Preliminary results on the analog-to-digital converter based on RSFQ logic

The first laboratory prototype of a superconductor analog-to-digital converter (ADC) with on-chip fast digital signal processing has been designed and tested at internal clock frequencies up to 7 GHz. Estimated accuracy of the prototype is about 12 bit for 7 MHz signal bandwidth; at lower frequencies the dynamic range increases at least as fast as the reciprocal bandwidth. The single-chip (5/spl times/5 mm/sup 2/) device contains 1778 Josephson junctions and dissipates power at about 0.5 mW.