Tektronix TPR1000, Руководство пользователя

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Performance veri fi cation
Table 11: Example calculation of measured gain
Vout (linear fi t) slope Vin slope Measured gain
0.257 0.320 0.803125
Check the DC input dynamic range
Use the following test to check the DC input dynamic range of the probe.
1. Connect the test equipment as shown in the DC setup diagram. (See Figure 6.)
2. Before attaching the probe to the TekVPI Calibration Veri fi cation adapter, measure the resistance of the feed-thru
termination with the DMM.
3. Record its value. If it is out of speci fi cation, replace it before continuing the test.
4. Attach the probe to the TekVPI Calibration Veri fi cation adapter.
5. Ensure the probe offset is set to 0 V.
6. Set the DMM to DC Volts autoranging.
NOTE. When using the DMM function in a Keithley SMU, turn on FILTER to reduce transient output values.
7. Set the DC source current limit to 3 mA.
8. Set the source measure unit (SMU) to +1 V and record the output voltage on the DMM.
9. Set the source measure unit (SMU) to –1 V and record the output voltage on the DMM.
10. Using the readings taken in steps 8 and 9, apply the following equation to calculate the gain of the probe:
Gain
probe
= V
source
÷ V
measured
11. Verify that the gain is at least 90% of the nominal gain range for each input by dividing it by the nominal expected gain
and multiplying by 100:
100 x Gain
measured
÷ Gain
nominal
12. If the value is >90%, then that limit of the dynamic range is veri fi ed.
13. Record results in test record.
14. Switch the probe to DC Reject mode.
15. While measuring the output, apply +1 V and –1 V to the input of the probe.
16. Ensure that output does not shift by more than 0.01 V during the test. Result is reported as Pass or Fail.
17. Return the probe to DC Coupling mode.
18. Record the result in the test record. (See page 34.)
TPR1000 and TPR4000 User Manual 31