Superconductor Science and Technology

Design and experimentation of BSFQ logic devices

T. Hosoki, Hiroki Kodaka, M Kitagawa, Yoji Okabe

Published Nov 1, 1999• 3 citations

Abstract

Rapid single flux quantum (RSFQ) logic needs synchronous pulses for each gate, so the clock-wiring problem is more serious when designing larger scale circuits with this logic. So we have proposed a new SFQ logic which follows Boolean algebra perfectly by using set and reset pulses. With this logic, the level information of current input is transmitted with these pulses generated by level-to-pulse converters, and each gate calculates logic using its phase level made by these pulses. Therefore, our logic needs no clock in each gate. We called this logic `Boolean SFQ (BSFQ) logic'. In this paper, we report design and experimentation for an AND gate with inverting input based on BSFQ logic. The experimental results for OR and XOR gates are also reported.

DOI: 10.1088/0953-2048/12/11/324

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