A 1V low power sigma-delta modulator based on floating gate MOS transistors

This paper presents a novel low voltage and low power continuous time sigma-delta modulator based on the floating gate MOS (FGMOS) transistors. The performance of the two main building blocks in the modulator, the continuous time integrator and the comparator, are achieved by exploiting the benefits of the FGMOS devices. It is proven that using FGMOS devices improves the circuit linearity and hence increases the dynamic range. The modulator, designed in AMS 0.35 mum technology, works at a supply voltage of 1 V, exhibits a dynamic range (DR) of 67 dB, signal-to-noise- ratio (SNR) of 63 dB and signal-to-noise-and-distortion-ratio (SNDR) of 60 dB of 2 kHz Bandwidth (BW), with a power consumption of 5 muW.

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