Galvanically isolated functional test for components

摘要

A method and a circuit functionally test a semiconductor component. The functional test is performed with galvanic isolation by using a transformer. The test itself is based on determining the frequency-dependent impedance of a series circuit of capacitors and inductors using the semiconductor component itself. The impedance is strongly influenced by the conduction state of the semiconductor component, in other words, by the instantaneous conductivity or blocking capability of the semiconductor component.

主权项

1. A method for testing a switch, comprising:
connecting the switch to an electrical test circuit which has a transformer; producing an AC voltage in the test circuit; determining an impedance of the test circuit and the switch for the AC voltage; selecting a conductivity state of the switch to be tested, the conductivity state being selected from first and second conductivity states, the first conductivity state representing the switch being switched-on, and the second conductivity state representing the switch being switched-off; and selecting a frequency for the AC voltage, which is matched to the conductivity state to be tested, wherein the frequency is selected such that when the switch is in at least one of the first and second conductivity states, the impedance determined should be virtually zero.