Non-Intrusive Self-Test Library for Automotive Critical Applications: Constraints and Solutions

Today, safety-critical applications require self-tests and self-diagnosis approaches to be applied during the lifetime of the device. In general, the fault coverage values required by the standards (like ISO 26262) in the whole System-on-Chip (SoC) are very high. Therefore, different strategies are adopted. In the case of the processor core, the required fault coverage can be achieved by scheduling the periodical execution of a set of test programs or Software-Test Library (STL). However, the STL for infield testing should be able to comply with the operating system specifications without affecting the mission operation of the device application. In this paper, the most relevant problems for the development of the STL are first discussed. Then, it presents a set of strategies and solutions oriented to produce an efficient and non-intrusive STL to be used exclusively during the in-field testing of automotive processor cores. The proposed approach was experimented on an automotive SoC developed by STMicroelectronics.