Design rules for portable electronic device are continuously striving for thinner printed wiring assemblies (PWAs) and smaller clearances because of ever-increasing demand for functionality and miniaturization. As a result, during accidental drop and impact events, there is an increased probability of internal secondary impact between a PWA and adjacent internal structures. In particular, compared to the initial impact, acceleration pulses caused by contact during secondary impacts are typically characterized by significant increase of amplitudes and frequency bandwidth. The resonant response in the thickness direction of printed wiring boards (PWBs) (termed the dynamic “breathing mode” of response, in this study) acts as a mechanical bandpass filter and places miniature internal structures in some components (such as microelectromechanical systems (MEMS)) at risk of failure, if any of them have resonant frequencies within the transmitted frequency bandwidth. This study is the first part of a two-part series, presenting qualitative parametric insights into the effect of secondary impacts in a PWA. This first part focuses on analyzing the frequency spectrum of: (i) the impulse caused by secondary impact, (ii) the energy transmitted by the dynamic “breathing” response of multilayer PWBs, and (iii) the consequential dynamic response of typical structures with high resonant frequencies that are mounted on the PWB. Examples include internal deformable structures in typical surface mount technology (SMT) components and in MEMS components. The second part of this series will further explore the effects of the breathing mode of vibration on failures of various SMT components of different frequencies.
Influence of Secondary Impact on Printed Wiring Assemblies—Part I: High-Frequency “Breathing Mode” Deformations in the Printed Wiring Board
Cycle Engineering (CALCE),
Mechanical Engineering Department,
University of Maryland,
College Park, MD 20742
Contributed by the Electronic and Photonic Packaging Division of ASME for publication in the JOURNAL OF ELECTRONIC PACKAGING. Manuscript received September 26, 2015; final manuscript received January 6, 2016; published online March 10, 2016. Assoc. Editor: Jeffrey C. Suhling.
- Views Icon Views
- Share Icon Share
- Cite Icon Cite
- Search Site
Meng, J., and Dasgupta, A. (March 10, 2016). "Influence of Secondary Impact on Printed Wiring Assemblies—Part I: High-Frequency “Breathing Mode” Deformations in the Printed Wiring Board." ASME. J. Electron. Packag. March 2016; 138(1): 010914. https://doi.org/10.1115/1.4032495
Download citation file:
- Ris (Zotero)
- Reference Manager