Patent ID: 8022477

Claim:
A semiconductor apparatus comprising: a semiconductor substrate; a lateral type MIS transistor that is disposed on a surface part of the semiconductor substrate; a line for a gate drive signal, the line connecting a gate electrode of the lateral type MIS transistor to a drive voltage production circuit; a polycrystalline silicon resistor that is inserted in the line so that the drive voltage production circuit, the polycrystalline silicon resistor, and the gate electrode are connected in series with each other, and that has a conductivity type opposite to a conductivity type of a drain of the lateral type MIS transistor, wherein the drain includes a drain region and a drift region; and an insulating layer via which the polycrystalline silicon resistor and the drain of the lateral type MIS transistor are disposed opposite to each other so that an electric potential of the drain acts on the polycrystalline silicon resistor through the insulating layer to spread a depletion layer in the polycrystalline silicon resistor, the depletion layer increasing a resistance of the polycrystalline silicon resistor between the gate electrode and the drive voltage production circuit.