Wire Optimization and Delay Reduction for High-Performance on-Chip Interconnection in GALS Systems

  • Oh, Myeong-Hoon (SW & Contents Research Laboratory, ETRI and the Department of Computer Software, University of Science and Technology (UST)) ;
  • Kim, Young Woo (SW & Contents Research Laboratory, ETRI and the Department of Computer Software, University of Science and Technology (UST)) ;
  • Kim, Hag Young (SW & Contents Research Laboratory, ETRI) ;
  • Kim, Young-Kyun (SW & Contents Research Laboratory, ETRI) ;
  • Kim, Jin-Sung (Department of Electronic Engineering, Sun Moon University)
  • Received : 2016.08.11
  • Accepted : 2017.05.22
  • Published : 2017.08.01


To address the wire complexity problem in large-scale globally asynchronous, locally synchronous systems, a current-mode ternary encoding scheme was devised for a two-phase asynchronous protocol. However, for data transmission through a very long wire, few studies have been conducted on reducing the long propagation delay in current-mode circuits. Hence, this paper proposes a current steering logic (CSL) that is able to minimize the long delay for the devised current-mode ternary encoding scheme. The CSL creates pulse signals that charge or discharge the output signal in advance for a short period of time, and as a result, helps prevent a slack in the current signals. The encoder and decoder circuits employing the CSL are implemented using $0.25-{\mu}m$ CMOS technology. The results of an HSPICE simulation show that the normal and optimal mode operations of the CSL achieve a delay reduction of 11.8% and 28.1%, respectively, when compared to the original scheme for a 10-mm wire. They also reduce the power-delay product by 9.6% and 22.5%, respectively, at a data rate of 100 Mb/s for the same wire length.


Grant : Low-power and High-density Micro Server System Development for Cloud Infrastructure

Supported by : Institute for Information & communications Technology Promotion(IITP)


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