First-order allpass sections-based high-input low output impedance voltage-mode universal filter using FDCCIIs

A new voltage-mode second order universal active-RC filter with multiple inputs and single output using fully differential current conveyors (FDCCII) is presented. This filter is based on first order allpass sections which use minimum passive components. Proposed voltage-mode filter can be easily cascaded to get higher order filter characteristics because of having high-input and low-output impedances. The circuit simultaneously provides the basic filter characteristics, namely high-pass (HP), band-pass (BP), low-pass (LP), all-pass (AP) and notch (NO) without needing any additional inverting active element. It has low sensitivity to the passive components. SPICE simulation results are given to verify theoretical analysis.