Hierarchical built-in test: an alternative test and repair strategy

This paper looks at the capabilities of Built-in Test (BIT) at various levels of assembly (disassembly) and will examine how strategies can be developed to locate and diagnose faults without the need for external automated test equipment (ATE). Various test stages will be considered for both manufacturing and maintenance. It will be shown how hierarchical BIT can ensure that faults are diagnosed at the most appropriate level of repair: system, board, or IC. This capability will in turn create a flexibility in repair strategies, with component level repair possible even by end users.