National Instruments NI 6238 - Manual (Page 27)

© National Instruments Corporation 4-1 NI 6238/6239 User Manual
4
Analog Input
Figure 4-1 shows the analog input circuitry of NI 6238 and NI 6239
devices.
Figure 4-1. NI 6238/6239 Analog Input Circuitry
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 is outlined in the
Connecting Analog Current Input Signals section. Also refer to
Appendix A, 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.
Instrumentation Amplifier (NI-PGIA)
The NI programmable gain instrumentation amplifier (PGIA) is a
measurement and instrument class amplifier that minimizes settling times
I/O Connector
AI <0..7>+
AI GND
NI-PGIA
Input Range
Selection
ADC AI Data
Isolation
Barrier
Digital
Isolators
AI FIFO
AI <0..7>–
Mux
AI Terminal
Configuration
Selection