Delta-sigma modulator with large OSR using the one-hot residue number system
William A. Chren · IEEE Transactions on Circuits and Systems II Analog and Digital Signal Processing · 1999
A digital delta-sigma modulator using the one-hot residue number system (OHRNS) is presented. It exhibits a large oversampling ratio (OSR) in comparison with equivalent binary designs. Its second-order architecture employs a two-stage cascade structure with two-level internal and four-level output quantization. It is intended for use in a high-resolution interpolative digital-to analog converter. Analytical estimates show a significant improvement in OSR and latency over binary-number system-based designs. These benefits are made possible by the use of the (OHRNS), which allows addition and multiplication to be performed equally quickly and simply, using barrel shifters and signal transposition. An application specific integrated circuit (ASIC) implementation of the design is also presented in a 2-/spl mu/m CMOS technology.