Digital amplifier of 96 kHz PWM frequency with 91dB dynamic range and 0.13% THD+N at full modulation

A Pulse Width Modulation digital amplifier is implemented at 96 kHz of switching frequency, significantly lower than the conventional 384 kHz. This provides numerous advantages: less computational time; lower thermal burden on the output stage power MOSFETs; higher Modulation Index; and lower production cost. The implemented system provides 91dB of Dynamic Range with optimized Noise-Shaper coefficients and satisfies the need of most consumer audio products. The Total Harmonic Distortion + Noise ratio, with the optimized clipping compensation of the NS overflow, is 0.13% at full modulation. The reduced THD+N and switching loss increase the maximum output power at fixed levels of power supply voltage and speaker impedance.

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