Patent ID: 9667061
Date: 2017-05-30
CPC Classifications: G08B,H02H,H02M,H03K

Claim:
1. A semiconductor element drive device, comprising: a drive circuit configured to drive a semiconductor element; a plurality of protection circuits configured to detect information related to protecting the semiconductor element, to generate protection signals, and to stop the drive of the semiconductor element by the drive circuit in accordance with the protection signals; an alarm generation circuit configured to generate alarm signals with pulse widths corresponding to protection factors in accordance with the protection signals output from the protection circuits; an output circuit configured to output the alarm signals at a level; a protection cancellation circuit configured to generate a protection cancellation signal over a fixed period when outputs of the plurality of protection signals from the plurality of protection circuits stop and outputs of the alarm signals from the alarm generation circuit stop; and an output control circuit configured to change a signal output level of the output circuit in accordance with the protection cancellation signal.