Generation of continuous-time two integrator loop OTA filter structures

Author

Sanchez-Sinencio, Edgar ; Geiger, Randall L. ; Nevarez-Lozano, H.

Author_Institution

Dept. of Electr. Eng., Texas A&M Univ., College Station, TX, USA

Volume

35

Issue

8

fYear

1988

fDate

8/1/1988 12:00:00 AM

Firstpage

936

Lastpage

946

Abstract

Generation of two integrator loop filter structures using operational transconductance amplifiers (OTAs) and capacitors (TAC) is presented. A direct block diagram approach is used to generate the TAC filter structures. The basic filter building blocks consist of a lossless integrator, lossy integrators and the three types of summers. They are implemented using OTAs as the active components. The resulting TAC second-order filter structures, some previously reported and others new structures, are generated in an orderly way. It is shown that the selection of the best structure depends on the particular application or design specifications. The generated TAC biquadratic structures are only very suitable for monolithic filters since typically only OTAs and two capacitors are needed. A TAC filter structure homologous to the conventional KHN op amp filter structure is presented. Programmability of ω_p, Q_p and voltage gain is considered

Keywords

active filters; integrating circuits; network synthesis; operational amplifiers; OTA filter structures; active filters; biquadratic structures; continuous-time; lossless integrator; lossy integrators; monolithic filters; operational transconductance amplifiers; second-order filter; summers; two integrator loop; voltage gain programmability; Active filters; Adders; Capacitors; Circuits; Equations; Impedance; Operational amplifiers; Resistors; Transconductance; Voltage control;

fLanguage

English

Journal_Title

Circuits and Systems, IEEE Transactions on

Publisher

ieee

ISSN

0098-4094

Type

jour

DOI

10.1109/31.1840

Filename

1840