On the Optimization of DT Incremental Sigma-Delta Modulators in Combination with CoI Reconstruction Filters

In this paper the optimization of discrete-time incremental ΣΔ modulators in combination with chain-of-integrators reconstruction filters is described. In the state-of-the-art, the modulator and reconstruction filter part of an incremental ΣΔ ADC is usually designed separately, not necessarily leading to the best possible performance. By extending the automated design tool www.sigma-delta.de for the support of incremental ΣΔ ADCs, the modulator part can be optimized with regard to the reconstruction filter. It is shown that the performance of an incremental ΣΔ ADC can benefit from this combined optimization compared to an ADC consisting of a modulator optimized independently from the reconstruction filter. Moreover, the reproducibility of the optimization results can be improved.