An implicit path-delay fault diagnosis methodology

The first nonenumerative framework for diagnosing path delay faults (PDFs) using zero suppressed binary decision diagrams is introduced. We show that fault-free PDFs with certain validated nonrobust test may be used together with fault-free robustly tested faults to eliminate faults from the set of suspected faults. All operations are implemented by an implicit diagnosis tool based on the zero-suppressed binary decision diagram. The proposed method is space and time nonenumerative as opposed to existing methods which are space and time enumerative. Experimental results on the ISCAS´85 benchmarks show that the proposed technique is on average three times more efficient than the existing techniques.