Genetic method for compressed skewed-load delay test generation

Complex system-on-chips (SOCs) require low-overhead testability methods to keep the test cost at an acceptable level. Skewed-load tests seem to be the appropriate way to test delay faults in these SOCs because the test application requires only one storage element per scan cell. Compressed skewed-load test generator based on genetic algorithm is proposed for wrapper-based logic cores of SOCs. Deterministic population-initialization is used to ensure the highest achievable transition delay fault coverage for the given wrapper and scan cell order. The developed genetic algorithm performs test data compression by generating test vectors containing already overlapped test vector pairs. The experimental results show high fault coverages, decreased test lengths and better scalability in comparison to recent methods.