Patent ID: 7960937

Claim:
An inverter unit for controlling an AC motor, the unit comprising: an inverter circuit section including a plurality of high breakdown voltage semiconductor elements; an integrated circuit chip including a first circuit section for controlling operating timing of the plurality of high breakdown voltage semiconductor elements and a second circuit section for outputting drive signals for driving the plurality of high breakdown voltage semiconductor elements according to the operating timing and for feeding back an abnormality of the inverter circuit section to the first circuit section formed on an SOI substrate; a level shifter provided between circuit formation areas; and a pulse generation circuit that converts a signal received from a circuit formation area to which a first power supply voltage is applied, into a one-shot pulse of a reference voltage that is different from a reference voltage of the signal, and inputs the one-shot pulse to the level shifter provided on a path that carries the signal from the circuit formation area to a circuit formation area to which a second power supply voltage higher than the first power voltage is applied, and wherein the circuit formation areas which differ in reference potential are separated from one another by dielectrics, and the dielectrics are separated from one another and surround the respective circuit formation areas.