PAPER SESSION 2: POWER STAGE TOPOLOGIES
2-3 Self-Oscillating Modulators for Direct Energy
Conversion Audio Power Amplifiers
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.