Bipolar State-Variable Filter for High Frequencies

Author

Wolffenbuttel, R.F. ; van Kampen, R.P.

Author_Institution

Dept. of Electr. Eng., Delft Univ. of Technol., Delft, Netherlands

Volume

1

fYear

1990

fDate

19-21 Sept. 1990

Firstpage

181

Lastpage

184

Abstract

A time-continuous programmable State-Variable filter is presented that has been realised using bipolar OTA´s. A high input resistance and a good linearity is maintained irrespective of the programming of the transconductance using an OTA with a separated voltage-to-current input stage and a current-attenuation stage. A special common-mode loop is implemented to avoid the charging of the filter capacitors by an output bias current. Filters can be designed with resonance frequencies up to 40 MHz and Q factors ranging from 1 to 10.

Keywords

Q-factor; bipolar integrated circuits; capacitors; circuit resonance; operational amplifiers; programmable filters; Q factors; bipolar OTA; bipolar state-variable filter; current-attenuation stage; filter capacitors; input resistance; output bias current; resonance frequency; separated voltage-to-current input stage; special common-mode loop; time-continuous programmable state-variable filter; transconductance; Active filters; Attenuators; Band pass filters; Linearity; Operational amplifiers; Q factor; Resonance; Resonant frequency; Transconductance; Voltage;

fLanguage

English

Publisher

ieee

Conference_Titel

Solid-State Circuits Conference, 1990. ESSCIRC '90. Sixteenth European

Conference_Location

Grenoble

Print_ISBN

2-86332-087-4

Type

conf

Filename

5467750