| 摘要 |
<P>PROBLEM TO BE SOLVED: To solve the problem of a chain destruction caused by a flow of penetration current between a high-side switching element and a low-side switching element, which occurs by a withstand-voltage breakage of a high-side drive circuit resulting from a short circuit between a terminal to which an input voltage is applied and a BS terminal to which a bootstrap voltage is applied. <P>SOLUTION: A DC-DC converter comprises: differential voltage detection means for detecting the voltage at the both ends of a bootstrap capacitor; and control means for switching off a low-side MOSFET when a voltage detected by the differential voltage detection means is above a prescribed value. When a short circuit occurs between a terminal to which an input voltage is applied and a BS terminal to which a bootstrap voltage is applied, a flow of penetration current between a high-side switching element and a low-side switching element is stopped by switching off a low-side switching element, thus a chain destruction can be prevented. <P>COPYRIGHT: (C)2012,JPO&INPIT |
