CALIBRATION
M9B-HFS INTERFACE
4-2
Release 1.0 (97/10)
4.2.2
Voltage Program Calibration Procedure
1. Set up for calibration as in Section
4.2.1 Voltage Calibration Setup.
2. Activate calibration mode by sending command CMODE ON.
3. Send commands VLO; ILO to the power supply. Measure and record the output voltage shown on the
external voltmeter.
4. Send commands VHI; IHI to the supply. Measure and record the output voltage shown on the external
voltmeter.
5. Send the command VDATA <vlo>,<vhi> to the power supply. <vlo> and <vhi> are the voltage values
taken from the voltmeter when the VLO and VHI commands were sent. When the power supply is
calibrated, the <vlo> and <vhi> voltage values are stored as constants.
6. Program the supply at various levels using the VSET command to confirm that the calibration was
successful and that linearity is observed. See the voltage program accuracy specification in
Appendix A.
7. Turn off calibration mode by sending the command CMODE
OFF to the supply.
4.2.3
Voltage Readback Calibration Procedure
1. Set up for calibration as in Section
4.2.1 Voltage Calibration Setup.
2. Send the software command CMODE ON to activate calibration mode.
3. Send command VRLO; IRLO to the power supply. Wait for supply to settle. Measure and record the
output shown on the external voltmeter. Send VRLO again.
4. Send command VRHI; IRHI to the supply. Wait for the supply to settle. Measure and record the output
voltage shown on the external voltmeter. Send VRHI again.
5. Send the command VRDAT <vlo>,<vhi> to the power supply. <vlo> and <vhi> are the voltage values
obtained from the voltmeter by sending the VRLO and VRHI commands. The processor calculates the
offset value required to calibrate the power supply. When the power supply is calibrated, the low to
high voltage readback calibration values (offsets) are stored as constants.
6. Use commands VSET and VOUT? to confirm that the calibration was successful and that linearity is
observed. Refer to the voltage readback accuracy specification in Appendix A.
7. Turn off calibration mode by sending the CMODE
OFF command to the supply.