Implication and evaluation techniques for proving fault equivalence

Efficient identification of fault equivalence is essential for the completeness and efficiency of diagnostic test pattern generation. In this paper we present new techniques to prove diagnostic fault equivalence. The techniques are based on implication of the faulty values, and functional evaluation at the dominator gate of the fault sites. The experimental results for all ISCAS85 circuits and full scan versions of ISCAS89 circuits show significant improvement compared to previously proposed techniques in both the number of equivalent pairs identified and the time to prove equivalence.