Keithley 2520, Service Manual, Page: 42 / 137

2-12 Calibration Model 2520 Pulsed Laser Diode Test System Service Manual
6. Connect the calibrator to the Model 2520 testhead VOLTAGE SENSE jacks, as
shown in Figure 2-2 . (Connect calibrator HI to VOLTAGE SENSE LO; connect
calibrator LO to VOLTAGE SENSE HI.)
7. Turn on the calibrator output, set the calibrator voltage to -10.000V, then press
ENTER. The unit will prompt you as follows:
VL-CAL
Switch HI and LO connections
8. Switch the HI and LO calibrator connections, then press ENTER.
9. Press EXIT to return to normal display.
10. Press the LASER V
L
key to make sure the laser volts mode is selected.
11. Press the RANGE key to select the 5V range.
12. Repeat steps 2 through 9 for the 5V range. Be sure to set the calibrator output to
-5.000V as shown in Table 2-4 .
Figure 2-2
Voltage measurement calibration connections
CURRENT
OUTPUT
VOLTAGE
SENSE
CAT I
DETECTOR 1 DETECTOR 2
BIAS
CURRENT
INPUT
ISOLATION FROM EARTH: 10V MAX.
HI
HI
LO
LO
!
!
Model 2520 Testhead
BNC Cables
Output
HI
Calibrator (Output DC Voltage)
VOLTAGE
SENSE HI
VOLTAGE
SENSE LO
Output LO
Step 3: Current source calibration
Follow the steps below to calibrate the current source. Table 2-5 summarizes calibration
resistors.
1. From normal display, press the Model 2520 LASER V
L
key, then set the range to
10V range using the RANGE key.
2. Press the LASER I
L
key, press the EDIT key, then set the source to the 500mA
range using the RANGE key.
3. Press the MENU key, select CAL, then press ENTER.
4. Select EXECUTE, then press ENTER to enter the calibration menu.