© National Instruments Corporation 27 NI 9144 User Guide and Specifications
The calibration data is stored in a U32 array, though each offset field should
be interpreted as a signed value.
Use the calibration coefficients with the following equation to generate
corrected data:
Table 12. NI 9203 Calibration Coefficients
Coefficient Representation Units
LSB Weight Unsigned pA/LSB
Offset Signed pA
Table 13. NI 9203 Calibration Equation Information
Term Units Definition
Icorrected pA Calibrated current
Iraw bits The raw code from the
NI 9203
Iexpected0mA bits Expected code at 0 mA.
0 bits for 0–20 mA range.
32768 bits for ±20 mA
range
LSBweight pA/bit Number of pA in one bit
Ioffset pA Offset at 0 mA
Icorrected Iraw
() Iraw Iexpected 0mA
–∗LSBweight Ioffset
–=
pA bits pA/bit pA
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