| 摘要 |
<p>PROBLEM TO BE SOLVED: To achieve stable protection from overcurrent by suppressing fluctuations in currents running through a switching element after overcurrent detection.SOLUTION: A peak value reach time detection circuit 5a detects a peak value reach time until a current running through a switching element reaches a peak value. A differential voltage detection circuit 5b includes a 1/2-hour detection circuit 5b-1 that detects 1/2 hours relative to on time in the previous period of the switching element and detects a differential voltage between a reference voltage in detecting an overcurrent relative to a load and a signal detecting a current running through the switching element at 1/2 hours. A delay time adjustment circuit 5c performs adjustment control of delay time generated until the switching element is turned off after detection of an overcurrent, on the basis of at least either one of the peak value reach time and the differential voltage.</p> |
