Highly selective `analog´ filters using ΔΣ based IIR filtering

Author

Johns, D.A. ; Lewis, D.M. ; Cherepacha, D.

Author_Institution

Dept. of Electr. Eng., Toronto Univ., Ont., Canada

fYear

1993

fDate

3-6 May 1993

Firstpage

1302

Abstract

Design equations and experimental results for a second-order delta-sigma (Σ-Δ) based infinite impulse response (IIR) filter are presented. Although input and output signals are analog, filtering is performed directly on an oversampled Δ-Σ modulated signal, thus eliminating the need for any decimation or interpolation filters. Circuit complexity consists of only a single Δ-Σ analog-digital (A/D) modulator, approximately ten 26-b adders, a 1-b digital-analog converter (D/A) and a low-pass filter. It is shown experimentally that such a filtering technique can realize filter pole-Q´s of at least 2600 in the audio frequency range

Keywords

IIR filters; Q-factor; sigma-delta modulation; IIR filtering; adders; audio frequency range; delta-sigma based filter; digital-analog converter; highly selective filters; infinite impulse response; low-pass filter; oversampled Δ-Σ modulated signal; Adders; Analog-digital conversion; Complexity theory; Delta modulation; Digital modulation; Equations; Filtering; IIR filters; Interpolation; Low pass filters;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems, 1993., ISCAS '93, 1993 IEEE International Symposium on

Conference_Location

Chicago, IL

Print_ISBN

0-7803-1281-3

Type

conf

DOI

10.1109/ISCAS.1993.393969

Filename

393969