A 500-nA sixth-order bandpass SC filter

Author

Castello, Rinaldo ; Grassi, Alberto G. ; Donati, Stefano

Author_Institution

Dept. of Electron., Pavia Univ., Italy

Volume

25

Issue

3

fYear

1990

fDate

6/1/1990 12:00:00 AM

Firstpage

669

Lastpage

676

Abstract

A sixth-order bandpass switched-capacitor (SC) filter that requires only 500 nA of total supply current has been designed and fabricated in a 2-μm CMOS technology. The filter is part of an implantable device powered by a ±1.2-V battery; it can drive up to 30 pF of capacitive load and uses a 2-kHz sampling frequency. A substantial reduction in the power consumption has been achieved by using a novel amplifier time-sharing technique that allows the realization of an arbitrary number of biquadratic cells with only two amplifiers. Further power saving was obtained with the use of positive feedback in the amplifier input stage to enhance its transconductance. The prototype chip requires an area of 2200 mils²

Keywords

CMOS integrated circuits; active filters; band-pass filters; switched capacitor filters; 2 kHz; 2 micron; 500 nA; CMOS technology; amplifier input stage; amplifier time-sharing technique; biquadratic cells; capacitive load; implantable device; positive feedback; power consumption; sampling frequency; sixth-order bandpass SC filter; total supply current; transconductance; Band pass filters; Batteries; CMOS technology; Current supplies; Energy consumption; Feedback; Frequency; Power amplifiers; Sampling methods; Time sharing computer systems;

fLanguage

English

Journal_Title

Solid-State Circuits, IEEE Journal of

Publisher

ieee

ISSN

0018-9200

Type

jour

DOI

10.1109/4.102659

Filename

102659