Patent ID: 7385444

Claim:
A class D amplifier comprising: a first PWM waveform generation circuit for generating a PWM waveform according to one signal of differential signals; a second PWM waveform generation circuit for generating a PWM waveform according to the other signal of the differential signals; a logic circuit for outputting AND of an output of the first PWM waveform generation circuit and an inverting output of the second PWM waveform generation circuit; a feedback circuit for feeding back an output of the first PWM waveform generation circuit to the first PWM waveform generation circuit; and a voltage-current conversion circuit for converting an input signal into current and outputting the differential signals, wherein the first and second PWM waveform generation circuits comprise respectively a capacitance element for storing electric charges by the differential signals, the clock signals and feedback signals, a comparison circuit for comparing a potential of the capacitance element and a reference potential and outputting the PWM waveform, and a feedback circuit for converting an output of the comparison circuit into current and feeding it back to the capacitance element.