Synthesizing Asynchronous Circuits: Practice and Experience

  • Al Davis
Part of the Workshops in Computing book series (WORKSHOPS COMP.)


Asynchronous circuit design has been a topic of study for over 40 years. Only recently has this study turned to the practical issues of building useful CAD tool support that approaches the level of functionality available in synchronous VLSI CAD systems. The existence of these asynchronous CAD systems enables today’s designers to construct asynchronous VLSI devices of significant size and scope. This chapter provides a reasonably detailed description of the process of developing a set of VLSI CAD tools which permit correct controller circuits to be synthesized from finite state machine style specifications. The tools were developed in two stages. The first stage resulted in a set of tools called MEAT, which were used to implement a 300,000 transistor multiprocessor routing chip called the Post Office. This Post Office experience provided the motivation for the second stage which resulted in the STETSON tool set which is integrated with the Mentor VLSI tool suite and was used to synthesize a low-power infrared transceiver chip called ABCS. The chapter presents a somewhat chronological view of the development of the CAD methods and provides examples of how well these methods worked in a practical design setting.


State Machine Flow Table Design Style Logic Hazard Asynchronous Circuit 
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Copyright information

© Springer-Verlag London 1995

Authors and Affiliations

  • Al Davis
    • 1
  1. 1.Department of Computer ScienceUniversity of UtahSalt Lake CityUSA

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