Semiconductor device

Abstract

A first clamp circuit 4 clamps a voltage between a gate of a switching element Q1 and a first terminal to a first clamp voltage or lower. A control circuit 2 that controls the switching element Q1 has: a drive unit 5 that drives the switching element Q1; an abnormality detection unit 9 that stops the drive unit 5 when an operation abnormality is detected; and a second clamp circuit 10. At the timeof stopping the drive unit 5 by means of the abnormality detection unit 9, the second clamp circuit 10 clamps the voltage between the gate and the first terminal to a second clamp voltage or lower, said second clamp voltage being lower than the first clamp voltage.

Description

technical field [0001] The present invention relates to semiconductor devices. Background technique [0002] Power semiconductor devices that drive L loads such as transformers are used in ignition systems for internal combustion engines such as automobile engines. Such a semiconductor device has a function of shutting off the main current by detecting abnormal heat generation or a function of shutting off the main current when an ON signal is continuously applied for a certain period of time or more to avoid burnout and damage. This shutdown operation is performed for the self-protection of the semiconductor device, so there is a high possibility that its timing is different from the ignition signal of the engine control computer. Depending on the timing of the shutoff operation, problems such as flashback and knocking of the engine may occur, which may cause damage to the engine mechanism. In order to prevent these situations, it is necessary to implement a slow main cur...

AI Technical Summary

Problems solved by technology

Depending on the timing of the breaking operation, there is a risk of engine flashback, knocking, etc., causing damage to the engine mechanism

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