Based Second Order ∑Δ Modulator for Digital Hearing Aid Applications

Abstract This paper describes the design and simulation of a sigma delta modulator (∑ΔM) architecture that can be used in digital hearing aid applications. A model of a non-ideal second order feed-forward ∑Δ Modulator, adopted for this purpose, is also presented. The loop coefficients of this architecture are optimized using Genetic Algorithm. The architecture together with optimized coefficients achieves 99 dB SNDR and a dynamic range of 101 dB. A sampling frequency (fs) of 1.28 MHz and a second order modulator makes this architecture less complex and power efficient.

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