A 0.18-µm CMOS, −92-dB THD, 105-dBA DR, third-order audio class-D amplifier

Abstract

This paper presents a third-order audio class-D amplifier, implemented in a 0.18-μm CMOS technology, achieving -92 dB of total harmonic distortion (THD) and 105 dBA of dynamic range (DR) with a quiescent current of 2 mA. The circuit delivers up to 2.4 W on a 4-Ω load with a peak efficiency of 88%. The THD performance, achieved thanks to the third-order loop filter, makes the proposed device suitable for high-end audio applications, where linear amplifiers are still the dominant solution.