Linear and nonlinear modeling of switched-capacitor Δ∑ modulators

A new methodology is presented for both linear and nonlinear circuit-level modeling of switched-capacitor Δ∑ modulators. It takes account of the MOSFET parasitic capacitances, switch on-resistances, opamp gain-bandwidth products, the nonlinear behavior of the parasitic capacitances and opamps, clock jitter, etc. Mathematically, a system of circuit equations is constructed by nodal analysis in the frequency domain, and its solutions in the form of Volterra series are mapped into the time domain by numerical Laplace inversion. The methodology can be used for nonlinear-distortion analysis. It is implemented in software within MATLAB. © Nauka/Interperiodica 2007.