Title :
Continuous time Δ Σ modulation with PWM pre-coding and binary gm blocks
Author :
Babaie Fishani, A. ; Rombouts, P.
Author_Institution :
ELIS, Univ. of Gent, Ghent, Belgium
Abstract :
A very simple technique to implement the first integrator of a continuous-time delta sigma modulator (CT-DSM) is presented. In the approach, the CT-DSM is preceded by a pulse-width modulator to convert the input signal to a pseudo-digital continuous time waveform. As a result, the first integrator of the DSM can be implemented with a capacitor and a switched current source, with inherent linearity. To illustrate the concept, it has been applied to the design of a second-order CT-DSM in 65 nm CMOS technology.
Keywords :
CMOS integrated circuits; capacitors; constant current sources; continuous time systems; delta-sigma modulation; integrating circuits; modulators; precoding; pulse width modulation; CMOS technology; PWM precoding; binary gm blocks; capacitor; continuous time ΔΣ modulation; continuous time delta sigma modulator; first CT-DSM integrator implement; input signal conversion; pseudodigital continuous time waveform; pulse width modulator; second-order CT-DSM design; size 65 nm; switched current source;
Journal_Title :
Electronics Letters
DOI :
10.1049/el.2012.2697