IEEE Transactions on Applied Superconductivity

Direct determination of the ultimate performance of the RSFQ digital devices and single flux quantum voltage amplifiers

E. Goldobin, Vladimir Golomidov, V. K. Kaplunenko, M. Khabipov, D.Yu. Khokhlov, Anna Kidiyarova-Shevchenko

Published Mar 1, 1993• 18 citations

Abstract

The fault-free switching of single-flux-quantum (SFQ) elements was studied by investigating SFQ pulse propagation in a ring Josephson transmission line closed with an SFQ inverter. A lifetime of more than a few hours was obtained that corresponds to at least 10/sup 15/ fault-free switching. The completely DC-powered rapid SFQ (RSFQ) sampler was used to directly measure the repetition rate stability of a Josephson generator loaded by a uniformly shunted transmission line. A stable repetition rate up to 7 GHz was obtained. The authors also report experimental results for two-stage serial and five-stage parallel quasi-digital amplifiers. The precision calculation of the input SFQ pulses is the main idea of these circuits.>

DOI: 10.1109/77.233970

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