Determining LGA Contact Design Specifications by Investigating Sensitivity of LGA Contact Performance to LGA Contact Geometric Tolerance

Abstract

This paper presents a numerical DOE to investigate the sensitivity of the mechanical performance of LGA contacts, e.g. contact working range, wiping distance and force, to four key design parameters: contact free height, contact thickness, contact material yield strength and the coefficient between the contact and its landing pad. Multiple cases were analyzed and the normalized response surfaces of the performance are presented. By keeping the linear terms of the response surfaces, the performance variances relative to the nominal can be estimated. The methodology using the estimated variances to define LGA contact design specification is also presented.