Optimal design of delta-sigma ADCs by design space exploration

An algorithm for architecture-level exploration of ΔΣ ADC design space is presented. The algorithm finds an optimal solution by exhaustively exploring both single-loop and cascaded architectures, with single-bit or multi-bit quantizer, for a range of oversampling ratios. A fast filter-level step evaluates the performance of all loop-filter topologies and passes the accepted solutions to the architecture-level optimization step which maps the filters on feasible architectures and evaluates their performance. The power consumption of each accepted architecture is estimated and the best top-ten solutions in terms of the ratio of peak SNDR versus power consumption are further optimized for yield. Experimental results for two different design targets are presented. They show that previously published solutions are among the best architectures for a given target but that better solutions can be designed.