IEEE Transactions on Applied Superconductivity

Single Source SFQ Multiclock Generator Using Resistor–JTL Branches

Tejumadejesu Oluwadamilare, Shay Hacohen-Gourgy, Eby G. Friedman

Published Nov 7, 2025• 0 citations

Abstract

Systems requiring multiple clock frequencies are becoming more common in digital superconductive electronics. In rapid single flux quantum (RSFQ) circuits, precise frequencies are applied to different clock domains. A diverse variety of SFQ clock generators have been employed to produce a single frequency. A clock generator that uses a single voltage source to deliver multiple frequencies is presented here. The operating principle, performance, area, and power of the proposed SFQ multi-clock generator are described. Previously published clock generators are limited to a fixed frequency or varied by changing the bias DC voltage—a parameter not typically changedin situ. In the proposed approach, the clock frequency is tunable by the SFQ logic circuit. In addition, a globally asynchronous locally synchronous system is presented to exemplify the practical application of the proposed multi-clock generator

DOI: 10.1109/tasc.2025.3630889

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