An electronically controllable dual-mode universal biquad filter using only single CCCCTA

This article presents a dual-mode (voltage-mode and current-mode) universal biquadratic filter performing completely standard functions: low-pass, high-pass, band-pass, band-reject and all-pass functions, based on plus type dual-output current controlled current conveyor transconductance amplifier (CCCCTA). The features of the circuit are that: the quality factor and natural frequency can be tuned electronically via the input bias currents: the circuit description is very simple, consisting of merely single CCCCTA and 2 capacitors: the circuit can provide either the voltage-mode or current-mode filter without changing circuit topology. Additionally, each function response can be selected by suitably selecting input signals with digital method. Without any external resistors, the proposed circuit is very suitable to further develop into an integrated circuit. The PSPICE simulation results are depicted. The given results agree well with the theoretical anticipation. The maximum power consumption is approximately 1.81 mW at plusmn1.5 V supply voltages.