Room Temperature Interface for RSFQ Digital Signal Processor

Journal article, 2007

This paper describes a cryogenic Multi-Chip Module (MCM) probe for testing of a superconducting hybrid Digital Signal Processor (DSP) capable of 24 giga multiply accumulate operations per second. The probe has 39 data channels with 4 GHz bandwidth, a 30 GHz high speed clock input line, and 48 biasing lines. The MCM interface board features 164 spring finger contacts for a 30 mm x 30 mm MCM. The probe has low heatload (0.23 W) and provides good magnetic shielding with residual field equal to 250 Flux quanta over a 5 mm x 5 mm area. The measured time skew between 20 of the 1200 mm data coaxial lines is about 70 ps. The probe allows synchronous data word transmission at 2 Gbps.