Method and apparatus for estimating elmore delays within circuit designs

摘要

A system for rapidly accurate Elmore delays is disclosed which uses circuit simulations with different circuit configurations to generate Elmore delay models. From data generated by the simulations, Elmore delays are represented as functions of a capacitance charge and device width for a variety of device configurations. Similarly, accurate capacitance models are determined for each device. To determine an Elmore delay for a discharge path, the appropriate models are applied to each device and summed together. Within a timing verifier, the present invention can rapidly determine critical paths which require additional consideration.