NBTI tolerance and leakage reduction using gate sizing

Abstract

Leakage power is a major design constraint in deep submicron technology and below. Meanwhile, transistor degradation due to Negative Bias Temperature Instability (NBTI) has emerged as one of the main reliability concerns in nanoscale technology. Gate sizing is a widely used technique to reduce circuit leakage, and this approach has recently attracted much attention with regard to improving circuits to tolerate NBTI. However, these studies only consider timing and area constraints, and many other important issues, such as slew and max-load, are missing. In this article, we present an efficient gate sizing framework that can reduce leakage and improve circuit reliability under timing constraints. Our algorithms consider slack, slew and max-load constraints. The benchmarks are those from ISPD 2012, which feature industrial design properties, including discrete cell sizes, nonconvex cell timing models, slew dependencies and constraints, as well as large design sizes. The experimental results obtained from ISPD 2012 benchmark circuits demonstrate that our approach can meet all the constraints and tolerated NBTI degradation with a power savings of 6.54% as compared with the traditional method.