Distortion and its suppression in low-power delta-sigma modulator

In this paper, effects of amplifier distortion in DT sigma-delta modulator are discussed. A second order modulator with single-bit quantizer is modeled and dead-zone effect of ring amplifiers in integrators is simulated by using MATLAB. For the evaluation of dead-zone effect on modulator distortion, test chip was fabricated in 65nm CMOS. SNDR of 62dB and 1MHz signal bandwidth was experimentally demonstrated at sampling frequency of 102.4MHz and power consumption of 1mW.