| 摘要 |
PROBLEM TO BE SOLVED: To perform protection by appropriately controlling a gate voltage in a drive device that performs ON/OFF control of a power switching element and the protection in the case of abnormality.SOLUTION: The drive device includes a protection circuit for controlling a gate current on the basis of a current value of a collector current of the power switching element. The protection circuit includes: a constant current circuit which specifies a constant current for extracting gate charge of the power switching element; a protection switch for controlling an electrical connection between the constant current circuit and a gate of the power switching element; and a collector current detection section for detecting that the current value of the collector current of the power switching element exceeds a predetermined threshold. If the current value of the collector current of the power switching element exceeds a first threshold indicating short-circuiting of a load as the predetermined threshold, after the lapse of a predetermined time the collector current detection section turns off an ON-side circuit, disconnects the power switching element from a main power source and turns on the protection switch. |
