Globally Asynchronous Locally Synchronous Design Methodology

GALS(Globally Asynchronous Locally Synchronous) method well with the design of synchronous and asynchronous design method, has the advantage, especially in resolving the issue of time domain and update the reusability of modules such as in a unique position. Its design thinking is that the various functional modules are designed in synchronized manner. Then various synchronous modules are wrapt by synchronous-asynchronous conversion interface, and each module communicates asynchronously.In this thesis, a wide range of study is made in asynchronous circuit design principles, GALS system principles, methods and module design etc which lay the foundation for GALS design.The thesis focus on the work: a variety of C-Element (two-input C element, three-input C element, set-C element and reset-C element) circuits are introduced.The working principles of relevant circuits are analyzed.The models of transistor level are realized and simulated. The layout of three-input C element is presented. Also, several CMOS implementations of set-C element and reset-C element are proposed. A better implementation is concluded from the curves of energy consumption, rising delay and falling delay. GALS asynchronous wrapper circuit is designed, including synchronous-asynchronous communication ports and stretchable clock controller. With about 900 transistors, a point to point GALS system is successfully implemented. All simulation of this thesis is based on the 0.25μm typical CMOS technique.