Efficient Global Fault Collapsing for Combinational Library Modules

—Fault collapsing is the process of reducing the number of faults by using redundance and equiva-lence/dominance relationships among faults. Exact global fault collapsing can be easily applied locally at the logic gates, however, it is often ignored for library modules due to its high demand of resources such as execution time and/or memory. In this paper, we present an efficient and exact global fault collapsing method for library modules that uses both binary decision diagrams and fault simulation with random vectors. Experimental results show that the new method reduce the number of faults drastically with feasible resources and produce significantly better results than existing approaches.