Definition
Equivalence checking is a portion of a larger discipline called formal verification. This technology uses mathematical modeling techniques to prove that two representations of design exhibit the same behavior. This approach should not be confused with functional verification, which uses exhaustive simulation to verify the correctness of a design.
Once a verified version of a design has been identified, equivalence checking can be used to determine if an alternate representation of the design behaves the same as the verified version. This technique does not use input vectors so it is more efficient.
Equivalence checking is useful to verify that a design’s function has not changed after an operation like synthesis, or after a functional ECO has been applied.