Delay testing for non-robust untestable circuits

Recently published results have shown that, for many circuits, only a small percentage of path delay faults is robust testable. Among the robust untestable faults, a significant percentage of them is not non-robust testable either. In this paper, we take a closer look at the properties of these non-robust untestable faults with the goal of determining whether and how these faults should be tested.<
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