FUNCTIONAL VERIFICATION OF POWER GATED DESIGNS BY COMPOSITIONAL REASONING

A novel and useful method of functional verification of power gated designs by compositional reasoning. The method of the present invention performs a sequential equivalence check between the power gated design and a version of itself in which power gating is disabled. A compositional approach is first used to look for conditional equivalence of each functional block of the circuit (and its corresponding functional block with power gating disabled) under a suitable set of assumptions, guaranteed by the neighboring functional blocks. Circular reasoning rules are then employed to compose the conditional equivalences proved on the individual functional blocks back into total equivalence on the whole circuit.