| 摘要 |
PROBLEM TO BE SOLVED: To provide a failure detector which can hold a failure-detected state for a sufficient period of time. SOLUTION: A failure detector for a switching element comprises a first detection circuit 8 which detects a first failure of a switching element 4 based on a first reference value Vref1 and outputs a first failure detection signal; a second detection circuit 9 which detects a second failure of the switching element based on a second reference value Vref2 and outputs a second failure detection signal; an OR circuit 10 which outputs a failure detection signal when at least either of the first failure detection signal and the second failure detection signal is output; and an AND circuit 2 which outputs an OFF signal to the switching element when the failure detection signal is output from the OR circuit, regardless of a gate signal 1 to the switching element. The failure detector is equipped with a switching circuit 95 for switching the second reference value Vref2 to a third reference value Vref3 at which the second failure detection signal is output when the first failure detection signal is output. COPYRIGHT: (C)2010,JPO&INPIT
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