Observation Point Oriented Deterministic Diagnosis Pattern Generation (DDPG) for Chain Diagnosis

Abstract

Scan is a widely usedDesign-for-Testability technique to improve test and diagnosis quality. Many defects may cause scan chains to fail. In this paper, an observation point oriented Deterministic Diagnostic Pattern Generation (DDPG) method was proposed for compound defects, which tolerates the system defects during scan chain diagnosis. Instead of sensitizing multiple paths proposed in our prior work, the proposed new DDPG method directly targets as many observation points as possible to observe the loading error occurred on the targeted scan cell. Experimental results on ISCAS'89 benchmark circuits show that the proposed DDPG method improves the effectiveness and efficiency of diagnosing compound defects, compared to our prior research.