Effects of the strain transmission from the main board to the installed electronic components

摘要

Optimization of electronic assembly pins quantityminimizes mount stress effect on electronic components.Developed high through-hole installation technologyof electronic components on the main board providessignificant reducing of the strain transmitted to electroniccomponents in comparison with standard low through-holeand surface-mount installation.The strain in integrated circuits mounted on themain board depends on rigidity and design of their pins. Theoffered soft installation technology 3-4 times reduces strainin comparison with the solid installation.Hollow electronic modules are more sensitive tomain board deformation than the encapsulated ones. Thestrain in electronic modules changes depending on durationof the main board deformation they are installed on.The deformation produced by the main board ontocontact pads (assumed to be weak links of the whole structure)in electronic modules is found to be dependent on connectingleads or pins, and decreasing their rigidity or applyingcompensators can significantly reduce the influence ofthe main board onto the electronic components. The measuredstrain in case of soft installation technology is 3-4 timeslower than the strain in solid installation.The developed method for acceptable limit specificationof PCB warpage is applicable for any design of electronicmodules and any installation technology.For the more detailed research of the strain in electroniccomponents, which are relatively small objects, thefurther research will be aimed at application acoustic emissionmethod in order to develop methods for strength diagnosticsand predicting possible breakages at the stage longbefore a fatal destruction in electronic packages.