Stability analysis and system design of sigma-delta modulators

A system design with new empirical stability criteria for sigma-delta modulators is proposed. The stability criteria is a cubic function obtained by the least square method, and simulations including coefficients variation due to component mismatches of circuit implementation are included. By using the proposed methodology, several stability criteria of different targets (e.g., architectures, oversampling ratios (OSRs), and multi-bit) are found.