Voltage-Controlled Current-Mode Multifunction Filter Employing CFTAs and PCAs
Norbert Herencsar, Jaroslav Koton, Kamil Vrba and Ivo Lattenberg
This paper presents a novel voltage-controlled current-mode second-order multifunction frequency filter employing CFTAs (Current Follower Transconductance Amplifier) and PCAs (Programmable Current Amplifier). Possible internal bipolar structure of the CFTA+/- element and the realization of the PCA using current multiplier EL2082 and second generation current conveyor CCII+/- are presented. The proposed filter structure enables realizing the low- (LP), band- (BP), high-pass (HP) and the band-stop (BS) responses. The properties of the proposed filter were verified using PSPICE simulations.
Keywords: Active filter, Current-mode circuit, Current Follower Transconductance Amplifier (CFTA), Multifunctional filter, Programmable Current Amplifier (PCA).