The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 16, 1999
Filed:
Oct. 22, 1997
Michael J Strum, San Jose, CA (US);
Hewlett-Packard Company, Palo Alto, CA (US);
Abstract
A printed circuit board for minimizing thermally-induced mechanical damage of solder joints electrically connecting electronic components to the printed circuit board. The printed circuit board includes a first substrate, solder pads, and an expansion layer. The first substrate has two substantially parallel major surfaces, and a first coefficient of thermal expansion (CTE). The solder pads are located on one of the major surfaces of the substrate. The expansion layer has a second CTE, different than the first CTE, and is affixed to a portion of one of the major surfaces. The expansion layer is also arranged to provide a predetermined degree of bending for a given temperature change to a portion of the first substrate proximate to the expansion layer and to two of the solder pads, thus forming a concavity in the portion of the substrate.