New realization of multifunction filters without using external passive elements

Abstract

New voltage-mode multifunction filters using operational transconductance amplifiers (OTAs) and internally compensated operational amplifiers (OP-AMPs) are presented. The first proposed voltage mode multifunction filter can realize highpass and bandpass responses and the second proposed voltage mode multifunction filter can realize bandpass, lowpass and bandstop responses simultaneously. No external passive elements are required; thus the circuit is suitable for monolithic implementation either with CMOS or bipolar technologies. All of the sensitivities are low. The performances of the circuits are tested using the SPICE simulation program.