A fully integrated 16-channel rsfq autocorrelator operating at 11 GHz

We present the results of low- and highspeed testing of a fully integrated all-digital one-bit RSFQ autocorrelator for short-millimeter and submillimeter wave spectrometry applications. The 16channel device, complete with a 16×9 array of binary counters, on-chip double-oversampling quantizer and on-chip clock was operational at clock speeds of up to 11 GHz. The total number of Josephson junctions in the design was 1672, while the estimated total power dissipation was less than 0.1 mW. For high-speed testing of the device we have developed a specialized 16channel room-temperature interface capable of realtime data acquisition at a 16 Mbps-per-channel output rate. Extensive high-speed on-chip testing of the autocorrelator has also been performed, both in analog and digital modes, in the latter mode with an additional on-chip clock controller. All chips were fabricated in HYPRES' standard 3.5-μm 10 μA/μm² Nbtrilayer process. We also present a new concept of a 128-channel autocorrelator system built on 8 independent identical chips with approximately 2,500 Josephson junctions per chip, i.e. within the reach of the present-day fabrication technology.