High input impedance voltage-mode lowpass, bandpass, highpass and notch filter using current feedback amplifiers

Abstract

The paper presents a new voltage-mode (VM) high input impedance filter having a single input and four low impedance outputs. The proposed circuit employs four current feedback amplifiers (CFAs) and six passive elements, four of them are grounded and enjoys the following advantages: simultaneous realisation of lowpass (LP), bandpass (BP), highpass (HP) and notch filtering functions explicitly, cascadability, independent control of resonance frequency (<i style="">w₀</i>)and bandwidth (<i style="">w₀/Q</i>), orthogonal control of resonance frequency (<i style="">w₀</i>) andquality factor (<i style="">Q</i>), no requirements for component matching conditions, use of two grounded capacitors which are ideal for IC implementation and low passive sensitivity figures. Experimental and PSPICE simulation results are given to verify the theoretical calculations.