Keithley 2651A Reference Manual page 724

Appendix B: Calibration
2. Select the correct sense mode based on the calibration step for the voltage source and
measure function from the
smua.sense = smua.SENSE_LOCAL
3. Select positive polarity, and then set the source output to the positive zero value. For
example:
smua.cal.polarity = smua.CAL_POSITIVE
smua.source.levelv = 1e-30
4. Turn on the output:
smua.source.output = smua.OUTPUT_ON
5. Allow the readings to settle, then get both the multimeter and Model 2651A voltage readings
at the positive zero value (the Model 2651A measurement is not necessary if this calibration
step is being done on the CALA sense mode). The two measurements should be made as
close as possible in time. Use this command for the Model 2651A:
Z_rdg = smua.measure.v()
6. Turn off the output:
smua.source.output = smua.OUTPUT_OFF
7. Set the source output to the positive full-scale value for the present range, for example:
smua.source.levelv = 0.9
8. Turn on the output:
smua.source.output = smua.OUTPUT_ON
9. Allow the readings to settle, then get both the multimeter and Model 2651A voltage readings
at the positive full-scale output value (the Model 2651A measurement is not necessary if this
calibration step is being done on the CALA sense mode). The two measurements should be
made as close as possible in time. Use this command for the Model 2651A:
FS_rdg = smua.measure.v()
10. Turn off the output:
smua.source.output = smua.OUTPUT_OFF
11. Send the source calibration command using the range, +zero and +FS multimeter readings,
and +zero and +FS source values for the parameters:
smua.source.calibratev(range, src_Z, DMM_Z_rdg, src_FS, DMM_FS_rdg)
Where:
range
src_Z
DMM_Z_rdg
src_FS
DMM_FS_rdg
Typical values for the Model 2651A 1 V range:
smua.source.calibratev(1, 1e-30, 1e-5, 0.9, 0.903)
12. If this step is not on the CALA sense mode, send the measure calibration command using the
multimeter and Model 2651A readings, and the range setting for the parameters. For
example:
smua.measure.calibratev(range, Z_rdg, DMM_Z_rdg, FS_rdg, DMM_FS_rdg)
B-24
Model 2651A High Power System SourceMeter® Instrument Reference Manual
Model 2651A step sequence
= The present calibration range
= The +zero Model 2651A source output value
= The +zero DMM measurement
= The +FS Model 2651A source output value
= The +FS DMM measurement
(on page B-19), for example:
2651A-901-01 Rev. A / March 2011