Tools for the computer-aided design of multigigahertz superconducting digital circuits

The realization of large integrated circuits depends upon the application o f computer-aided design (CAD) tools, This paper summarizes the results of a survey of CAD tools targeting superconducting digital electronics. Five ca tegories of tools: circuit simulators, circuit optimizers, layout tools, in ductance estimators, and logic simulators are discussed in detail. Within e ach category, a comparison of several currently available CAD tools is pres ented, and a tool which has been adapted for use or developed at the Univer sity of Rochester is discussed in greater detail. In addition, tools for ti ming analysis as well as integrated design environments that permit the eff ective data interchange among various tools and support libraries of design models are discussed, Future tools for timing optimization, automated logi c synthesis, and automated layout synthesis are shown to be necessary for t he design of superconducting circuits at the very large scale of integratio n (VLSI) level of integration. Trends regarding changes in the requirements for effective CAD tools are discussed, and expected improvements to existi ng tools and features of new tools currently under development are presente d.