Patent ID: 9490793
Filing Date: 2016-11-08
CPC Classification: H01L,H03K

Claim Text:
1. An insulated-gate type device driving circuit for driving an insulated-gate semiconductor element based on a gate signal inputted from outside, comprising: a gate voltage control semiconductor element which is connected between a gate and a source of the insulated-gate semiconductor element; 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; a threshold control circuit which controls driving of the gate voltage control semiconductor element based on the gate signal; and a diode which prevents a current from flowing into a high potential side power supply of the threshold control circuit from the pull-up element; wherein: the gate voltage control semiconductor element is driven by a voltage applied to the gate of the insulated-gate semiconductor element; a back gate of the depletion type MOSFET constituting the pull-up element is grounded; and the threshold control circuit has a series circuit, which is connected between the gate and the source of the insulated-gate semiconductor element, of an N-type depletion MOSFET, a diode and an N-type enhancement MOSFET, and a connection point between the diode and the N-type enhancement MOSFET is connected to a connection point between the pull-up element and the gate voltage control semiconductor element.