Title :
A 3.3 V switched-current second order sigma-delta modulator for audio applications
Author :
Loulou, M. ; Dallet, D. ; Marchegay, P.
Author_Institution :
Lab. de Microelectron., CNRS, Talence, France
Abstract :
This paper presents a low pass sigma-delta modulator (ΣΔ) for Analog-to-Digital conversion which uses the switched-current technique. The growth of this technique is limited by the clock feedthrough which induces an error on the output signal value. In order to cancel the effect of this phenomena a new method based on a current feedback loop is used. The ΣΔ modulator implemented is a conventional second order and the whole circuit is designed with fully differential current mode building blocks. The circuit, designed in 0.8 μm AMS single poly CMOS process, shows 55 dB dynamic range at 2 MHz sampling rate with 8 kHz input frequency bandwidth
Keywords :
CMOS integrated circuits; compensation; integrating circuits; network synthesis; sigma-delta modulation; switched current circuits; 0.8 μm AMS; 0.8 mum; 2 MHz; 2 MHz sampling rate; 3.3 V; 55 dB; 55 dB dynamic range; 8 kHz; 8 kHz input frequency bandwidth; analog-to-digital conversion; audio applications; clock feedthrough; current feedback loop; differential current mode building blocks; poly CMOS process; sigma-delta modulator; switched-current modulator; switched-current technique; Analog-digital conversion; Bandwidth; CMOS process; Circuits; Clocks; Delta-sigma modulation; Dynamic range; Feedback loop; Frequency; Sampling methods;
Conference_Titel :
Circuits and Systems, 2000. Proceedings. ISCAS 2000 Geneva. The 2000 IEEE International Symposium on
Conference_Location :
Geneva
Print_ISBN :
0-7803-5482-6
DOI :
10.1109/ISCAS.2000.858775
