Automotive Application-driven Vibration Test Approach: Bridging the Gap between Module and Board Level Reliability Test Methods

The ever-evolving automotive architecture is bringing stringent quality and reliability requirements that do not stop at the component level only. Instead, reliability at the board level and module level under harsh environmental conditions also needs to be assessed. To evaluate these reliability risks, accelerated board level reliability test methods must be well-calibrated with the automotive use case or mission profile. This paper investigates the vibration stresses endured by electronic components installed on printed circuit boards (PCB) within compact passenger and lightweight cargo Electric Vehicles (EVs). Electronic components included Ball Grid Array (BGA) and Fan-Out Wafer-Level Packages (FOWLP). Board level vibration measurements at various vehicle speeds, driving modes, road surfaces and locations, including the bumper, chassis, and car ceiling were carried out. The largest impact is caused by the road surface, followed by the vibration measurement location, and car-to-car type variation. The largest vibrations were observed at the bumper of the analyzed EV. Then, accelerated vibration tests were defined and conducted in laboratory test settings, both at the module and board levels. The board level tests exhibited earlier failures compared to the module level tests. However, this outcome is module-specific and may vary with different modules. Furthermore, vibration testing was conducted using both random vibration and swept sine tests. Here, swept sine testing induces earlier solder joint failure when compared to random vibration testing. Finally, the user mission profile measured in electric vehicles was correlated to the reliability test performance of the BGA package in accelerated reliability test conditions. The selected vibration test parameters are expected to cover the solder joint reliability risks in the analyzed automotive application.