NI CF-6004 U
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ide and Specification
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© National In
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7
Analog Inp
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You can connect analog input signals to the NI CF-6004 through the I/O connector. AI GND is
the ground-reference signal for the AI ports. Refer to Table 2 for more information about
connecting analog input signals. Figure 4 illustrates the analog input circuitry of the
NI CF-6004.
Figure 4.
Analog Inp
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t Circ
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itry
The main blocks featured in the NI CF-6004 analog input circuitry are as follows:
•
MUX
—The NI CF-6004 has one analog-to-digital converter (ADC). The multiplexer
(MUX) routes one AI channel at a time to the ADC.
•
AMP
—The amplifier provides an effective input gain of 1.
•
ADC
—The analog-to-digital converter (ADC) digitizes the AI signal by converting the
analog voltage into a digital code.
•
AI FIFO
—The NI CF-6004 can perform both single and multiple A/D 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.
Connecting Single-Ended Voltage Signal
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To connect single-ended voltage signals to the NI CF-6004, connect the positive voltage signal
to the desired AI terminal, and the ground signal to an AI GND terminal.
Figure 5.
Connecting a Single-Ended Voltage Signal
Digital Trigger
You can configure PFI <0..3> as a digital trigger input for analog input tasks. Refer to the
PFI <0..3> as a Digital AI Trigger
section for more information.
AI
AMP
AI FIFO
ADC
MUX
AI
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–
Volt
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NI CF-6004
AI GND
