A motor driving apparatus has first, second, and third positive-side driving transistors having drains which are supplied with a power supply voltage, first, second, and third negative-side driving transistors having sources which are grounded and drains which are connected to sources of the first, second, and third positive-side driving transistors, respectively, a power supply monitoring circuit which monitors the power supply voltage and outputs a driving mode switching signal which has a first value if the power supply voltage is not less than a predetermined value and has a second value if the power supply voltage is less than the predetermined value, and an output PWM control section which switches a mode of driving from synchronous rectification PWM driving to one-way PWM driving on the basis of a change of the driving mode switching signal from the second value to the first value.