Josephson output interfaces for RSFQ circuits

High bandwidth Josephson circuits were developed for interfacing the rapid single flux quantum (RSFQ) circuits' output to room temperature electronics. The RSFQ signal levels were amplified to voltage outputs in the 2-4 mV range using asynchronous direct current powered voltage driver circuits which were analyzed and tested for data rates of up to 8 Gb/s. Circuits integrated with drivers were successfully tested at low speed while shift registers integrated with voltage driver circuits were demonstrated at high-speed.