Patent ID: 8299737

Claim:
A motor driving circuit, comprising: a three-phase inverter circuit, including three upper-arm switching elements for driving upper arms of different phases of the three-phase motor, and three lower-arm switching elements for driving lower arms of different phases, at least one of the lower-arm switching elements and the upper-arm switching elements is a semiconductor element, including a semiconductor layer stack made of nitride semiconductor layers formed on a substrate, a first ohmic electrode and a second ohmic electrode formed on the semiconductor layer stack spaced apart from each other, and a first gate electrode formed between the first ohmic electrode and the second ohmic electrode, wherein the semiconductor element performs a diode operation in which a voltage less than or equal to a threshold voltage of the first gate electrode is applied to the first gate electrode with reference to a potential of the first ohmic electrode, thereby conducting a current flow from the first ohmic electrode to the second ohmic electrode and blocking a current flow from the second ohmic electrode to the first ohmic electrode.