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:
May. 20, 2003
Filed:
Mar. 08, 2001
Steven H. C. Hsieh, Cupertino, CA (US);
Xilinx, Inc., San Jose, CA (US);
Abstract
A method and assembly for testing multiple IC packages for solder joint fractures that occur in response to thermal cycling. A test PCB is fabricated with contact pads arranged to match a BGA IC package footprint, wherein pairs of the contact pads are linked by conductive traces (lines) to form a lower portion of a daisy chain. The BGA IC package is modified to link associated pairs of solder balls, e.g., using wire bonding to form an upper portion of the daisy chain. Mounting the BGA IC package on the test PCB completes the daisy chain. By alternating between the test PCB contact pads that are linked by conductive traces and the solder balls that are linked by wire bonding, the daisy chain provides a conductive path that passes through all solder balls of the BGA IC package.