Timing analysis in presence of supply voltage and temperature variations

ABSTRACT

In the nanometer era, the physical verification of CMOS digital circuit becomes a complex task. Designers must account of numerous new factors that impose a drastic change in validation and physical verification methods. One of these major changes in timing verification to handle process variation lies in the progressive development of statistical static timing engines. However the statistical approach cannot capture accurately the deterministic variations of both the voltage and temperature variations. Therefore, we define a novel method, based on non-linear derating coefficients, to account of these environmental variations. Based on temperature and voltage drop CAD tool reports, this method allows computing the delay of logical paths considering the operating conditions of each cell.

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INDEX TERMS

Primary Classification:
  B. Hardware
  B.7 INTEGRATED CIRCUITS
      B.7.2 Design Aids

General Terms:
Performance, Verification