Current tunable current-mode TISO biquad filter consisting of two MCFTAs and minimum number of grounded capacitors

Abstract

This paper introduces a new current tunable current-mode biquad filter topology which is based on the active elements namely, modified current follower transconductance amplifiers (MCFTAs) and two grounded capacitors. It can realize all the five standard filtering responses such as band pass (BP), low pass (LP), high pass (HP), band reject (BR), and all pass (AP) at single high impedance current output through appropriate selection of three applied current inputs. So this circuit is three input single output (TISO) current-mode filter topology. The circuit offers an advantage of wide range of orthogonal electronic tunability of pole-frequency and quality factor and capable of realizing various filtering responses without using inverted and double current input signal. Moreover, the circuit also provides low active and passive sensitivities. Performance of the circuit is verified through P-SPICE simulation on ORCAD tool.