Motor driving circuit

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.