A cascaded continuous-time ΣΔ modulator with 67dB dynamic range in 10MHz bandwidth

Abstract

A 2-2 cascaded /spl Sigma//spl Delta/ modulator with continuous-time loop filters and 4b quantizers is presented. The dynamic range is 67dB in a 10MHz bandwidth at a 160MS/s with a full-scale input range of 200mV/sub rms/. Inherent anti-aliasing filtering is over 50dB. The 0.18/spl mu/m CMOS chip measures 1.7mm/sup 2/ and draws 68mA from a 1.8V supply.