A comparator with reduced regeneration time for continuous-time delta-sigma modulator

A design of a comparator with reduced regeneration time and down scaling voltage for continuous-time delta-sigma modulators (CT DSM) was proposed. It has voltage scaling down to 0.65 V, and gives worst case delay under 10%Ts (i.e. 125 ps for 800 MHz sampling frequency) at 1.2 V supply voltage. A 3 rd order low pass CT DSM employing the proposed comparator achieves 50.76 dB of SNDR and 3.2 MHz bandwidth, which are 5.2 dB higher and 3.2 times wider than those of a 3 rd order low pass CT DSM employing the reference comparator, respectively.