Differences among the Lab-PC+, the DAQPad-1200, and the DAQCard-1200 Page C Power-Management Modes Page D PC Card Questions and Answers Configuration Operation Resources Page Page E Technical Support Resources NI Web Support Online Problem-Solving and Diagnostic Resources Software-Related Resources Worldwide Support Glossary Numbers/Symbols A B C D E F G Page Page V Index Numbers A B C D E F G I L M N O R S T U V W