Fast simulation of bandpass continuous-time ΣΔ modulators

A methodology for the simulation of bandpass continuous time sigma-delta (SigmaDelta) modulators is presented in this paper. This method permits the simulation of SigmaDelta modulators employing continuous-time filters using a fixed-step algorithm. The method is based on the discretization of a continuous-time model and the use of a discrete simulator, which is more efficient than an analog simulator. This transformation is exact in term of noise transfer function and asymptotically exact in term of signal transfer function (the signal transfer function of the model rapidly tends to the continuous time model transfer function when the number of steps increases).