| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide an overvoltage protection circuit that uses high withstand-voltage elements being easily manufactured and does not need to consider variation in impedance. <P>SOLUTION: An overvoltage protection circuit includes: a drive section 10 that drives a switching element Q1 by a control signal; a differential circuit that is connected between a source and a drain of the switching element and in which a capacitor C2 and a resistor R1 are connected in series; an integration circuit that is connected to both ends of the resistor R1 and in which a resistor R2 and a capacitor C3 are connected in series; and an overvoltage protection section A1, R3, and C4 that determines that a voltage between the drain and source reaches more than or equal to a predetermined voltage when a voltage across the capacitor C3 reaches more than or equal to a reference voltage, and turns on the switching element to clamp the voltage between the drain and the source. <P>COPYRIGHT: (C)2013,JPO&INPIT |
