New high output-impedance current-mode multifunction filters in a 0.5 ?m CMOS

Abstract

In this paper two new current-mode multifunction filters are presented. The proposed circuits are composed of two internally compensated operational amplifiers (OAs) and three dual-output operational transconductance amplifiers (OTAs), without using external passive elements. Each proposed multifunction filter can realize band-pass, bandstop, and lowpass or highpass responses simultaneously all at high output impedances. No matching conditions are required. The circuits are suitable for monolithic implementation either with CMOS or bipolar technologies. All of active sensitivities are low. The performances of the circuits are confirmed through a SPICE simulation program using the model parameters of 0.5 mum MIETEC CMOS technology.