A 4th-Order Wideband Sigma Delta Modulator Using Linear System Theory Technique

Abstract

A 4th-Order Wideband Sigma Delta modulator structure is proposed in this paper, which uses linear system theory technique. There are many implementation techniques to improve the performance of Sigma Delta ADCs, such as noise coupling, differential sampling and dynamic elements matching. An extra loop delay is needed to be added in the system. This paper explains how to make the modulator stable with the addition of feed-forward and feed-back branches which are used to compensate the extra loop delay. Next, we restore the signal and noise transfer functions. A 4th-Order Wideband delta- sigma modulator have been designed and simulated to verify the method. 2016 SERSC.