A sigma-delta modulator with a novel chopper correlated double sampled integrator

This paper presents a fully differential second-order Sigma-Delta modulator (SDM) based on a chopper correlated double sampled integrator. The Correlated double sampling technique (CDS) and chopper stabilization technique (CHS) are used in the first integrator to eliminate the low frequency noise of the amplifier. The whole circuit implemented in a 0.35 um CMOS technology with 3.3V supply voltage. The simulation results show that the proposed SDM has better performance on eliminating the contamination of the low frequency noise of the amplifier than traditional CDS modulator.