Very Low-voltage Digital-Audio Delta Sigma Modulator with 88-dB Dynamic Range using Local Switch Bootstrapping

Mohamed Dessouky (1) , Andreas Kaiser

1 ASIM - Architecture des Systèmes intégrés et Micro électronique

A 1-V 1-mW 14-bit ΔΣ modulator in a standard CMOS 0.35-μm technology is presented. Special attention has been given to device reliability and power consumption in a switched-capacitor implementation. A locally bootstrapped symmetrical switch that avoids gate dielectric overstress is used in order to allow rail-to-rail signal switching. The switch constant overdrive also enhances considerably circuit linearity. Modulator coefficients of a single-loop third-order topology have been optimized for low power. Further reduction in the power consumption is obtained through a modified two-stage opamp. Measurement results show that for an oversampling ratio of 100, the modulator achieves a dynamic range of 88 dB, a peak signal-to-noise ratio of 87 dB and a peak signal-to-noise-plus-distortion ratio of 85 dB in a signal bandwidth of 25 kHz

Domaines: Informatique [cs]

Mohamed Dessouky, Andreas Kaiser. Very Low-voltage Digital-Audio Delta Sigma Modulator with 88-dB Dynamic Range using Local Switch Bootstrapping. IEEE Journal of Solid-State Circuits, 2001, 36 (3), pp.349-355. ⟨10.1109/4.910473⟩. ⟨hal-01197325⟩