Handling Pattern-Dependent Delay Faults in Diagnosis

Traditionally, diagnosis methods use static models for delay defects, while there exists a class of faults including cross-coupling capacitance and resistive shorts exhibiting different effects on path delays with different input patterns. Blindly treating such faults will lead to skewed results for locating defects. In this paper, the authors discuss the method to handle these faults without explicitly modeling each type of faults. In the process, the authors differentiate failed delay paths into two categories: static and pattern-dependent. The authors further explore these information to list possible candidates (including coupling defects) causing timing failures for further analysis. The experimental results show that average rankings of suspects are 2.1 and 4.6 for failing segments and coupling pairs, respectively.