Design and demonstration of fundamental logic circuits based on a single-flux-quantum gate with a resettable latch

Author

Takeuchi, Nobuo ; Akahori, A. ; Mori, N. ; Suzuki, Y. ; Furuta, F. ; Fujimaki, A. ; Hayakawa, H.

Author_Institution

Dept. of Quantum Eng., Nagoya Univ., Japan

Volume

11

Issue

1

fYear

2001

fDate

3/1/2001 12:00:00 AM

Firstpage

966

Lastpage

969

Abstract

We have confirmed the importance of the tolerance design for obtaining correct operation in larger-scale Single Flux Quantum (SFQ) logic circuit. Experimental results show that the bias margin of SFQ/dc converter is considerably enhanced by employing tolerance design. The primitives of Single-Flux-Quantum-logic with Ressettable Latch (SFQ-RL) are designed to have high tolerance. As a result, relatively complex circuits based on SFQ-RL including 4-bit Shift Register, 3-Input Majority circuits, binary counter operate correctly with sufficient bias margins. These circuits are fabricated in NEC´s standard process using 2.5 kA/cm² Nb/AlOx/Nb junction technology

Keywords

counting circuits; flip-flops; logic design; logic gates; majority logic; shift registers; superconducting logic circuits; tolerance analysis; Nb-AlO-Nb; Nb/AlOx/Nb junction technology; SFQ/DC converter; binary counter; logic gate; majority circuit; optimization; resettable latch; shift register; single flux quantum logic circuit; tolerance design; Counting circuits; Critical current; DC-DC power converters; Energy consumption; Large-scale systems; Latches; Logic circuits; Logic design; Niobium; Numerical simulation;

fLanguage

English

Journal_Title

Applied Superconductivity, IEEE Transactions on

Publisher

ieee

ISSN

1051-8223

Type

jour

DOI

10.1109/77.919509

Filename

919509