Semiconductor apparatus

摘要

A semiconductor apparatus includes a switching device, a voltage detection circuit, a switch circuit, and a control circuit. The voltage detection circuit outputs a detection voltage according to a voltage applied between the first and second terminals of the switching device. The switch circuit is provided in series with a gate drive wire connected to the gate terminal of the switching device and switches between a high impedance state and a low impedance state according to a control signal. The control circuit outputs the control signal to put the switch circuit into the low impedance state when the detection voltage is not greater than a predetermined threshold voltage and outputs the control signal to put the switch circuit into the high impedance state when the detection voltage is greater than the threshold voltage.

主权项

1. A semiconductor apparatus comprising:
a switching device configured to change a conduction state between a first terminal and a second terminal according to a gate voltage applied between a gate terminal and the first terminal; a voltage detection circuit configured to output a detection voltage according to a voltage applied between the first terminal and the second terminal of the switching device; a switch circuit provided in series with a gate drive wire connected to the gate terminal of the switching device and configured to switch between a high impedance state and a low impedance state according to a control signal, and a control circuit having a threshold voltage, the control circuit configured to output the control signal to put the switch circuit into the low impedance state when the detection voltage is not greater than the threshold voltage and configured to output the control signal to put the switch circuit into the high impedance state when the detection voltage is greater than the threshold voltage, wherein the threshold voltage is set less than the detection voltage which the voltage detection circuit outputs when a voltage within a range where a voltage protection operation for the switching device is necessary is applied between the first terminal and the second terminal of the switching device, and the threshold voltage is set greater than the detection voltage which the voltage detection circuit outputs when a voltage within a range where the voltage protection operation for the switching device is unnecessary is applied between the first terminal and the second terminal of the switching device.