Title
Variability-Aware Approximate Circuit Synthesis via Genetic Optimization
Abstract
One of the major barriers that CMOS devices face at nanometer scale is increasing parameter variation due to manufacturing imperfections. Process variations severely inhibit the reliable operation of circuits, as the operational frequency at the nominal process corner is insufficient to suppress timing violations across the entire variability spectrum. To avoid variability-induced timing errors, previous efforts impose pessimistic and performance-degrading timing guardbands atop the operating frequency. In this work, we employ approximate computing principles and propose a circuit-agnostic automated framework for generating variability-aware approximate circuits that eliminate process-induced timing guardbands. Variability effects are accurately portrayed with the creation of variation-aware standard cell libraries, fully compatible with standard EDA tools. The underlying transistors are fully calibrated against industrial measurements from Intel 14nm FinFET in which both electrical characteristics of transistors and variability effects are accurately captured. In this work, we explore the design space of approximate variability-aware designs to automatically generate circuits of reduced variability and increased performance without the need for timing guardbands. Experimental results show that by introducing negligible functional error of merely <inline-formula xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink"> <tex-math notation="LaTeX">$\boldsymbol {5.3 \times 10^{-3}}$ </tex-math></inline-formula> , our variability-aware approximate circuits can be reliably operated under process variations without sacrificing the application performance.
Year
DOI
Venue
2022
10.1109/TCSI.2022.3183858
IEEE Transactions on Circuits and Systems I: Regular Papers
Keywords
DocType
Volume
Approximate computing,process variation,logic synthesis,genetic algorithm
Journal
69
Issue
ISSN
Citations 
10
1549-8328
0
PageRank 
References 
Authors
0.34
20
6
Name
Order
Citations
PageRank
Konstantinos Balaskas100.68
Florian Klemme200.34
Georgios Zervakis300.34
Kostas Siozios416936.00
Hussam Amrouch525150.22
J. Henkel64471366.50