MATLAB/Simulink modeling of offset and flicker noise in Delta-Sigma modulators has been developed, providing a fast tool for the estimation of ADC performances. Since high accuracy and resolution are fundamental in sensor applications, a brief analysis of the main noise sources in second order Delta-Sigma modulators is presented, together with the typical solutions found in the literature. Generalization of system-level chopper technique for the rejection of the converter overall offset and low-frequency noise has been proposed and their effectiveness is evaluated by means of high-level simulations.