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:
Mar. 22, 2005
Filed:
Apr. 29, 2003
Yuming Tao, Kanaka, CA;
Vernon R. Little, White Rock, CA;
Yuming Tao, Kanaka, CA;
Vernon R. Little, White Rock, CA;
PMC-Sierra, Inc., , CA;
Abstract
Gridded I/O pads for flip-chip packages in which a coaxial-like solder bump pad configuration is used in which the I/O pads closest to the signal or bump pad are power or ground pads. The ground pads surrounding the signal pad form a coaxial-like pad configuration for impedance matching at the transition from die to package substrate. The ground pads surrounding the signal pad may be connected by a metal trace to form a ground pad ring. The invention employs conductor-backed ground coplanar waveguides (GCPW), which match impedance at connections between I/O cells and signal pads to enhance signal transmission, avoid reflection and leakage, and provide superior electromagnetic shielding. The present invention also supports high quantities of I/Os for a given die size, and supports flexible power and ground placement.