A single DAC CT sigma-delta modulator with Butterworth STF characteristic

Author

Brueckner, T. ; Zorny, C. ; Mathisy, W. ; Ortmanns, Maurits

Author_Institution

Inst. of Microelectron., Univ. of Ulm, Ulm, Germany

fYear

2011

fDate

7-10 Aug. 2011

Firstpage

1

Lastpage

4

Abstract

In this paper a continuous time Sigma-Delta modulator filter structure is proposed, which combines the known feed forward structure and an excess loop delay (ELD) compensation technique in order to realize an ELD compensated modulator with Butterworth signal transfer characteristic, which employs only one digital to analog converter (DAC) in the feedback path. A mapping strategy for the coefficient values is given and an exemplary modulator is evaluated through simulation. It is compared to a modulator with feed forward filter structure and an additional feedback path for ELD compensation. Furthermore an investigation on the sensitivity to coefficient variation is presented.

Keywords

Butterworth filters; compensation; continuous time filters; digital-analogue conversion; sigma-delta modulation; Butterworth STF characteristic; Butterworth signal transfer characteristic; ELD compensation technique; continuous time sigma-delta modulator filter structure; digital-to-analog converter; excess loop delay compensation technique; feed forward filter structure; mapping strategy; single-DAC CT sigma-delta modulator; CMOS integrated circuits; Hardware;

fLanguage

English

Publisher

ieee

Conference_Titel

Circuits and Systems (MWSCAS), 2011 IEEE 54th International Midwest Symposium on

Conference_Location

Seoul

ISSN

1548-3746

Print_ISBN

978-1-61284-856-3

Electronic_ISBN

1548-3746

Type

conf

DOI

10.1109/MWSCAS.2011.6026359

Filename

6026359