Leakage minimization of nano-scale circuits in the presence of systematic and random variations

ABSTRACT

This paper presents a novel gate sizing methodology to minimize the leakage power in the presence of process variations. The leakage and delay are modeled as posynomials functions to formulate a geometric programming problem. The existing statistical leakage model of [18] is extended to include the variations in gate sizes as well as systematic variations. We propose techniques to efficiently evaluate constraints on the α-percentile of the path delays without enumerating the paths in the circuit. The complexity of evaluating the objectivefunction is O(|N|²) and that of evaluating the delay constraints is O(|N| + |E|) for a circuit with |N| gates and |E| wires. The optimization problem is then solved using a convex optimization algorithm that gives an exact solution.

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.6 LOGIC DESIGN
      B.6.3 Design Aids
          Subjects: Optimization

General Terms:
Algorithms, Design, Performance

Keywords:
geometric programming, leakage, optimization, statistical