Keysight Technologies B1500A Self-Paced Training Manual page 113

Module 3
Low Current Measurement
You can trade off speed vs accuracy by varying the LIMITED range setting or the integration time
setting.
The 100 nA range will speed up the test but you will lose low-end resolution. Try setting LIMITED
to 10 pA range or 100 pA range. Accuracy increases but speed slows considerably.
For the integration time, small factor value will speed up but accuracy decreases.
Also measurement speed will be changed by the Mode setting. Set the mode which provides
applicable measurement results.
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