National Instruments USB-6008/6009 Computer Drive User Manual


 
USB-6008/6009 User Guide and Specifications 10 ni.com
Analog Input
You can connect analog input signals to the USB-6008/6009 through the
I/O connector. Refer to Table 5 for more information about connecting
analog input signals.
Analog Input Circuitry
Figure 5 illustrates the analog input circuitry of the USB-6008/6009.
Figure 5. Analog Input Circuitry
MUX
The USB 6008/6009 has one analog-to-digital converter (ADC). The
multiplexer (MUX) routes one AI channel at a time to the PGA.
PGA
The progammable-gain amplifier provides input gains of 1, 2, 4, 5, 8, 10,
16, or 20 when configured for differential measurements and gain of
1 when configured for single-ended measurements. The PGA gain is
automatically calculated based on the voltage range selected in the
measurement application.
A/D Converter
The analog-to-digital converter (ADC) digitizes the AI signal by
converting the analog voltage into a digital code.
AI
+2.5 V
REF
39.2 k
127 k
30.9 k
PGA
Input Range
Selection
AI FIFO
ADC
MUX