A Programmable Impedance Matching Circuit for Voiceband Modems

Author

Hershbarger, Russell A. ; Jia, Wenyan ; Tey, Kiam M. ; Fukahori, Kiyoshi ; Hurst, Paul J. ; Kapoor, Manprit

Author_Institution

Teridian Semicond., Mountain View

Volume

43

Issue

2

fYear

2008

Firstpage

468

Lastpage

476

Abstract

A line impedance-matching circuit for a voiceband modem is described. The circuit can be programmed to realize four different impedances. A switched-capacitor filter is used to generate the required transfer functions. The impedance-matching concept and circuits are described. Measured results are presented that show that the four impedances are realized with sufficient accuracy for voiceband modems. The circuit was fabricated in a standard 0.35-mum mixed-signal CMOS process.

Keywords

CMOS integrated circuits; impedance matching; mixed analogue-digital integrated circuits; modems; programmable circuits; switched capacitor filters; line impedance-matching circuit; mixed-signal CMOS process; programmable impedance matching circuit; size 0.35 mum; switched-capacitor filter; transfer function; voiceband modem; Analog-digital conversion; CMOS integrated circuits; CMOS process; Capacitors; Digital filters; Digital signal processing; Feeds; Impedance matching; Interpolation; Modems; Impedance matching; modem; switched-capacitor circuit;

fLanguage

English

Journal_Title

Solid-State Circuits, IEEE Journal of

Publisher

ieee

ISSN

0018-9200

Type

jour

DOI

10.1109/JSSC.2007.914298

Filename

4444564