The paper presents a study on printed wiring board (PWB) warpage caused by the mechanical fastening of separable interconnects, known as land grid array (LGA) package assemblies. Out-of-plane displacement of the PWB were measured and characterized, as well as force-per-pin values of the LGA, and correlations were made between the two. Classical laminate theory was utilized to describe the warpage behavior of the assembly and a model was presented to solve the out-of-plane displacements. An overall assessment of the assembly was made and compared to the mechanical specification of the LGA.
Issue Section:
Research Papers
Keywords:
assembling,
electric connectors,
laminates,
printed circuits,
electronics packaging,
joining processes
Topics:
Laminates,
Printed circuit boards,
Warping,
Approximation,
Sensors,
Pressure,
Displacement,
Stress
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.Copyright © 2005
by American Society of Mechanical Engineers
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