Versatile active biquad using FTFNs

A universal active biquad using the four-terminal floating nullors (FTFNs) is presented. The propsed circuit uses two FTFNs, three capacitors and two resistors. The proposed circuit has three input voltages and can simultaneously provide a high-impedance output current and/or an output voltage. Without changing the circuit topology, the output voltage can realise lowpass. highpass, bandpass, notch and all pass transfer functions and the output current can realise bandpass and highpass transfer functions The proposed circuit enjoys low active and passive sensitivities and independent control of the parameters w_o and w_o/Q_o.