10
|
ni.com
|
NI USB-6000 User Guide
Analog Input
The NI USB-6000 has eight ±10 V fixed-range analog input channels for single-ended analog
input measurements.
Figure 5 shows the analog input circuitry of the NI USB-6000.
Figure 5.
NI USB-6000 Analog Input Circuitry
The main blocks featured in the analog input circuitry are as follows:
•
MUX
—The multiplexer (MUX) routes one AI channel at a time to the amplifier (AMP).
•
AMP
—The amplifier (AMP) buffers analog input signal, before the signal is sampled by
the analog-to-digital converter (ADC).
•
ADC
—The analog-to-digital converter (ADC) digitizes the AI signal by converting the
analog voltage into digital code.
•
AI FIFO
—The NI USB-6000 can perform both single and multiple analog-to-digital
conversions of a fixed or infinite number of samples. A first-in-first-out (FIFO) buffer
holds data during AI acquisitions to ensure that no data is lost.
PFI 1
D GND
Input
PFI 1
—A digital trigger input. Refer to the
Using PFI 1 to Trigger an Analog Input
Acquisition
section for more information.
AI <0..7>
AI GND
Input
Analog Input Channels 0 to 7
—Analog
input voltage channels. Refer to the
Analog
Input
section for more information.
Table 4.
Signal Descriptions (Continued)
Signal
Name
Reference
Direction
Description
AI 7
AMP
AI FIFO
ADC
MUX
AI 0
1 M
Ω
1 M
Ω
