TableBased Simulation of DeltaSigma Modulators

The program ZSIM (nonlinear Z-domain SIMulator) is used to explore the benefits and limitations of a table-based approach to the simulation of delta-sigma modulators with switched-capacitor integrators. Simulations demonstrating the effects of clock feedthrough and incomplete settling are presented, as wen as simulations demonstrating the importance of the use of an accurate and charge conservative circuit simulator for the table point transient simulations. The methods used are appropriate for other discrete time systems where simulation of system-level perfonnance is desired based on the results of transient circuit simulation.