Asynchronous circuits: an increasingly practical design solution

While ultra-deep-submicron design presents increasingly difficult challenges for standard synchronous design practices, recent research in asynchronous design techniques is making asynchronous circuits an increasingly practical alternative. These challenges include the increasing pressure for low-power, the growing challenge of predicting increasing impact of wire load and delay, and the performance penalty associated with supporting communication between different clock domains. This paper reviews the different solutions to these problems that the spectrum of existing asynchronous design techniques support. It focuses on techniques for fine-grain two-dimensional pipelining that yield ultra-high-speed at nominal power supplies and very low-energy at reduced power supplies.