Random Fault Analysis

A method is presented for performing rapid Test Pattern Evaluation (TPE) using classical statistical analysis. This method is applicable regardless of the types of faults being considered, the likelihood of the fault occuring, or the technique used for fault simulation. A subset of the complete fault list is selected using random sampling techniques, and the fault coverage (percentage of faults detectable by the given test pattern) is estimated and confidence limits about this estimate are given. This technique is useful for LSI as well as VLSI Test Pattern Evaluation in that only a small subset of the total fault list need be analyzed to determine the fault coverage within a few percent.