Chapter 3
Adjustment
3-8
ni.com
Determining the Interactions of Gains and Offsets in the Main
DAC and Gain Calibration DAC (Constants A3 and A4)
To calculate constants, sweep the full range of the 12-bit main DAC (–2048 to
2047) by calling
ni54xx_GenerateWaveform
with the amplitude
parameter set to correspond to the DC value of each DAC setting. Table 3-2
shows the corresponding input values and expected output voltage of the
main DAC.
1.
Set the offset calibration DAC to 0 by calling the function
ni54xx_SetOffsetDAC
. Set the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
DACValue
—
0
2.
Set the gain calibration DAC to 0 by calling the function
ni54xx_SetGainDAC
. Set the following parameters:
•
sessionHandle
—The handle of the calibration session for the
device
•
DACValue
—
0
Table 3-2.
Input Values and Expected Output Values
DAC Value
Output (V)
–2048
–10
–1536
–7.5
–1024
–5
–512
–2.5
0
0
512
2.5
1024
5
1536
7.5
2047
10