Error diagnosis of sequential circuits using region-based model

Algorithms to locate multiple design errors using region-based model are studied for both combinational and sequential circuits. The model takes locality aspect of errors and is based on, a 3-value, non-enumerative analysis technique. Studies show the effectiveness of the region based model for gate connection and gate substitution errors. For sequential circuits, we try to locate the time frame at which the error was first excited, by re-simulating as few vectors as possible preceding the erroneous vector in a fully initialized circuit to carry out the diagnosis. Experimental results on benchmark circuits are used to demonstrate rapid and accurate locating of multiple errors.