Single CFTA-based dual-mode biquadratic filter

A scheme consisting of only one current follower transconductance amplifier (CFTA) and four passive components is introduced for realizing the novel dual-mode universal biquadratic filter. The introduced filter can perform either in voltage-mode or current-mode, and can realize the highpass, bandpass and lowpass filter responses simultaneously without needing any element matching constraints. The natural angular frequency (mo) and the quality factor (Q) of the filter can be tuned electronically by the transconductance gain of the CFTA. Computer simulations are used to confirm the workability of the proposed circuit.