Printed electronics (PE) enable lightweight, flexible, and low-cost devices for the Internet of Things (IoT) and wearable applications. Compared to conventional silicon-based electronics, PE trades peak performance for advantages in cost efficiency, mechanical flexibility, and large-area fabrication. However, its manufacturing processes remain unreliable and are prone to structural defects and variation due to inherent limited control in additive manufacturing. Printed neuromorphic circuits (pNCs) leverage the benefits of PE for on-demand analog edge computation in target applications but remain vulnerable to such defects. Diagnostic testing is therefore essential not only for detection but also for localizing faults to specific subcircuits and regions in the layout, a step critical for guiding yield improvement and reducing the cost of downstream inspection. We propose a diagnostic test pattern generation (DTPG) framework for fault localization in pNCs under black-box access. While ATPG is typically formulated as an optimization problem for fault detection, our approach extends this formulation by explicitly optimizing for fault distinguishability. On ten UCI datasets, the framework achieves up to 20.7% higher diagnostic coverage with a reduction of up to 3.6 times the number of undetectable subcircuits than detection-only test sets, while constraining the number of patterns to reduce storage overhead. These results demonstrate effective fault localization and establish a foundation for finer-grained, component-level diagnosis in future work.

As artificial intelligence becomes integral in domains like healthcare and autonomous systems, dedicated hardware accelerators are becoming increasingly essential. These are structurally tested at manufacturing, independent of the AI model executed. However, in-field reliability demands model-based functional testing using the Deep Neural Networks (DNNs) deployed during inference. Faults in DNNs can degrade performance, making in-field testing critical under memory and time constraints. We propose a framework to generate a set of test patterns according to memory constraints while ensuring effective fault coverage of the fault distribution through joint optimization of patterns. Results show 100% coverage, outperforming random and adversarial inputs.

Deep neural networks (DNNs) have emerged as an effective approach in many artificial intelligence tasks. Several specialized accelerators are often used to enhance DNN's performance and lower their energy costs. However, the presence of faults can drastically impair the performance and accuracy of these accelerators. Usually, many test patterns are required for certain types of faults to reach a target fault coverage, which in turn hence increases the testing overhead and storage cost, particularly for in-field testing. For this reason, compression is typically done after test generation step to reduce the storage cost for the generated test patterns. However, compression is more efficient when considered in an earlier stage. This paper generates the test pattern in a compressed form to require less storage. This is done by generating all test patterns as a linear combination of a set of jointly used test patterns (basis), for which only the coefficients need to be stored. The fault coverage achieved by the generated test patterns is compared to that of the adversarial and randomly generated test images. The experimental results showed that our proposed test pattern outperformed and achieved high fault coverage (up to 99.99%) and a high compression ratio (up to 307.2$\times$).

Deep Neural Networks (DNNs) have gained considerable attention lately due to their excellent performance on a wide range of recognition and classification tasks. Accordingly, fault detection in DNNs and their implementations plays a crucial role in the quality of DNN implementations to ensure that their post-mapping and infield accuracy matches with model accuracy. This paper proposes a functional-level automatic test pattern generation approach for DNNs. This is done by generating inputs which causes misclassification of the output class label in the presence of single or multiple faults. Furthermore, to obtain a smaller set of test patterns with full coverage, a heuristic algorithm as well as a test pattern clustering method using K-means were implemented. The experimental results showed that the proposed test patterns achieved the highest label misclassification and a high output deviation compared to state-of-the-art approaches.

Deep neural networks (DNNs) have achieved record-breaking performance in various applications. To reduce the energy footprint and increase performance, DNNs are often implemented on specific hardware accelerators, such as Tensor Processing Units (TPU) or emerging Memristive technologies. Unfortunately, the presence of various hardware faults can threaten these accelerators' performance and degrade the inference accuracy. This necessitates the development of efficient testing methodologies to unveil hardware faults in DNN accelerators. In this work, we propose a test pattern generation approach to detect fault patterns in DNNs for a common type of hardware fault, namely, faulty weight value representations on the bit level. Contrary to most related works which reveal faults via output deviations, our test patterns are constructed to reveal faults via misclassification which is more realistic for black-box testing.