HIGH IMPEDANCE VOLTAGE-MODE MULTIFUNCTION FILTERS IMPLEMENTED BY FTFNs AND OP-AMP

This paper presents a voltage-mode multifunction filter based on and employing two four-terminal floating nullors (FTFNs) and a single operational amplifier (OP-AMP). The high-input impedance voltage-mode configuration can simultaneously realize lowpass (LP), highpass (HP) and bandpass (BP) filtering functions from the same configuration. The circuit employs two grounded capacitors which suits contemporary IC design techniques. High output impedances of the proposed multifunction filter enable the circuits to be cascaded without requiring any impedance matching device. Passive sensitivity figures are low. The theoretical results are confirmed by PSPICE simulations.