The Correction Method for Power Noise in Digital Class D Power Amplifiers

In a digital class D power amplifier, the distortion is introduced into the input signal being amplified in power stage, due to the effect of power supply noise. A method used to eliminate the distortion is presented in the paper. This method is adding correction factors to all integrators of Delta-Sigma modulator, and introducing power supply noise to the input of the class D power amplifier and Delta-Sigma modulator. A design example with the method is presented, and the simulation results indicate this method can eliminate the error introduced by power stage.