Device for testing e.g. insulated gate bipolar transistor, in power circuit, has control circuit changing threshold value of comparing circuit and/or detection time point for detecting characteristic value

摘要

The device (100) has a voltage or power supply circuit (50) supplying voltage and/or current to a device (200) to be tested. A comparing circuit (40) detects characteristic value for finding the state of the device to be tested, and compares the characteristic value with a predetermined threshold value. A shut-off unit (60) switches-off the voltage or current supplied from the supply circuit to the device to be tested depending on the comparison result. A control circuit (10) changes the threshold value of the comparing circuit and a detection time point to detect the characteristic value.