| 摘要 |
PURPOSE: To protect against the abnormal state of equipment by outputting each different failure signal corresponding to the details of abnormality of, for example, the abnormal eddy current of a semiconductor switching element, a control power supply voltage abnormal reduction, and abnormal overheat of a semiconductor compound element. CONSTITUTION: A first abnormal state detection part 51 consists of a positive side eddy current protection circuit 31a and a positive side control power supply voltage reduction protection circuit 32a and a second abnormal state detection part 52 consists of a negative side current protection circuit 31b, a negative side control power supply voltage reduction protection circuit 32b, and an overheat protection circuit 34. A first failure signal generation part 53 receives the output signals of the positive side eddy current protection circuit 31a and the positive side control power supply voltage reduction protection circuit 32a and outputs an output signal corresponding to the input signal. Also, a second abnormal state detection part 54 receives the output signals of the negative side overcurrent protection circuit 31b, the negative side control power supply voltage reduction protection circuit 32b, and the overcurrent protection circuit 34 and outputs an output signal corresponding to the input signal. |
