Formal Methods in System Design

, Volume 28, Issue 2, pp 171–186 | Cite as

A predictive synchronizer for periodic clock domains

  • Uri Frank
  • Tsachy Kapshitz
  • Ran Ginosar


An adaptive predictive clock synchronizer for systems on chip incorporating multiple clock domains is presented. The synchronizer takes advantage of the periodic nature of clocks in order to predict potential conflicts in advance, and to conditionally employ an input sampling delay to avoid such conflicts. The result is conflict-free synchronization with maximal throughput and minimal latency. The adaptive predictive synchronizer adjusts automatically to a wide range of clock frequencies, regardless of whether the transmitter is faster or slower than the receiver. The synchronizer also avoids sampling duplicate data or missing any input. A novel method is presented for formal treatment of synchronizers and metastability. Correct operation of the synchronizer is formally proven and verified.


Clock Synchronization Predictive Synchronizer Systems on Chip (SoC) Formal Verification Multiple Clock Domains (MCD) Metastability 


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Copyright information

© Springer Science + Business Media, LLC 2006

Authors and Affiliations

  1. 1.VLSI Systems Research CenterTechnion—Israel Institute of TechnologyHaifaIsrael

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