Voltage-mode versatile biquadratic filter with three-input three-output using four OTAs, one CCII and two capacitors

This paper presents a new electronically tunable versatile voltage-mode biquadratic filter with three inputs and three outputs using four operational transconductance amplifiers, one current conveyor and two grounded capacitors. The proposed circuit can realize second-order low-pass, band-pass, high-pass, band-stop and all-pass filters by appropriately connecting the input and output terminals. The natural frequency and the quality factor can be set orthogonally by the circuit components. Also the natural frequency can be electronically controlled. For realizing all the filter responses, no component-matching conditions are required. The active and passive sensitivities are low and the input-impedances are high. PSPICE simulation results are given to confirm the presented theory.