27th International AES Conference


2-3 Self-Oscillating Modulators for Direct Energy Conversion Audio Power Amplifiers

Petar Ljusev, Michael A. E. Andersen. Technical University of Denmark, Lyngby, Denmark.

Direct energy conversion of an audio power amplifier represents the total integration of a switching-mode power supply and class D audio power amplifier into one compact stage, achieving high efficiency, high level of integration, low component count, and eventually low cost. This paper presents how self-oscillating modulators can be used with the direct switching-mode audio power amplifier to improve its performance by providing fast hysteretic control with high power supply rejection ratio, open-loop stability, and high bandwidth. Its operation is thoroughly analyzed, and experimental results from a prototype amplifier are presented.

Conference sponsors: