Path delay fault diagnosis using path scoring

With the increasing complexity of VLSI devices, more complex faults have appeared. The process of locating input-output paths in the chip that caused the delay fault is termed as delay-fault diagnosis. In this paper, we propose a path delay fault diagnosis algorithm using path scoring. The proposed diagnosis algorithm utilizes reasoning-based diagnosis technique and stuck-at fault diagnosis results to improve diagnosis the resolution of delay-fault diagnosis. We propose a path scoring algorithm to increase first-hit-rate (FHR). Experimental results for ISCAS85 and full-scan version of ISCAS89 benchmark circuits prove the accuracy of the proposed algorithm.