Low power 3rd order feedforward sigma delta ADC design

: In this work, a 3-bit feedforward 3rd order sigma delta analog-to-digital converter (ADC) is presented. In this proposed architecture, feedforward paths and multibit design help the integrator output swings to become smaller, which renders the exploitation of a telescopic cascode opamp in the integrators possible. Moreover, a double sampling method is used to relax the opamp specifications. The proposed sigma delta ADC consumes 28.2 µW and has 81.3 dB SNDR according to postlayout simulations.

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