Sigma-delta modulator using a local nonlinear feedback loop technique

摘要

A local nonlinear feedback loop (LNFL) technique and a sigma-delta modulator (SDM) for promoting highly stable oversampling using the LNFL technique. Not only can gain mismatch of the sigma-delta modulator be minimized, but the overload of the later stage sigma-delta modulator can also be resolved without sacrificing the signal noise ratios (SNR) of the overall system. Moreover, using the local nonlinear feedback loop technique of this invention attenuates the voltage signal of the sigma-delta modulator, therefore decreasing the power consumption of the overall sigma-delta modulator system.