Electronically tunable versatile current-mode MISO universal filter including minimum component count circuits

An analog second order current-mode filter is described in this paper. The proposed filter uses only a single active building block, namely current following cascaded transconductance amplifier with two grounded capacitors which is attractive for monolithic chip implementation. The circuit has four inputs and single output currents. Five standard functions, namely low-pass, high-pass, band-pass, band-reject and all-pass functions, are given. The natural pole frequency and quality factor can be tuned electronically via the input bias current. The inverting-type input current signal is not required for realization of all-pass function. High output impedance is achieved which is convenient to cascade in current-mode circuit. The PSPICE simulation results are depicted. The given results agree well with the theoretical anticipation.