T2- TAM:Reusing infrastructure resource to provide parallel testing for NoC based Chip

Reusing network-on-chip (NoC) as test-access-mechanism (TAM) has been adopted to transfer test data to embedded cores. However, an observation shows that compared to NoC-reuse TAM, some bus-based TAM are able to achieve better results in test time due to its fine-grained scheduling unit. This paper proposed a new TAM named Test Tree(T²). T²TAM could be built by reusing the hardware resources of routers instead of reusing the packet-based NoC. Though implementing DFT design on routers, the T2TAM can achieve wire utilization and adopts fine-grained basic scheduling. Besides, to address the problem of testing large number of homogeneous cores, T²-TAM is proposed to facilitate multicasting stimuli to homogeneous cores to save test time. Experimental results show that the test cycles could be reduced up to 38% in comparison with the work reusing NoC as TAM with only 0.3% DFT overhead.