Rapid Single Flux Quantum (RSFQ) logic is a promising technology to supersede Complementary metal-oxide-semiconductor (CMOS) logic in some specialized areas due to providing ultra-fast and energy-efficient circuits. To realize a large-scale integration design, electronic design automation (EDA) tools specialized for RSFQ logic are required due to the divergences in logic type, timing constraints, and circuit structure compared with CMOS logic. Logic synthesis is crucial in converting behavioral circuit description into circuit netlist, typically combining combinational and sequential circuit synthesis. For the RSFQ logic, the sequential circuit synthesis is challenging, especially for non-linear sequential blocks with feedback loops. Thus, this paper presents a sequential circuit synthesis algorithm based on finite state machine (FSM) decomposition, which ensures design functionality, lowers costs, and improves the RSFQ circuit performance. Additionally, we present the synthesis processes of the feedback logic and the 2-bit counter to demonstrate how the proposed algorithm operates, and ISCAS89 benchmark circuits reveal our method's ability to synthesize large-scale sequential circuits.
翻译:由于提供超快和节能电路,单一通量量快速逻辑是在某些专门领域取代辅助性金属-氧化半导体(CMOS)逻辑的一个大有希望的技术,因为提供超快和节能电路。为了实现大规模集成设计,需要专门用于RSFQ逻辑的电子设计自动化工具(EDA),因为与CMOS逻辑相比,逻辑类型、时间限制和电路结构存在差异。逻辑合成对于将行为电路描述转换成电路网列表至关重要,通常结合组合和顺序电路合成。对于RSFQ逻辑而言,连续电路合成具有挑战性,特别是对于非线性相继序列块和回路环。因此,本文介绍了基于有限状态机器分解定位的连续电路合成算法,确保设计功能、降低成本和改进RSFQ电路性。此外,我们介绍了反馈逻辑和二位反射线的合成过程,以显示拟议的算法是如何运作的,ISCRA89基准电路展示了我们的方法合成大型连续电路的能力。