Pmu Connection Compensation; Short Compensation - Keithley 4200A-SCS User Manual

Section 2: Connections

PMU connection compensation

You can correct errors caused by connections and cable length between the 4225-PMU and the
device under test (DUT) by using connection compensation. When connection compensation is
enabled, the default or measured compensation values are factored into each DUT measurement.
Connection compensation includes short and offset current compensation options.
You have the option to use either default connection compensation values (PMU or RPM) or custom
connection compensation values. The default values can be used for typical connection setups that
use the supplied cables. The custom connection compensated values are generated when
connection compensation is done from the Clarius software. The custom values provide optimum
compensation. Custom connection compensation data is generated for offset current and short
conditions. The custom connection compensation values can be enabled or disabled from a test in
Clarius.
If connection compensation is disabled, the compensation values will not be applied to the
measurements.
For optimum performance, you should do connection compensation any time the connection setup is
changed or disturbed. Changes in temperature or humidity do not affect connection compensation.

Short compensation

For UTMs, the default connection compensation values for short can only be enabled using the
pulse_conncomp function, which is described in Model 4200A-SCS LPT Library Programming.
You can perform short compensation to remove measurement errors due to stray resistance in your
test configuration. When you run short connection compensation, the following status messages are
generated:
•
Starting PMU Cable Compensation...
•
R = % Ohms
•
PMU Cable Compensation complete.
% = value (V and I measured, Ohms calculated).
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Model 4200A-SCS Pulse Card (PGU and PMU) User's Manual
4200A-PMU-900-01 Rev. A December 2020