Single fully differential current feedback operational amplifier (FDCFOA) biquads with positive feedback topology

Abstract

New configuration for the design of biquad filters with positive feedback topology is presented. Theconfiguration can synthesize low-pass, high-pass and band-pass filter functions according to thepassive components used in circuits. The proposed configuration employs only one FDCFOA asactive element and minimum number of passive elements, namely two capacitors and resistors. SPICEsimulation results are given to confirm the validity of the analysis and to point out the highperformance of the filters. The output of the filter exhibits high output impedance so that thesynthesized filter can be cascaded without additional buffers.