Flexible test bench to study the reliability of electronic assemblies

Robustness and reliability for electronic boards are key issues, especially in the aeronautics industry. To study the reliability of the assembly, accelerated tests are performed on daisy chain components assembled on Printed Circuit Board (PCB). Times to failure of components need to be accurately detected to propose relevant fatigue and reliability models. To electrically monitor the daisy chains, a flexible event detector has been developed by EADS Innovation Works. Its aim is to detect micro-events in a solder joint. Indeed, despite the crack initiation and propagation, the solder joint can still conduct electrical current intermittently. Nevertheless, the solder joint is not considered as reliable because it is not able to fulfill its function in any case. Firstly, this paper presents the characteristics of the flexible event detector. A part of the system records continuously micro-events, for a large number of channels. Then, a custom interface analyse the data recorded by the multi channels system to identify those which correspond to standards (such as IPC-SM-785) or a custom criteria. To illustrate this method and validate the event detector, some experimental vibration tests were performed. Several components electrically failed during the tests and were precisely detected by the flexible event detector. Finally, a comparative vibration testing is performed between a commercial event detector system and the EADS IW one to identify the detection capacities of each solution.