Industrial Case Studies of SoC Test Scheduling Optimization by Selecting Appropriate EDT Architectures

Modern large system-on-chip (SoC) designs typically have hundreds of cores. Each core requires a certain number of input/output test channels. At the chip level, however, the total number of test pins is limited such that all core-level test channels cannot be accessed at the same time. Therefore, hierarchical pattern retargeting is required for SoC test. Test scheduling algorithms can be applied to reduce the total test time. In this paper, we add the EDT architectures as one additional dimension of parameter into the prior test scheduling algorithm. Experimental results based on real case studies show that with the proposed flow, the test time can be further reduced up to approximately 24%.