Electronic International Standard Serial Number (EISSN)
1350-911X
abstract
A new sigma delta (SigmaDelta) modulator suitable for ultra-low power dataconverters is introduced. The proposed architecture is based on timeencoding and quantisation using voltage controlled delays such asdigital inverters. The delays together with a phase comparatorimplement a synchronous pulse width modulator (PWM) and a discretetime integrator. An additional analogue integrator provides secondordernoise shaping and compensates the nonlinearity of the digitaldelay. Time quantisation of the two-level PWM signal allows implementinga multibit modulator without requiring linear multibit DACs.