Performance Standard
Industry test methods that establish uniform guidelines for evaluating the reliability of surface mount solder attachments under thermal cycling conditions govern the acceptance of new board designs. Adhering to IPC-9701 qualification requires assemblies to undergo specific temperature profiles while their electrical continuity is monitored. This standard defines the parameters for temperature ranges, dwell times and transition rates used during testing.
These guidelines cover a wide range of surface mount packages, including ball grid arrays and leadless chip carriers, ensuring that different components are subjected to comparable thermal stress environments.
Evaluation Method
Testing involves mounting the target packages onto specific test boards and subjecting them to standardized temperature cycles until a predetermined number of cycles is reached or failure occurs. Solder joint resistance is continuously monitored to detect open circuits or resistance increases. The resulting data is analyzed using Weibull distribution models to determine the characteristic life of the solder attachments.
Acceptance Criteria
Pass or fail decisions are based on the number of cycles completed without a solder joint failure. A joint is considered failed when its resistance increases by twenty percent or when electrical continuity is lost. Manufacturers use this standard to validate their assembly processes and guarantee product reliability.
