Single-Input Four-Output Voltage-Mode Universal Biquadratic Filter Employing Four OTAs and Two Grounded Capacitors

This paper presents a new single-input four-output electronically tunable voltage-mode biquadratic filter employing five operational transconductance amplifiers and two grounded capacitors. The proposed filter provides lowpass, band-pass, high-pass and band-stop voltage responses without changing the input and output terminal connections. The natural frequency and the quality factor can be set orthogonally by adjusting the circuit components. Also, the proposed filter provides high input impedance which can be directly connected in cascade to apply higher-order filters. No inverting-type input signals are required for the realizing of all the filter responses and all the active and passive sensitivities are low. Simulation results verifying the performances of the proposed circuit are also included.