Printed Circuit Board Assembly Test Process and Design for Testability

The trend in Printed Circuit Board Assembly technology is towards higher complexity, many boards have significantly more components and solder joints today than just a few years ago. In addition, board assembly process variations may lead to board failures due to the change of process parameters. The sooner process and electrical defects are caught, the lower the total cost of ownership will be. Defect finding and analysis at early manufacturing stages are critical to lower cycle time and cost for high-volume production. Therefore, a key challenge facing electronics manufacturers of high complexity boards is the issue of board test strategy. An effective board test strategy can be critical in determining a company's ability to succeed in an environment of extreme cost and time to market pressures, and requirement to faster volume ramp with higher yield and quality. Design for testability is a key to lower life cycle cost of the product from design, manufacturing, and field support. Poor design for testability makes product testing difficult and with low test coverage. More and more failures escape to the field and would create a larger bone-pile of boards that need to be debugged and repaired. In order to improve quality, a special attention should be given to design for testability at early design stages while defining good test process strategy for the high-volume production.