A dual-level dual-phase pulse-width modulation class-D amplifier with 0.001% THD, 112 dB SNR

This paper presents a dual-level dual-phase pulse-width modulation (DLDP PWM) Class-D audio amplifier circuit which enhance amplifier linearity and reduce distortion. The proposed DLDP PWM Class-D audio amplifier includes two sets of non-overlapping triangular waves, each at its respectful offset levels. Each set of triangular waves is composed of two 180° out-of-phase triangular waves. The differential power stage consists of 8 power transistors, with voltage swings up to +/- 6V. Simulated results shows that the proposed DLDP PWM Class-D audio amplifier features an SNR up to 105 dB, and the THD is suppressed below 0.001 %, with the 3rd harmonic below -102 dBV.