A novel Globally Asynchronous Locally Synchronous (GALS) technique applicable to datapath architectures is presented. It is based on a request-driven operation of locally synchronous blocks. Inactivity of the request line is detected with a special time-out circuitry. When time-out occurs, clocking of the locally synchronous block is handed over to a local ring oscillator. Based on this concept, a practical hardware implementation of an asynchronous wrapper is proposed. The simulation results presented demonstrate the potential and performance of the proposed GALS architecture.


Output Port Input Port Clock Signal Ring Oscillator Local Clock 
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Copyright information

© Springer-Verlag Berlin Heidelberg 2003

Authors and Affiliations

  • Miloš Krstić
    • 1
  • Eckhard Grass
    • 1
  1. 1.IHPFrankfurt (Oder)Germany

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