Patent ID: 6956427
Filing Date: 2005-10-18
Classification: H03K

Abstract:
1. An electrically insulated type of switching element drive circuit, for controlling on/off operation of a switching element in accordance with an externally supplied control command signal, said switching element drive circuit comprising: a control electrode drive circuit for supplying a drive signal to a control electrode of said switching element, to control said on/off operation based on said control command signal; a power supply circuit for supplying electric power to operate said control electrode drive circuit; a transformer for supplying an AC voltage to said power supply circuit from a secondary side of said transformer, said power supply circuit performing rectification and smoothing of said AC voltage from said secondary side of said transformer to thereby obtain a DC voltage, and supplying said DC voltage to operate said control electrode drive circuit; and an AC voltage output circuit for supplying said AC voltage to a primary side of said transformer; a power transmission system that extends from said AC voltage output circuit to said power supply circuit comprises a resonant circuit, wherein: