Chapter 2 Hardware Overview ofthe NI 783xR
NI 783xR User Manual 2-14 ni.com
Analog Output
The bipolar output range of the NI 783xR AO channels is fixed at ±10 V.
Some applications require that the AO channels power on to known voltage
levels. To set the power-on levels, you can configure the NI 783xR to load
and run a VI when the system powers on. The VI can set the AO channels
to the desired voltage levels. The VI interprets data written to the DAC in
two’s complement format. Table2-3 shows the ideal AO voltage generated
for a given input code.
Note If your VI does not set the output value for an AO channel, then the AO channel
voltage output will be undefined.
Connecting Analog Output Signals
The AO signals are AO <0..n> and AOGND.
AO <0.. n> are the AO channels. AOGND is the ground reference signal for
the AO channels.
Figure 2-9 shows how to make AO connections to the NI 783xR.
Table 2-3. Ideal Output Voltage and Input Code Mapping
Output Description AO Voltage
Input Code (Hex)
(Two’sComplement)
Full-scale range –1LSB 9.999695 7FFF
Full-scale range –2LSB 9.999390 7FFE
Midscale 0.000000 0000
Negative full-scale range,
+1 LSB
–9.999695 8001
Negative full-scale range –10.000000 8000
Any output voltage —AO Voltage
10.0 V
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