Novel Solution of Notch/All-pass Filter with Special Electronic Adjusting of Attenuation in the Stop Band

Abstract

The notch/all-pass filter with two electronically adjustable three-port current conveyors of the second generation (CCIIs) or one conveyor and one voltage buffer employing only four passive elements is presented in this paper. Used active elements allow the control of current transfer via DC control voltage. Therefore an adjusting of the attenuation in the stop band of the notch filter is possible. The transfer function and major parasitic influences of real active parts are discussed. The verification includes PSpice simulation with professional macromodels and measurement with available current conveyors in frequency domain. Ill. 7, bibl. 40 (in English; abstracts in English and Lithuanian).

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