In recent years, oversampled data converters have been employed for telecommunication and voice applications. Their reduced sensitivity to circuit imperfections makes them more tolerable to changes in technology parameters and mismatch. In order to optimize the set of architecture and parameters, system simulation is necessary to reach high performance. In this paper, the design criteria of a sigma-delta (Sigma-Delta) converter are indicated adopting both Matlab and VHDL-AMS. The analysis is carried out taking into account circuit parameter variations and investigating aspects such as accuracy, flexibility and performance