Title :
Noise-shaping modulation in high-Q SC filters
Author :
Ausín, J.L. ; Domínguez, M.A. ; Duque-Carrillo, J.F. ; Torell, G.
Author_Institution :
Dept. of Electron. & Electr. Eng., Univ. de Extremadura, Badajoz, Spain
Abstract :
A low-cost tuning scheme for programmable second-order switched-capacitor filters that use partial positive feedback to achieve high Q values, is presented. In this scheme, a noise-shaping feedback coder controls the positive feedback amount in a local loop. Automatic Q-factor tuning is performed by measuring the ratio of a pair of capacitors. Simulation results considering a 0.8-μm CMOS process are presented to verify the feasibility of the proposed approach in integrated circuit design.
Keywords :
CMOS analogue integrated circuits; Q-factor; circuit feedback; circuit tuning; integrated circuit noise; programmable filters; switched capacitor filters; 0.8 micron; CMOS integrated circuit; automatic Q-factor tuning; noise-shaping modulation; positive feedback; programmable second-order switched-capacitor filter; Automatic control; Capacitors; Circuit optimization; Circuit simulation; Feedback loop; Filters; Integrated circuit measurements; Noise shaping; Performance evaluation; Q factor;
Conference_Titel :
Circuits and Systems, 2003. ISCAS '03. Proceedings of the 2003 International Symposium on
Print_ISBN :
0-7803-7761-3
DOI :
10.1109/ISCAS.2003.1205634
