Studies on Logic Design Methods Adaptable to CAD DB

随着逻辑电路变得越来越庞大和复杂，设计数据的重用和逻辑电路的设计自动化变得非常重要。虽然CAD数据库是实现设计数据重用的必不可少的技术，但现有的设计方法和数据库技术很难实现集成。为此，我们研究并改进了适合数据库的逻辑电路设计方法，实现了CAD数据库。本研究的主题包括转换方法的改进、逻辑电路设计方法的开发、逻辑电路重用技术的开发和逻辑电路功耗节约技术的开发。1998年，我们开发了允许功能超集(SSPF)，扩展了转换方法使用的兼容允许功能集(CSPF)，增加了逻辑电路转换的自由度。我们还提出了…的PSPFD(基于优先级的SPFD进一步推广了表示FPGA电路逻辑自由度的SPFD概念，使电路面积减少了40%。提出了一种新的基于三态CMOS的低功耗逻辑电路设计算法，并实现了考虑功耗的功能分配。1999年，我们提出了两种方法：一种是将模拟退火法和元启发式方法应用于转换法，另一种是基于转换法中允许函数概念的逻辑优化方法，以期实现比现有的CMOS逻辑更低功耗的电路。2000年，我们改进了传输管逻辑电路的优化方法。我们在一本35年前出版的逻辑电路书中发现了错误，这本书收集了用改进的方法手工计算的最小电路。其次，一种优化方法的发展取得了进展。我们已经将这种方法应用于前一年为减少逻辑门中的晶体管数量而开发的通路晶体管逻辑。我们还引入并应用了转换方法来减少逻辑门的数量。将CMOS逻辑优化方法与传感法相结合，发展了一种更有效的逻辑电路优化方法。较少

Reuse of design data and design automation of logic circuits becomes important because logic circuits become to have large and complex structure. Though the CAD database is an indispensable technology to realize reuse of design data, it is difficult to integrate existing design methods and database technology as it is. Thus we have studied and improved design methods of logic circuits suitable for databases, which realize the CAD database. The themes of this research includes an improvement of the transduction method, development of a method for FPGA logic circuit design, development of a reuse technique of logic circuits, and development of a technique for saving power consumption of logic circuits.In 1998, we have developed SSPFs (Super Set of Permissible Functions) that extend CSPFs (Compatible Sets of Permissible Functions) used by the transduction method and increased the degree of freedom in transformation of logic circuits. We also have proposed PSPFDs (Priority based SPFDs) tha … More t generalize the notion of SPFDs representing the logical degree of freedom of FPGA circuits and achieved a 40% reduction in the area of circuits. We have proposed a new algorithm for logic circuit design with saving power consumption that uses 3-state CMOS and realized the function assignment considering saving power consumption.In 1999, we have developed two methods : a method that applies simulated annealing, one of metaheuristics, to the transduction method, and a method of logic optimization based on the notion of PF (Permissible Function) used by the transduction method for a pass transistor logic that is expected to realize more low power consumption circuits than existing CMOS logic.In 2000, first, we have improved the optimization method for pass transistor logic circuits. we have found errors in a book of logic circuits, published more than 35 years ago, that collects minimal circuits calculated by hand by the improved method. Secondly, the development of a optimization method of CMOS logic have progressed. We have applied the method to the pass transistor logic that developed the preceding year for decreasing the number of transistors in logic gates. We also have introduced and applied the transduction method to reduce the number of logic gates. More effective optimization method of logic circuits have been developed by integrating the CMOS logic optimization method and the transduction method. Less