The Research On The Asynchronous Circuits Design Method

The asynchronous design and synchronous design are the two basic methods in implementing the digit system. The main difference is how implement the unisonous operation of the logic hardware system: the distributed interstage acknowledge guarantees the coordination in asynchronous system and the global clock signal guarantees the coordination in synchronous system.The fact is that the SoC system needs the asynchronous technology in nanometer era. The cost of synchronous control system is very huge in nanometer scale. And at the same time, modular design, power indicator, etc. appeal to the asynchronous technology. Then, the asynchronous digital circuits are developed. The asynchronous circuits have the particular advantages in speed, power, noise, modularity and so on. However, the asynchronous design is the renascent technology, and still exists a lot of problems. This paper introduces the main design principles, methods, and building blocks for asynchronous VLSI systems and lays a foundation for the design of the asynchronous VLSI system.All work in this paper are: research the handshaking protocol, signaling protocol, data encoding protocol and the various implementation styles of handshaking protocol; analysis the delay issue in asynchronous circuits, set up the corresponding delay model and present the classification of the asynchronous; research the main design principles, methods, and building blocks for asynchronous VLSI systems, with an emphasis on communication and synchronization; research the high-level language in asynchronous design: CHP( Communicating Hardware Processes), HSE(Handshaking Expansion), PRS(Production Rule Set), and descript the design process by using the language; at last, implement a full adder as the example.