An optimal design method of delta-sigma modulator using GA for digital audio amplifier

Low-power digital audio (Class-D) amplifiers are widely used in portable digital devices, such as MP3 players and smart phones. ΔΣ modulators are suitable for Class-D amplifiers, because high-order modulators provide better performance and low cost. However, for higher-order ΔΣ modulator design, it is imperative to determine the optimal design parameters for realizing the maximum signal-to-noise ratio (SNR) while maintaining system stability. This process requires the expertise of an experienced designer. To avoid this requirement, we propose an automatic optimal design method that uses genetic algorithm (GA) and that does not require the expertise of an experienced designer. This method generates an optimal design of ΔΣ modulators, so that the design provides higher system stability and maintains high SNR.