A phase-shift self-oscillating stereo class-D amplifier for battery-powered applications

Alexandre Huffenus , Gaël Pillonnet (1) , Nacer Abouchi (1) , Frédéric Goutti (2) , Vincent Rabary (2) , Cécile Specq (2)

1 INL - CSH - INL - Conception de Systèmes Hétérogènes
2 STMicroelectronics

This paper presents a highly efficient stereo audio amplifier, based on a self-oscillating modulator. This modulation scheme has been analyzed and shows to have a higher bandwidth and error correction than standard Pulse Width Modulation (PWM). A practical implementation in CMOS 0.25um technology has been done to validate our theoretical and simulation results. Our amplifier demonstrated a Total Harmonic Distortion plus Noise (THD+N) as low as 0.07%, current consumption is 3.88mA at 3.6V (stereo) and the efficiency reaches 88% into 8Ohms. The integrated circuit measures 1.6x1.6mm and is able to work at supply voltages from 2.3V to 5.5V.

Domaines: Sciences de l'ingénieur [physics]

Alexandre Huffenus, Gaël Pillonnet, Nacer Abouchi, Frédéric Goutti, Vincent Rabary, et al.. A phase-shift self-oscillating stereo class-D amplifier for battery-powered applications. IEEE International Symposium on Circuits and Systems, IEEE, 2010, Paris, France. pp.4, ⟨10.1109/ISCAS.2010.5537458⟩. ⟨hal-01103679⟩