A novel global self-timing methodology for BSFQ circuits

Recently we have proposed Boolean single-flux-quantum (BSFQ) circuits, which like CMOS circuits directly support Boolean primitives, and do not require local synchronization for their elementary cells as well as for their combinational cells. However, only the cell-level timing description of the BSFQ circuits was considered, which did not specify their global timing strategy in a system-level design. In this paper, we present a novel global self-timing methodology, dual encoding hierarchical pipelining (DEHP), for the locally asynchronous BSFQ circuits. In circuit implementation, a nonvolatile memory cell named ND-DFF and a volatile memory cell named D-DFF have been designed.