Error rate test of large-scale SFQ digital circuit systems

Author

Fujiwara, Kan ; Nakajima, Naoki ; Nishigai, Takanobu ; Ito, Maki ; Yoshikawa, Nobuyuki ; Fujimaki, Akira ; Terai, Hirotaka ; Yorozu, Sinichi

Author_Institution

Dept. of Electr. & Comput. Eng., Yokohama Nat. Univ., Japan

Volume

15

Issue

2

fYear

2005

fDate

6/1/2005 12:00:00 AM

Firstpage

427

Lastpage

430

Abstract

We have been developing large-scale SFQ digital circuit systems and have shown the successful demonstration of our prototype SFQ microprocessors and memories. Their circuit scale is now over several thousands of junctions. One question arising in such large SFQ circuits is whether their error rate is low enough for digital applications. In this study, we have examined the error rate of circuit components of our microprocessor. An error rate test system for a program counter (PC) of the CORE1 microprocessor was made using Nb 2.5 kA/cm² process. The system is composed of a clock generator, a comparator and a 16-bit PC under test. It was found from the experiment that the system error rate of the 16-bit PC is lower than 10^-8, which corresponds to a bit-error-rate better than 10^-12. We have also evaluated a timing jitter of the clock generator and an effective temperature of the PC based on the experimental results.

Keywords

error statistics; large scale integration; microprocessor chips; superconducting memory circuits; superconducting processor circuits; timing jitter; 16 bit; 16-bit PC; CORE1 microprocessor; bit-error-rate; circuit components; circuit scale; clock generator; comparator; error rate test system; large-scale SFQ digital circuit systems; program counter; prototype SFQ microprocessors memory; superconductive circuits; timing jitter; Circuit testing; Clocks; Counting circuits; Digital circuits; Error analysis; Large-scale systems; Microprocessors; Niobium; Prototypes; System testing; Bit error rate; SFQ; digital circuit; jitter; superconductive circuits;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/TASC.2005.849866

Filename

1439666