System and method for correlated process pessimism removal for static timing analysis

A system for performing static timing analysis of a digital system in the presence of a plurality of global sources of delay variation comprising:

• a) means for selecting, for at least one timing test, at least one pair of an early path and a late path leading to said timing test;
• b) means for identifying at least one global parameter which the delays of said early and late paths depend on, and mean for identifying parameters in which delay functions are separable;
• c) means for determining for at least one of said global parameters at least one consistent value assignment and means for setting dependently each of said parameters in which delay functions are separable to value that results in a worst slack value at said timing test;
• and
• d) means for computing for each said consistent assignment a slack value for said path pair.

A program storage device readable by a machine, tangibly, embodying a program of instructions executable by the machine to perform method steps for performing static timing analysis of a digital system in the presence of a plurality of global sources of delay variation, said method steps comprising:

• a) selecting, for at least one timing test, at least one pair of an early path and a late path leading to said timing test;
• b) identifying at least one global parameter which the delays of said early and late paths depend on, and identifying parameters which delay functions are separable;
• c) determining for at least one of said global parameters at least one consistent value assignment, and setting independently each of said parameters in which delay functions are separable to a value that results in a worst slack value at timing test
• d) computing for each said consistent assignment a slack value for said path pair.