Agilent Technologies 4156b, User Manual

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8-10 Agilent 4155B/4156B User’s Guide Vol.2, Edition 5
If You Have A Problem
When You Make A Measurement
If Measurement Damages the Device under Test
When Using SMU
When performing breakdown measurements by using SMU, DUTs may be
damaged.
When voltage is forced from an SMU, the current is limited by the compliance
setting, which prevents the DUT from being damaged by a large current. But when
the current rapidly increases, the current limiter in the SMU cannot follow the rapid
current increase, so a large amount of current may flow through the DUT for a
moment, which may damage the DUT.
To solve this problem:
• Insert a protecting resistor as close as possible to DUT. You can also use a
resistor of Agilent 16441A R-Box.
When Using VMU
When using VMU, the measurement terminal voltage increased by charge of buffer
amplifier current in VMU, may damage DUT.
When the measurement terminal of VMU is open and when a coaxial cable is
connected to VMU, buffer amplifier current charges increase the VMU terminal
voltage. After a long time charge, the increased terminal voltage is discharged by
connecting DUT, which may damage the DUT.
To solve this problem:
There are three ways to prevent this problem as follows: