On NBTI-induced Aging Analysis in IEEE 1687 Reconfigurable Scan Networks

The Negative Bias Temperature Instability (NBTI) phenomenon is one of the main reliability issues in today’s nanoelectronic systems. It causes increase in threshold voltage of pMOS transistors, thus degrading signal propagation delay in logic paths between flip-flops. Recently, IEEE published a new standard IEEE 1687 for Reconfigurable Scan Networks (RSN) to facilitate access to embedded instrumentation within an integrated circuit. In the field, the RSN infrastructure is often exploited for fault-management in failure-sensitive critical parts of the system. Therefore, the severity level of a fault in the RSN itself is very high, thus, amplifying the impact of the reliability issues caused by the aforementioned effect. To the best of the authors’ knowledge, no approach has been proposed to investigate or address this issue so far. In this paper, we analyze the effect of NBTI-induced aging in RSNs from architectural and operational (functional) perspectives and present a novel technique to mitigate the degradation. The methodology is demonstrated on a case-study example and the effectiveness of our approach is evaluated on a sub-set of ITC2016 benchmark RSN designs.