| CPC H03K 17/0828 (2013.01) [H03K 17/16 (2013.01); H03K 19/00346 (2013.01)] | 8 Claims |

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1. A switching element drive circuit for driving an N-channel switching element having a gate electrode with an insulated gate structure, comprising:
a gate drive circuit that outputs a gate drive signal based on an element control signal received from outside;
a gate resistor interposed between an output of the gate drive circuit and a gate electrode of the switching element, having one end thereof connected to a first node on an output side of the gate drive circuit, and having an other end thereof connected to a second node on a gate electrode side of the switching element;
a PNP bipolar transistor having an emitter connected to the second node and a collector connected to a reference potential;
a diode having an anode connected to the first node and a cathode connected to a base of the PNP bipolar transistor at a third node;
a base connection resistor having one end thereof connected to the third node; and
a base drive circuit that outputs a base drive signal based on the element control signal, wherein
the base drive signal is given to an other end of the base connection resistor,
a voltage obtained from the second node becomes a gate voltage of the switching element,
the gate drive circuit
sets a gate drive voltage of the gate drive signal to a power supply voltage during an On-operation period in which the element control signal indicates an On state of the switching element, and
sets the gate drive voltage of the gate drive signal to the reference potential during an Off-operation period in which the element control signal indicates an off state of the switching element, and
the base drive circuit
sets a base drive voltage of the base drive signal to the reference potential during the On-operation period, and
turns Off the PNP bipolar transistor by the base drive signal during at least a partial period in the Off-operation period.
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