Impact of OTA nonlinearities on the performance of continuous-time OTA-C bandpass filters

Author

Hiser, Douglas L. ; Geiger, Randall L.

Author_Institution

Inst. Microelectron. Products, San Jose, CA, USA

fYear

1990

fDate

1-3 May 1990

Firstpage

1167

Abstract

A new technique for predicting actual large-signal frequency responses, including jump resonance, in high-Q bandpass filters constructed from OTAs (operational transconductance amplifiers) and linear capacitors is presented. These predictions are a function of the nonlinearities of the OTAs and the Q enhancement of the filter. This approach offers significant advantages over other published techniques: a closed-form expression is obtained which is used to estimate the sensitivity of the nonideal filter parameters to signal amplitude, OTA distortion and Q enhancement, and which offers valuable insight into the nonideal operation of the filter. A representative filter structure is discussed. It shows close agreement between measurement and predicted responses in the presence of both Q enhancement and QTA distortions

Keywords

Q-factor; active filters; band-pass filters; frequency response; linear network analysis; lumped parameter networks; operational amplifiers; sensitivity analysis; OTA distortion; OTA nonlinearities; OTA-C bandpass filters; Q enhancement; continuous-time; high-Q filters; jump resonance; large-signal frequency responses; linear capacitors; nonideal filter parameters; nonideal operation; operational transconductance amplifiers; sensitivity; signal amplitude; Amplitude estimation; Band pass filters; Capacitors; Closed-form solution; Distortion measurement; Frequency; Operational amplifiers; Q measurement; Resonance; Transconductance;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems, 1990., IEEE International Symposium on

Conference_Location

New Orleans, LA

Type

conf

DOI

10.1109/ISCAS.1990.112329

Filename

112329