Drive circuit

Abstract

To provide a drive circuit with improved accuracy in determining gate leakage current.SOLUTION: A drive circuit 1 drives a switching element 110 by passing a constant current through a gate terminal 110g of the switching element. The drive circuit includes: a control IC 10; a driving unit that drives the switching element under the control of the control IC; and a comparator 70 connected to the drive unit and the control IC and outputting a monitor signal correlating with a supply state of the constant current to the switching element. The driving unit includes: a subtractor 40 that subtracts a gate voltage of the switching element from a target voltage value; and a constant current circuit 30 that supplies the constant current to the switching element based on the output of the subtractor. Then, the control IC determines that a gate leakage current is generated in the switching element when the supply status based on the monitor signal is different from the switching element at a normal time.SELECTED DRAWING: Figure 1

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