Effect of Surrounding Air on Board Level Drop Tests of Flexible Printed Circuit Boards

Flexible printed circuit boards (FPCBs) are being introduced in portable electronic devices due to their reduced thickness and ability to bend and adapt to various shapes. In order to be applied in mass production products, FPCBs need to be reliable regarding usage conditions. One of the main causes of failure in electronic devices is impact due to drops during transportation and field use. Typically, manufacturers conduct drop tests to quantify the durability of the components. A common tool to verify the reliability of electronic components in early stages of design is the use of the finite element method (FEM). Because of their reduced thickness and consequent overall stiffness, external effects such as damping as consequence of air resistance may affect structural behavior during impact. This effect might be even more pronounced in confined environments such as the interior of electronic products. This work proposes to develop a multiphysics simulation model to consider fluid-structure interaction between the FPCB and surrounding air. The structural field will be modeled according to current PCB modeling techniques and the surrounding air will be modeled in such a way to consider pressure distribution on FPCB. Experimental drop tests will also be performed to provide data for comparison with FEM model.