Self-coupled MASH Delta-Sigma Modulator with Zero Optimization

This paper presents a discrete time (DT) self-coupled multi-stage noise-shaping (MASH) delta-sigma modulator (DSM) with zero optimization. Zero optimization scheme is incorporated into the self-coupled path between the MASH stages, thus generating a desired notch in the band edge for the leaked quantization noise. When compared with a general self-coupled path, the employment of zero optimization can further mitigate the quantization noise leakage. Moreover, this zero-optimization scheme can be easily implemented by changing the coefficient of the self-coupled path. Therefore, it does not impose any additional hardware consumption. A 2+2 MASH DSM was built in the Matlab Simulink to demonstrate its principle. Simulation results show that the proposed architecture relaxed the DC gain requirements for the integrators further.