Patent ID: 8232830

Claim:
A rectifier, external terminals of which are two terminals that are an anode terminal and a cathode terminal, the rectifier comprising: a semiconductor switching device connected between the two terminals, which is drive-controlled via a gate electrode thereof; a parallel diode, connected in parallel to the semiconductor switching device, for performing a rectifying operation when the rectifier starts operating; and a drive signal generator configured to output a drive signal to the gate electrode of the semiconductor switching device, the drive signal generator using, as a power source, a forward voltage that occurs between the two terminals when a voltage is applied across the anode and cathode terminals so that the two terminals are conductive with each other, whereby the semiconductor switching device is driven in an ON state for a duration of the forward voltage, and the drive signal generator includes: a boosting circuit configured to boost the forward voltage, which occurs between the two terminals when the two terminals are conductive with each other, to a predetermined voltage, and the boosting circuit is formed with a preceding-stage boosting section and a subsequent-stage boosting section, and a drive control circuit configured to output the drive signal to the gate electrode of the semiconductor switching device, the drive control circuit using an output of the boosting circuit as a power source, wherein the subsequent-stage boosting section is activated by a voltage boosted by the preceding-stage boosting section, and boosts the forward voltage, which occurs between the two terminals, to the predetermined voltage and outputs the predetermined voltage, and uses the outputted predetermined voltage as a power source voltage for causing the subsequent-stage boosting section to operate.