Patent ID: 7002406
Filing Date: 2006-02-21
Classification: H03F

Abstract:
1. A class D amplifier circuit, comprising: an adder, for generating a difference signal responsive to an input signal and a feedback signal; a pulse-width-modulator, for comparing the difference signal to a waveform having a switching frequency, and for generating a pulse-width-modulated output signal responsive to the result of the comparing; a power stage, for driving its output responsive to the pulse-width-modulated output signal; and a loop filter, coupled to the output of the power stage, for generating the feedback signal by applying a minimum-aliasing-error transfer function to a signal from the output of the power stage, the minimum-aliasing-error transfer function being a minimum of second order, and having a time-domain impulse response that has a time-domain impulse response h(t) having a slope that is substantially zero for small positive values of t.