EXTENDED PHASE-MODE LOGIC-CIRCUITS WITH RESISTIVE GROUND CONTACT

We present an extended phase-mode logic (EPL) circuits which have resi stive ground contact. The phase-mode logic utilizes magnetic flux-tran sfer and is based on pulse propagation, i.e., it is one of single flux quantum systems. The proposed logic circuits of the EPL family can ha ve the same ground reference, contrary to the original phase-mode circ uits. Therefore, it is possible to couple different EPL elements on a single ground reference. Basic components of the EPL family (a phase-c onserving branch, a phase-distributing branch, and an INHIBIT gate con trolled by fluxon) are presented. The phase-distributing branch and th e INHIBIT gate have been fabricated using a Nb/AlOx/Nb Josephson-junct ion technology and tested. A fan-in operation of the phase-distributin g branch and the first full operation of the INHIBIT gate are successf ully demonstrated. As an example of the EPL logic circuits consisting of plural gates on a single ground reference, a simulation of a 2-bit full adder circuit is also presented.