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Timing-aware power-optimal ordering of signals

Published: 03 October 2008 Publication History

Abstract

A computationally efficient technique for reducing interconnect active power in VLSI systems is presented. Power reduction is accomplished by simultaneous wire spacing and net ordering, such that cross-capacitances between wires are optimally shared. The existence of a unique power-optimal wire order within a bundle is proven, and a method to construct this order is derived. The optimal order of wires depends only on the activity factors of the underlying signals; hence, it can be performed prior to spacing optimization. By using this order of wires, optimality of the combined solution is guaranteed (as compared with any other ordering and spacing of the wires). Timing-aware power optimization is enabled by simultaneously considering timing criticality weights and activity factors for the signals. The proposed algorithm has been applied to various interconnect layouts, including wire bundles from high-end microprocessor circuits in 65 nm technology. Interconnect power reduction of 17% on average has been observed in such bundles.

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cover image ACM Transactions on Design Automation of Electronic Systems
ACM Transactions on Design Automation of Electronic Systems  Volume 13, Issue 4
September 2008
328 pages
ISSN:1084-4309
EISSN:1557-7309
DOI:10.1145/1391962
Issue’s Table of Contents
Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected]

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Publication History

Published: 03 October 2008
Accepted: 01 June 2008
Revised: 01 June 2008
Received: 01 June 2007
Published in TODAES Volume 13, Issue 4

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Author Tags

  1. Wire ordering
  2. interconnect optimization
  3. power optimization
  4. wire spacing

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