A buck converter for use in controlling a motor in accordance with an embodiment of the present invention includes a power input operable for connection to a DC power supply, a switch for selectively connecting the motor to the power supply, a pulse width modulation controller operable to provide a pulse width modulation signal to the switch, wherein the switch connects the motor to the power supply based on the pulse width modulation signal, and a voltage shifting capacitor connected across the switch and in series with a diode. The buck converter may include a shift control device operable to control a voltage across the voltage shifting capacitor.