Limitations on performance of Superconductor oversampling ADCs

Author

Semenov, Vasili K. ; Inamdar, Amol

Author_Institution

Dept. of Phys. & Astron., State Univ. of New York, Stony Brook, NY, USA

Volume

15

Issue

2

fYear

2005

fDate

6/1/2005 12:00:00 AM

Firstpage

435

Lastpage

438

Abstract

We discuss several general questions related to the development and optimization of superconductor oversampling modulators. We highlight the importance of specially engineered and parasitic components of the feedback loop. In particular, LR circuits operating as low-pass filters are capable of providing a noticeable SNR improvement and dramatically reducing the dynamic range requirements for used SFQ comparators. On the other hand, the feedback loop delay and time-jitter in timing circuits are able to spoil the potentially extremely high performance of superconductor oversampling ADCs. We also developed a simple formula describing time-jitter in superconductor circuits.

Keywords

analogue-digital conversion; comparators (circuits); low-pass filters; modulators; superconducting integrated circuits; timing circuits; timing jitter; LR circuits; RSFQ; SFQ comparators; SNR improvement; digital SQUID; dynamic range requirements; feedback loop delay; low-pass filters; parasitic components; superconducting devices; superconductor circuits; superconductor oversampling ADC; superconductor oversampling modulators; thermal noise; time-jitter; timing circuits; Delay; Dynamic range; Feedback loop; Frequency estimation; Integrated circuit noise; Josephson junctions; Low pass filters; Superconducting device noise; Superconducting filters; Superconducting integrated circuits; ADC; RSFQ; digital SQUID; influence of thermal noise; superconducting devices;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2005.849868

Filename

1439668