National Instruments NI 5922, Calibration Procedure

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© National Instruments Corporation 25 NI 5922 Calibration Procedure
6. Connect the scope calibrator to the external trigger channel of the
digitizer. Configure the calibrator to output an exact 1 MHz sine wave
with 0.3 V peak-to-peak amplitude and 1 M
Ω
load impedance.
7. Wait 1,500 ms for the calibrator impedance matching and frequency to
settle.
8. Call
niScope_InitiateAcquisition
(niScope Initiate
Acquisition VI) with the following parameter:
• vi : The instrument handle you obtained from
niScope_init
9. Call
niScope_Fetch
(niScope Multi Fetch VI) with the following
parameters:
• channelList :
"0"
• timeout :
2.0
• numSamples :
–1
If the digitizer does not time out, the digitizer has passed this portion
of the verification. If the digitizer has a timeout error, call
niScope_Abort
(niScope Abort VI) to end the acquisition.
10. Repeat steps 1 through 9, changing the value of the the slope
parameter from
"NISCOPE_VAL_POSITIVE"
to
"NISCOPE_VAL_NEGATIVE"
.
Note The NI 5922 uses the digitized data from the input channel ADC when performing
an analog trigger on CH 0 or CH 1. Verifying the trigger sensitivity for the input channels
is not necessary.
Adjusting the NI 5922
If the NI 5922 successfully passed each of the verification procedures
within the calibration test limits, then an adjustment is recommended but
not required to guarantee its published specifications for the next two years.
If the digitizer was not within the calibration test limits for each of the
verification procedures, you can perform the adjustment procedure to
improve the accuracy of the digitizer. Refer to the
External Calibration
Options section to determine which procedures to perform.
An adjustment is required only once every two years. Following the
adjustment procedure automatically updates the calibration date and
temperature in the EEPROM of the digitizer.
Note If the digitizer passed the entire verification procedure within the calibration test
limits and you do not want to perform an adjustment, you can update the calibration date
and onboard calibration temperature without making any adjustments by completing
only
steps 4 and 13 in this section.