Abstract: A semiconductor device having an input terminal and an output terminal. The semiconductor device includes a power semiconductor element having a first main terminal connected to the output terminal, a second main terminal that is grounded and a gate terminal, and an active clamping circuit including a Zener diode and a diode connected in inverse series between the gate terminal and the first main terminal of the power semiconductor element. The semiconductor device further includes a clamp voltage switching circuit configured to switch a clamp voltage of the active clamping circuit according to a change in a voltage of the output terminal relative to the ground at a time when the power semiconductor element is turned off, the clamp voltage being switched to a first clamp voltage and a second clamp voltage, respectively, when the change in the voltage is not, and is, positive.

Abstract: A semiconductor device having an input terminal and an output terminal. The semiconductor device includes a power semiconductor element having a first main terminal connected to the output terminal, a second main terminal that is grounded and a gate terminal, and an active clamping circuit including a Zener diode and a diode connected in inverse series between the gate terminal and the first main terminal of the power semiconductor element. The semiconductor device further includes a clamp voltage switching circuit configured to switch a clamp voltage of the active clamping circuit according to a change in a voltage of the output terminal relative to the ground at a time when the power semiconductor element is turned off, the clamp voltage being switched to a first clamp voltage and a second clamp voltage, respectively, when the change in the voltage is not, and is, positive.

Abstract: An insulated-gate type device driving circuit for driving an insulated-gate semiconductor element based on a gate signal inputted from the outside includes a gate voltage control semiconductor element which is connected between a gate and a source of the insulated-gate semiconductor element, and a pull-up element which is constituted by a depletion type MOSFET connected between a gate and a drain of the gate voltage control semiconductor element. The gate voltage control semiconductor element is driven by a voltage applied to the gate of the insulated-gate semiconductor element, and a back gate of the MOSFET constituting the pull-up element is grounded to prevent a parasitic transistor from being formed.

Abstract: An insulated-gate type device driving circuit for driving an insulated-gate semiconductor element based on a gate signal inputted from the outside includes a gate voltage control semiconductor element which is connected between a gate and a source of the insulated-gate semiconductor element, and a pull-up element which is constituted by a depletion type MOSFET connected between a gate and a drain of the gate voltage control semiconductor element. The gate voltage control semiconductor element is driven by a voltage applied to the gate of the insulated-gate semiconductor element, and a back gate of the MOSFET constituting the pull-up element is grounded to prevent a parasitic transistor from being formed.