Keithley 2651A Reference Manual page 728

Appendix B: Calibration
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.calibratei(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 100 mA range:
smua.source.calibratei(100e-3, 1e-30, 1e-5, 90e-3, 88e-3)
12. If this step is not on the CALA sense mode or 100 A range, send the measure calibration
command using the multimeter and Model 2651A readings, and range setting for the
parameters:
smua.measure.calibratei(range, Z_rdg, DMM_Z_rdg, FS_rdg, DMM_FS_rdg)
Where:
range
Z_rdg
DMM_Z_rdg
FS_rdg
DMM_FS_rdg
Typical 100 mA range values:
smua.measure.calibratei(100e-3, 1e-6, 1e-5, 0.089, 0.088)
13. Select negative polarity, then set the source output to the negative zero value, for example:
smua.cal.polarity = smua.CAL_NEGATIVE
smua.source.leveli = -1e-30
14. Turn on the output:
smua.source.output = smua.OUTPUT_ON
15. Allow the readings to settle, then get both the multimeter and Model 2651A current readings
at the negative zero value (the Model 2651A measurement is not necessary if this calibration
step is being done on the CALA sense mode or 100 A range). The two measurements should
be made as close as possible in time. Use this command for the Model 2651A:
Z_rdg = smua.measure.i()
B-28
Model 2651A High Power System SourceMeter® Instrument Reference Manual
= 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
= The present calibration range
= +zero Model 2651A measurement
= The +zero DMM measurement
= +FS Model 2651A measurement
= The +FS DMM measurement
2651A-901-01 Rev. A / March 2011