Harmonic distortion in fully-differential switched-current sigma-delta modulators

Abstract

This paper presents a systematic analysis of the harmonic distortion in XA modulators (XAMs) implemented with fully-differential switched-current (SI) circuits. Closed form expressions are derived for the third-order harmonic distortion in lowpass and bandpass XAMs. For the latter, the third-order intermodulation distortion is also deduced. Time domain behavioral simulations validate our approach.(*)