Patent ID: 7436042

Claim:
A circuit for driving a gate of a power metal-oxide semiconductor field effect transistor (MOSFET) in a digital audio amplifier including a power PMOSFET transistor in which a first power source voltage is applied to a source and an output terminal is connected to a drain; a power NMOSFET transistor in which the output terminal is connected to a drain and a second power source voltage is applied to a source; a gate controller which uses a third power source voltage which is lower than the first power source voltage and a fourth power source voltage which is lower than the second power source voltage, and controls gates of the power PMOSFET and NMOSFET transistors; and an output filter which is connected to the output terminal and has an inductor and a capacitor, the circuit comprising: a first resistance connected between the first power source voltage and the gate of the power PMOSFET transistor; a second resistance connected between the second power source voltage and the gate of the power NMOSFET transistor; a first capacitor connected between an output terminal of the gate controller and the gate of the power PMOSFET transistor; a second capacitor connected between the output terminal of the gate controller and the gate of the power NMOSFET transistor; a first diode connected between the output terminal of the gate controller and the gate of the power PMOSFET transistor; and a second diode connected between the output terminal of the gate controller and the gate of the power NMOSFET transistor.