Diagnosis of Systematic Delay Failures Through Subset Relationship Analysis

Delay faults have become increasingly important in modern designs due to decreasing technology node size and increasing operation frequency. However, diagnosis of delay faults can be challenging since there are typically few failing bits in the test failures. In this work, a two-phase flow is presented to identify systematic delay failures and improve their corresponding diagnosis resolution. First, the subset relationships among test failures are analyzed to identify systematic defects. Then, representative test failures in the subset relationships are selected to diagnose the defect behavior. Experiments on two cores of an industrial design with three cases show over 33×, 69×, and 8× improvement on delay fault diagnosis resolution. Furthermore, the proposed technique can be easily integrated with commercial tools.