Class D Audio Amplifier with Reduced Distortion

In this paper, the design and the implementation of the low-voltage class D audio amplifier is presented. The amplifier topology with reduced distortion, based on the Pulse Density Modulation (PDM) technique, is proposed. The verification of the proposed amplifier was done by measuring the Total Harmonic Distortion factor (THD) for the different resistance values in the feedback circuit, as well as for the different frequencies of the input audio signal and the switching signal. It is shown that one of the implementations has THD factor under 1%.