As feature sizes scale toward atomic limits, parameter variation continues to
increase, leading to increased margins in both delay and energy. The
possibility of very slow devices on critical paths forces designers to increase
transistor sizes, reduce clock speed and operate at higher voltages than
desired in order to meet timing. With post-fabrication configurability, FPGAs
have the opportunity to use slow devices on non-critical paths while selecting
fast devices for critical paths. To understand the potential benefit we might
gain from component-specific mapping, we quantify the margins associated with
parameter variation in FPGAs over a wide range of predictive technologies
(45nm--12nm) and gate sizes and show how these margins can be significantly
reduced by delay-aware, component-specific routing. For the Toronto 20
benchmark set, we show that component-specific routing can eliminate delay
margins induced by variation and reduce energy for energy minimal designs by
1.42--1.98x. We further show that these benefits increase as technology
scales.
Copyright 2012 ACM,
Inc.
This is the author's version of the work. It is posted here by permission
of ACM for your personal use. Not for redistribution. The definitive
version was published in the Proceedings of the
International Symposium on Field-Programmable Gate Arrays,
(FPGA2012, February 22--24 2012).
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