부산대학교 도서관

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 ${\rm kA/cm}^{2}$ Nb 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 $2^{16}$ times at the clock frequency of 16 GHz. The measured error rates were lower than $10^{-10}$ with DC bias margin better than $\pm$5%.