Reducing quantization noise with recursive /spl Sigma//spl Delta/ modulators

This paper introduces a recursive multibit /spl Sigma//spl Delta/ architecture that enables a high effective quantizer resolution while needing only a limited number of DAC elements. The recursive architecture consists of a set of /spl Sigma//spl Delta/ modulators, whereby each stage cancels the quantization noise of the proceeding stage. Conventional DEM algorithms can be used in each stage to reduce the sensitivity to mismatch. The architecture enables a significant reduction of both the signal-band and out-of-band quantization noise power, compared to conventional multibit /spl Sigma//spl Delta/ converters.