Impact of VCO non-linearities on VCO-based sigma-delta modulator ADCs

Abstract

In this paper, the effects of non-linearities and phase noise in a voltage-controlled oscillator on the performance of VCO-based Continuous Time First-Order Delta-Sigma Modulator Analog-to-Digital Converter are studied. A test circuit was implemented MATLAB/Simulink model and data extrapolated from two different 25-ring VCOs designed and simulated in Spectre environment.