Electronically tunable fractional-order low-pass filter with current followers

Proposal of a fractional (1+α)-order low-pass filter is presented in this paper. The proposed filter operates in the current-mode and it is designed using multi-output current followers (MO-CFs) and adjustable current amplifiers (ACAs). The filter possesses ability to electronically control its order and also the pole frequency. Verification of actual function of the filter is supported by the simulation results. The simulations were performed using Pspice simulator. The simulation results for three different values of its order and also three different values of pole frequency are illustrated and compared in this contribution.

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