Chapter 8116Calibrating the Analog Output SubsystemThis section describes how to use the calibration utility to calibrate the analog outputsubsystem of a DT9837, DT9837A, or DT9837C module.To calibrate the analog output circuitry, you need to connect an external precision voltmeter toanalog output channel 0 of the DT9837, DT9837A, or DT9837C module.Do the following to calibrate the analog output circuitry:1. Select the D/A Calibration tab of the calibration utility.2. Connect an external precision voltmeter to Analog Output 0 (DAC Ch0) of the DT9837Series module.3. In the DAC Output Voltage box, select –9.375 V for the DT9837 and DT9837A, or –2.75 Vfor the DT9837C.4. Adjust the offset by entering values between 0 and 255 in the DAC 0 Offset edit box or byclicking the up/down buttons until the voltmeter reads –9.375 V for the DT9837 andDT9837A, or –2.75 V for the DT9837C.5. In the DAC Output Voltage box, select 9.375 V for the DT9837 and DT9837A, or 2.75 V forthe DT9837C.6. Adjust the gain by entering values between 0 and 255 in the DAC 0 Gain edit box or byclicking the up/down buttons until the voltmeter reads 9.375 V for the DT9837 andDT9837A, or 2.75 V for the DT9837C.Note: At any time, you can click Restore Factory Settings to reset the D/A calibrationvalues to their original factory settings. This process will undo any D/A calibration settings.Once you have finished this procedure, the analog output circuitry is calibrated. To close thecalibration utility, click the close box in the upper right corner of the window.
