Title :
Gain-bandwidth product effects on SC filters including a quasi-optimal topology
Author :
Sánchez-sinencio, Edgar
Author_Institution :
Dept. of Electrical Engng., Texas A&M Univ., College Station, TX, USA
Abstract :
The gain-bandwidth product (GB) effects on switched-capacitor (SC) filters are analyzed and described in detail. A systematic general analysis method is reviewed. To biquad SC filters with the same ideal transfer function are compared. It is shown that when the op amps are modeled with one dominant pole, their frequency responses differ significantly. The importance of switch phasing is emphasized and explained, and GB effects on SC filters are discussed. A quasi-optimal SC biquad topology with respect to GB effects is described. Its performance is illustrated by means of a root-locus plot. This plot allows the designer to determine the ω0 and Q deviations for different values of GB/ω0.
Keywords :
active filters; frequency response; linear network analysis; network topology; switched capacitor networks; switched filters; transfer functions; Q-factor deviations; active filters; biquad filters; frequency responses; gain-bandwidth product; linear network analysis; one dominant pole; op amps; operational amplifiers; quasioptimal topology; root-locus plot; switch phasing; switched capacitor filters; transfer function; Capacitors; Clocks; Information filtering; Operational amplifiers; Switches; Topology; Transfer functions;
Journal_Title :
Circuits & Systems Magazine
DOI :
10.1109/MCAS.1983.6323884
