IP cores that are embedded in SoCs usually include embedded test compression hardware. When multiple cores are embedded in a SoC with limited tester-contacted pins, there is a need for a structured test-access mechanism (TAM) architecture that allows compressed test data stimuli and responses to be efficiently distributed to the embedded cores. This paper presents SmartScan, a TAM architecture that is based on time-domain multiplexing of compressed data. Results on industrial designs show that high quality compressed ATPG patterns can be efficiently re-applied in a very low-pin SoC test environment with very low overhead.

No abstract

No abstract

No abstract

Designs using advanced low power techniques like MultiSupply Multi-Voltage and PowerShutoff bring with them a new set of challenges that manufacturing test must deal with carefully. These designs have low power components -isolation cells, retention flops, level shifters, power switches, etc., -that must be tested not only structurally but also addressing their behavior across multiple power modes. This paper describes the challenges in testing the key low power components and proposes novel solutions. The defective behavior of state retention logic is modeled to enable fault grading. ATPG modeling of defective behavior of isolation logic and level shifters is described for designs that support multiple supply voltages and power shutoff. The solutions are supported by experimental results on industrial designs.