National Instruments 622 Series, User Manual

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Chapter 3 Connector and LED Information
Table 3-1. I/O Connector Signals
Signal Name Reference Direction Description
AI GND — —
Analog Input Ground
—These terminals are the
reference point for single-ended AI measurements
in RSE mode and the bias current return point for
DIFF measurements. All three ground
references—AI GND, AO GND, and
D GND—are connected on the device. Refer to
the
Connecting Analog Input Signals
section of
Chapter 4,
Analog Input
.
AI <0..79> Varies Input
Analog Input Channels
—For single-ended
measurements, each signal is an analog input
voltage channel. In RSE mode, AI GND is the
reference for these signals. In NRSE mode, the
reference for each AI <0..15> signal is
AI SENSE; the reference for each AI <16..63>
and AI <64..79> signal is AI SENSE 2
* .
For differential measurements, AI 0 and AI 8 are
the positive and negative inputs of differential
analog input channel 0. Similarly, the following
signal pairs also form differential input channels:
<AI 1, AI 9>, <AI 2, AI 10>, <AI 3, AI 11>, and
so on.
Refer to the
Connecting Analog Input Signals
section of Chapter 4,
Analog Input
.
AI SENSE,
AI SENSE 2 — Input
Analog Input Sense
—In NRSE mode, the
reference for each AI <0..15> signal is
AI SENSE; the reference for each AI <16..63>
and AI <64..79> signal is AI SENSE 2
* . Refer to
the
Connecting Analog Input Signals
section of
Chapter 4,
Analog Input
.
AO <0..3> AO GND Output
Analog Output Channels
—These terminals
supply the voltage output. Refer to the
Connecting
Analog Output Signals
section of Chapter 5,
Analog Output
.
AO GND — —
Analog Output Ground
—AO GND is the
reference for AO <0..3>. All three ground
references—AI GND, AO GND, and
D GND—are connected on the device. Refer to
the
Connecting Analog Output Signals
section of
Chapter 5,
Analog Output
.