Machine Learning-Based Test Pattern Generation for Neuromorphic Chips

The demand for neuromorphic chips has skyrocketed in recent years. Thus, efficient manufacturing testing becomes an issue. Conventional testing cannot be applied because some neuromorphic chips do not have scan chains. However, traditional functional testing for neuromorphic chips suffers from long test length and low fault coverage. In this work, we propose a machine learning-based test pattern generation technique with behavior fault models. We use the concept of adversarial attack to generate test patterns to improve the fault coverage of existing functional test patterns. The effectiveness of the proposed technique is demonstrated on two Spiking Neural Network models trained on MNIST. Compared to traditional functional testing, our proposed technique reduces test length by 566x to 8,824x and improves fault coverage by 8.1% to 86.3% on five fault models. Finally, we propose a methodology to solve the scalability issue for the synapse fault models, resulting in 25.7x run time reduction on test pattern generation for synapse faults.