Analog Input; Analog Input Circuitry - National Instruments NI USB-621x User Manual

Analog Input

AI <0.. n >
AI SENSE
AI GND

Analog Input Circuitry

© National Instruments Corporation
Figure 4-1 shows the analog input circuitry of NI 621x devices.
MUX
DIFF, RSE,
NI-PGIA
or NRSE
Input Range
Selection
AI Terminal
Configuration
Selection
Figure 4-1. M Series Analog Input Circuitry
I/O Connector
You can connect analog input signals to the M Series device through the I/O
connector. The proper way to connect analog input signals depends on the
analog input ground-reference settings, described in the
Ground-Reference Settings
Device-Specific Information, for device I/O connector pinouts.
MUX
Each M Series device has one analog-to-digital converter (ADC). The
multiplexers (MUX) route one AI channel at a time to the ADC through the
NI-PGIA.
and USB-6218
ADC AI FIFO
section. Also refer to Appendix A,
4-1
4
Isolation
Barrier
(USB-6215
devices only)
Digital
AI Data
Isolators
Analog Input
NI USB-621x User Manual