Exact path delay grading with fundamental BDD operations

Formulates the fault grading problem as a combinatorial problem that amounts to storing and manipulating sets on a special type of binary decision diagrams (BDDs), called zero-suppressed BDDs (ZBDDs), that represent sets in a unique and compact manner. A simple modification of the basic scheme allows us to overcome memory problems that may arise by complex set representation. Experimental results on the ISCAS´85 benchmarks show considerable improvement over all existing techniques for exact PDF grading. The main advantages of the proposed methodology are the simplicity of the approach, in terms of it being expressed by a polynomial number of increasingly efficient BDD-based operations, its organization, and its ability to handle very large test sets