Superconductor Science and Technology

Reduction of power consumption of RSFQ circuits by inductance-load biasing

Nobuyuki Yoshikawa, Yuichi Kato

Published Nov 1, 1999• 80 citations

Abstract

We propose an inductance-load-biasing method in order to reduce power consumption of rapid single flux quantum (SFQ) logic circuits. The main idea arises from the fact that a current source can be made of a large inductor accompanied by a large flux. In our proposal, the current source is composed of a large inductor L b , a small resistor R b and a small voltage source V b . Computer simulations of inductance-load-biased Josephson transmission lines (JTLs) show that an SFQ pulse propagates correctly when L b is large enough even if R b is very small. In order to implement the inductance-load-biased JTL, we have made two different layouts: one uses a large bias inductance L b of a typical stripline structure on a ground plane which occupies a rather large area; the other uses L b in the shape of a coplanar stripline, which costs a smaller area.

DOI: 10.1088/0953-2048/12/11/367

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