MOTOR CONTROL CIRCUIT WITH MALFUNCTION MONITORING

摘要

The invention relates to a control circuit used for the control of safety-critical functions of a consumer with an inductive load portion, and to a malfunction monitoring method. The consumer is intended for connection to a direct voltage source. The invention proceeds from a control circuit having a power drive subassembly, a freewheel drive subassembly and a reverse battery protection subassembly. In order to increase the probability of malfunction recognition, the control circuit is expanded to include a malfunction monitoring method. For that purpose, the semiconductor switches of the subassemblies, each formed by a MOSFET, are individually driven. The various switching states are checked by a diagnosis device which processes voltage values read across the outputs of the control circuit. In this manner, both malfunction-free operation and possible causes of control circuit malfunction can be diagnosed.