Patent ID: 6292342
Filing Date: 2001-09-18
Classification: G01R,H02H

Abstract:
A voltage protection circuit to be used in a semiconductor test system by functioning both as an excessive voltage clamp circuit and an abnormal voltage detection circuit, comprising:a switch for selecting a reference voltage out of a predetermined clamp voltage and a predetermined abnormal threshold voltage;a clamp diode connected to an output of a device under test (DUT) to open or close the output of the DUT;a buffer amplifier for providing the selected reference voltage to the clamp diode;a resister series connected between an output of the buffer amplifier and the clamp diode for detecting an abnormal voltage in the output of the DUT; anda comparator for comparing the reference voltage and an output voltage of the DUT through the clamp diode and generating a detection signal when the output of the DUT exceeds the reference voltage.