Parallelized Network-on-Chip-Reused Test Access Mechanism for Multiple Identical Cores

This paper proposes a new network-on-chip (NoC)-reused test access mechanism (TAM) for testing multiple identical cores. It can test multiple cores concurrently and identify faulty cores to derate the chip by excluding the core. In order to minimize the test time, the TAM utilizes the majority value of test response data. All of the cores can thereby be tested in parallel and test costs (in both test pins and test time) are exactly the same as those for a single core. The hardware overhead is minimized by reusing the NoC infrastructures and transfer-counters are designed as a majority analyzer. The experimental results in this paper show that the proposed TAM can test multiple cores in the same time as a single core and with negligible hardware overhead.