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Model 4200A-SCS Parameter Analyzer Reference Manual
Section 12: Maintenance
4200A-901-01 Rev. C / February 2017
12-9
Multiple SMU stability considerations
Using two or more SMUs to test an active device, such as a field-effect transistor (FET) or bipolar
junction transistor (BJT), can aggravate system stability. The next figure shows an example of BJT
characterization curves determined under stable conditions.
Figure 493: Effects of oscillation on test data: Without oscillation
The next figure shows an example of what can happen to a BJT characterization curve when the
system oscillates.
Figure 494: Effects of oscillation on test data: With Oscillation