CLASIFICATION AND GENERATION OF Gm-C BAND-PASS FILTERS

Abstract

The programmable transconductance amplifier is a useful building block for continuous-time analog signal processing. Transconductors with capacitors (Gm-C) form an optimum and useful set of generating elements and circuits. These circuits have the advantages of tunability, simplicity and ability to operate at very high frequencies. The main objective of the thesis is to present a review of Gm-C elements and filters, as well as investigating the generation of high-performance Gm-C band-pass filters.

The first part of the thesis presents a review of Gm-C basic elements and sections including impedance realizations, amplifiers and first order filters. Then, different Gm-C filters generation methods are reviewed. A classification of second-order Gm-C band-pass filters is given based on their matrix representations. A comparison among all these filters is presented including PSpice simulations.

A new Op-amp-RC to Gm-C transformation method is introduced. The method is used to obtain high-performance Gm-C filters from well-known Op-amp-RC ones.

Finally, voltage-mode to current-mode transformation methods are presented and used to obtain current-mode Gm-C filters from their voltage-mode counterparts.