Versatile second order filter structures for low-voltage multiple-input amplifiers

Abstract

Two second order filter architectures are presented with applications to double and single ended multiple input amplifier configurations. These circuits can be configured to perform BP, HP, LP and notch filter functions. The Gm tunability of the fully-complementary, Composite Folded Cascode (CFC) based amplifier test structures is achieved by a MOSR scheme with center-frequency variations in the upper Megahertz range, using power supplies of /spl plusmn/2.5 V.