IEEE Transactions on Applied Superconductivity

Bit-Error-Rate Measurements of RSFQ Shift Register Memories

T. Hikida, K. Fujiwara, Nobuyuki Yoshikawa, Akira Fujimaki, Hirotaka Terai, Shinichi Yorozu

Published Jun 1, 2007• 5 citations

Abstract

Error rates of rapid-single-flux-quantum (RSFQ) shift register memories were investigated using a high-speed error-rate measurement system in order to demonstrate their reliability and stability. We designed and implemented an 8 times 8-bit shift register memory using the CONNECT cell library and the SRL 2.5 kA/cm2Nb process. The total number of Josephson junctions including the test system is 4184, and the circuit area is 2.1 mm times 3.2 mm. We measured the error rates of every storage node by reading out the data 216times at the clock frequency of 16 GHz. The measured error rates were lower than 10-10with DC bias margin better than plusmn5%.

DOI: 10.1109/tasc.2007.898689

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