EXOP (Extended Operation): A new logical fault model for digital circuits

A gate-level fault model for digital circuits is proposed that generalizes previous models and is expected to model defects not included in other fault models. Theoretical discussions and experimental results are presented to show the effectiveness of a test set for the new fault model in achieving very high coverage of commonly used single and multiple faults. It is shown that test generation for this model can be done by a simple reordering of a stuck-at fault test set (possibly repeating some of the stuck-at tests). Reordering is based on defining a graph over the set of all stuck-at tests and finding an Euler cycle in the graph in time which is polynomial in the number of tests.