Self-Oscillating Class-D Audio Amplifier With A Phase-Shifting Filter in Feedback Loop
نویسندگان
چکیده
A self-oscillating class-D audio amplifier adopting the phase-shifting looap filter in the feedback filter is proposed. To validate the design, a mathematical model is proposed. It is alleged in a very simple form which describes the switching frequency variation as the function of the modulation depth to be applied to any general structure: phase shifting, time delay of the loop, and the hysteresis window at the comparator. The main focus is set on the analysis of the phase-shifting filter which shows the least dependency on the modulation depth.
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