Input and output interfaces between RSFQ and semiconductor circuits

Superconducting converters between RSFQ subsystems in the return-to-zero (R Z) mode and semiconductor electronics in the non-return-to-zero (NRZ) mode are conceived, simulated (SPICE, CADENCE) and optimized (ABAK) for data tra nsmission at 10 GHz clock frequency and low power dissipation. An error cor rection scheme with a majority gate is used. RZ-to-NRZ converters with only 21 Josephson junctions are implemented with the 1 kA/cm(2) Niobium technol ogy in Karlsruhe and tested successfully at 4.2 K and 500 MHz. Improvements in fabrication and instrumentation will enable measurements at microwave c lock frequencies. (C) 1999 Elsevier Science B.V. All rights reserved.