A 2-2 Discrete Time Cascaded ΣΔ Modulator With NTF Zero Using Interstage Feedback

Author

Sanchez-Renedo, Manuel ; Paton, Susana ; Hernandez, Luis

Author_Institution

Carlos III Univ., Madrid

fYear

2006

fDate

10-13 Dec. 2006

Firstpage

954

Lastpage

957

Abstract

A novel discrete time cascaded sigma-delta modulator topology is presented. The overall noise transfer function (NTF) may be modified by means of an additional error feedback in the analog circuitry. Mismatch properties do not depend on the additional feedback path, and therefore the signal to noise ratio (SNR) may be improved by proper location of NTF zeros. Moreover, one of the NTF zeros may be programmable by means of analog trimming while digital cancellation filters remains unaffected. A low oversampling ratio (OSR) 2-2 cascade sigma-delta modulator is presented as a design example.

Keywords

circuit feedback; digital filters; discrete time filters; sigma-delta modulation; 2-2 discrete time cascaded SigmaDelta modulator; NTF zero; analog trimming; digital cancellation filters; interstage feedback; noise transfer function; sigma-delta modulator topology; Bandwidth; Delta-sigma modulation; Digital filters; Feedback; Multi-stage noise shaping; Noise cancellation; Noise shaping; Quantization; Topology; Transfer functions;

fLanguage

English

Publisher

ieee

Conference_Titel

Electronics, Circuits and Systems, 2006. ICECS '06. 13th IEEE International Conference on

Conference_Location

Nice

Print_ISBN

1-4244-0394-4

Electronic_ISBN

1-4244-0395-2

Type

conf

DOI

10.1109/ICECS.2006.379948

Filename

4263526