A Novel Controllable BIST Circuit for embedded SRAM

With increasingly stringent requirements for memory test, the complexity of the test algorithm is increasing. This will make BIST (Build-In-Self-Test) circuit more complex and the area of BIST circuit larger. This paper proposes a novel controllable BIST circuit. The controllable BIST circuit provides a cost-effective solution that supports a variety of March algorithms and SRAM embedded testing operation modes. It controls the test patterns with three additional input ports. And it indicates the algorithm progress, the test result and the number of fails with three output ports. To achieve test patterns generation, analy-sis and test results recording, the proposed BIST circuit contains five internal functional modules, which are Address Gener-ator, Control Generator, Data Generator, Data Comparator and Fail Accumulator. The test patterns of the proposed BIST cir-cuit are controlled by external signals. It is not only suitable for any existing march algorithms but also leaves room for ex-tension if needed.