Asynchronous circuits and systems

Despite the recommendations of several Roadmaps published a few years ago, asynchronous circuits are only very recently becoming an industrial/commercial reality. The semiconductor industry is starting to give a serious consideration to the introduction of asynchronous technology into products and design flows. The paper introduces the design and applications of asynchronous circuits. Differences between synchronous and asynchronous circuits are first highlighted, and the main classes of asynchronous circuits introduced and compared. The main design methodologies available today are then briefly reviewed. Finally, it is shown that asynchronous logic may appear to be a key technology for the design of future telecommunication applications. The major potentials and properties of asynchronous circuits are described and illustrated with recently fabricated circuits and systems borrowed from both academic and industrial projects.