| 摘要 |
PURPOSE: To simplify the configuration of a protection circuit, reduce the space for incorporating a device for miniaturization, and at the same time make positive protection operation by providing a protection detection circuit for judging that a level which is equal to or less than a prescribed value is normal and providing a breaking circuit for breaking an input signal with the output signal of the protection detection circuit. CONSTITUTION: Connection is made to the input of an exclusive OR circuit element EX-OR1 via a resistor R14 from a gate signal (a terminal D) of a gate drive circuit 18. A series of resistor R11, R12, and R13 are connected to a Zener diode ZD1. A diode D31 is connected from the output of the exclusive OR circuit element EX-OR1 and an anode side is set to a terminal F. Similarly, connection is made to the output terminal F from a diode D21, resistors R22 and R23, and an exclusive OR circuit element EX-OR2 for the switching element Q6. Since a simple circuit prevents the switching element of a power conversion circuit from being damaged due to load short-circuiting and arm short-circuiting, thus saving space. |
