National Instruments NI 783xR - page 24

Chapter 2 Hardware Overview ofthe NI 783xR

© National Instruments Corporation 2-5 NI 783xR User Manual

Figure 2-3. NI783xR Instrumentation Amplifier

The instrumentation amplifier applies common-mode voltage rejection

and presents high input impedance to the AI signals connected to the

NI7 83xR. Input multiplexers on the device route signals to the positive and

negative inputs of theinstrumentation amplifier. The instrumentation

amplifier converts two input signals to a signal that is the difference

between the two input signals. The amplifier output voltage is referenced to

the device ground. The NI783xR ADC measures this output voltage when

it performs A/D conversions.

You must reference all signals to ground either at the source device or at the

NI7 83xR. If you have a floating source, reference the signal to ground by

using RSE input mode or the DIFF input mode with bias resistors. Refer to

the Differential Connections for Nonreferenced or Floating Signal Sources

section of this chapter for more information about these input modes. If you

have a grounded source, do not reference the signal to AIGND. You can

avoid this reference by using DIFF or NRSE input modes.

+

+

–

–

Vm = [Vin+ – Vin–]

Vin+

Vin–

Vm

Instrumentation

Amplifier

Measured

Voltage

Contents

Main Page Important Information Warranty Copyright Trademarks Patents Compliance Compliance with FCC/Canada Radio Frequency Interference Regulations Determining FCC Class FCC/DOC Warnings Class A Contents About This Manual Chapter 1 Introduction Chapter 2 Hardware Overview of the NI 783xR Page About This Manual Conventions Reconfigurable I/O Documentation Related Documentation Introduction About the NI 783xR Using PXI with CompactPCI Overview of Reconfigurable I/O Reconfigurable I/O Concept Flexible Functionality User-Defined I/O Resources Device-Embedded Logic and Processing Reconfigurable I/O Architecture Reconfigurable I/O Applications Software Development LabVIEW FPGA Module LabVIEW Real-Time Module Cables and Optional Equipment Custom Cabling Safety Information Page National Instruments Corporation 2-1 NI 783xR User Manual Hardware Overview of the NI 783xR RTSI/PXI Triggers Connector 0 (MIO) PCI/PXI/CompactPCI Bus Figure 2-1. NI7830R Block Diagram NI 7830R Overview NI 7831R/7833R Overview Analog Input User- Configurable FPGA on RIO Devices Connector 0 (MIO) Input Modes Input Range Connecting Analog Input Signals Page Types of Signal Sources Floating Signal Sources Ground-Referenced Signal Sources Input Modes Figure 2-4. Summary of Analog Input Connections Differential Connection Considerations (DIFF Input Mode) Differential Connections for Ground-Referenced Signal Sources Differential Connections for Nonreferenced or Floating Signal Sources Page Single-Ended Connection Considerations Single-Ended Connections for Floating Signal Sources (RSE Input Mode) Single-Ended Connections for Grounded Signal Sources (NRSE Input Mode) Common-Mode Signal Rejection Considerations Analog Output Connecting Analog Output Signals Digital I/O Connecting Digital I/O Signals Page Page RTSI Trigger Bus PXI Local Bus (for NI PXI-783xR only) Switch Settings Page Page Power Connections Field Wiring Considerations Calibration Loading Calibration Constants Internal Calibration External Calibration A Specifications Analog Input Input Characteristics Accuracy Information DC Transfer Characteristics Dynamic Characteristics Settling Time Analog Output Output Characteristics Accuracy Information DC Transfer Characteristics Voltage Output Dynamic Characteristics Digital I/O Reconfigurable FPGA Calibration Bus Interface Power Requirement Physical Maximum Working Voltage Environmental Operating Environment Storage Environment Shock and Vibration (for NI PXI-783xR Only) Safety Electromagnetic Compatibility CE Compliance B Connecting I/O Signals Appendix B Connecting I/O Signals NI 783xR User Manual B-2 ni.com Figure B-2. NI783xR I/O Connector Pin Assignments NI7 83xR DIO NI 7830R MIO NI 7831R/7833R MIO Caution Connections that exceed any of the maximum ratings of input or output signals Table B-1. I/O Connector Signal Descriptions Connecting to CompactRIO Extension I/O Chassis Table B-2. NI783xR I/O Signal Summary Connecting to 5B and SSR Signal Conditioning Figure B-3. Connector Pinouts when Using NSC68-262650 Cable AO 07 Connector AI 07 Connector DIO 015 Connector Figure B-4. Connector Pinouts when Using the NSC68-5050 Cable DIO 023 Connector DIO 2439 Connector C Using the SCB-68 Shielded Connector Block D Technical Support and Professional Services Page Glossary Numbers/Symbols A B C D Page I L M N O P R S T V W