History, Progress and New Results in Synthetic Passive Element Design Employing CFTAs

Abstract

After the presentation of the Current Follower Transconductance Amplifier (CFTA) active element, it has found a numerous application possibilities while designing linear and non-linear analog function blocks. This paper gives a short review of the CFTA and mainly focuses on the synthetic floating and grounded passive element design, which can also be electronically controllable. Except the design of synthetic inductors, also possible realizations of floating and grounded capacitors and resistors are described, where the value of these passive elements can be adjusted by means of active elements' parameters. For the design of the corresponding circuit realizations, the Mason-Coates signal flow graph approach is used. The performance of some discussed synthetic elements is verified and evaluated by Spice simulations on simple analog frequency filters.After the presentation of the Current Follower Transconductance Amplifier (CFTA) active element, it has found a numerous application possibilities while designing linear and non-linear analog function blocks. This paper gives a short review of the CFTA and mainly focuses on the synthetic floating and grounded passive element design, which can also be electronically controllable. Except the design of synthetic inductors, also possible realizations of floating and grounded capacitors and resistors are described, where the value of these passive elements can be adjusted by means of active elements' parameters. For the design of the corresponding circuit realizations, the Mason-Coates signal flow graph approach is used. The performance of some discussed synthetic elements is verified and evaluated by Spice simulations on simple analog frequency filters.