Technical data

2Performance Tests
32 N1911A/1912A P-Series Power Meters Service Guide
Linearity (Average Path)
Description
Linearity over the full input voltage range of the measurement path is
warranted to provide assurance of instrument accuracy. This test measures
linearity by using a calibration DAC and a calibration ADC (built into the
DUT) to stimulate and compare performance of the average path against
the measurement ADC, returning the worst case percentage error.
Equipment
• No test equipment required
Test Method
1 Execute the internal linearity measurement procedure for channel A.
2 Read back the result of the measurement from the DUT.
3 If the DUT model number is N1912A, then repeat this procedure for
channel B.
4 The test will take a few minutes to complete.
5 The measurement result should be less than 0.5 and greater than –0.5.
The optimum measurement result for this test is 0.
NOTE
• This test can be performed manually via the commands:
SERV:BIST:CW[1|2]:LIN
SERV:BIST:CW[1|2]:LIN:PERR?
(Refer to the programming guide for further details on the use of these commands)
• No adjustment is available for this test if it fails (see Chapter 5, “Troubleshooting
Guide”).