This paper presents the analysis of Delta sigma modulators. First order, second order, third order and a 2-1 cascaded modulator are presented here. The higher the order of modulator higher is the order of noise shaping offered by the design but higher order modulators suffer from potential instability. For this reason cascaded and mash designs are considered. Cascaded designs have less Snr but are more stable as compared to higher order non cascaded modulators.