Low input impedance current driven multifunction active filter with voltage outputs

Abstract

In this paper a new trans-impedance mode multifunction filter using only active elements is presented. The proposed circuit is composed of three internally compensated operational amplifiers (OAs) and three single-output operational transconductance amplifiers (OTAs), without using any external passive elements. The proposed multifunction filter can realize lowpass, bandpass and highpass responses simultaneously. No matching condition is required. The circuit is suitable for monolithic implementation either with CMOS or bipolar technologies. All of active sensitivities are low. The performance of the circuit is tested using SPICE simulation program.