Characterization and Modeling of Printed Wiring Board Warpage and its Effect on LGA Separable Interconnects

Abstract

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.

Influence of printed circuit board thickness in wave soldering

“…Nonetheless, most of these studies concentrated on the solder re ow process through experiments [2] and simulations [3]. In literature, many researchers used the Finite-Element Method (FEM) [3][4][5] to investigate the PCB and substrate warpage.…”