The impact of boundary scan on board test

Three categories of approaches to board test in manufacturing today are discussed: as a sorting process; as a repair driver: and as a process monitor. The costs associated with each are briefly examined. Elements in the overall testing and manufacturing process that can sabotage the success of a board-test operation are described. They are inaccuracies, misdiagnosis, test-repair looping, and handling-induced failures. Some industry trends that can threaten a manufacturer's ability to control the board-manufacturing process, namely, ASICs, surface-mount technology/tape automated bonding, miniaturized components, and node counts, are considered. The ability of boundary scan to enhance fault diagnosis, reduce test-repair looping, and enable standardized testing and the reuse of tests is discussed. Future trends in boundary-scan testing are indicated.<<ETX>>