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. 13, 2008
Filed:
Jun. 14, 2005
Naoki Nakamura, Kawasaki, JP;
Midori Kobayashi, Kawasaki, JP;
Naoki Nakamura, Kawasaki, JP;
Midori Kobayashi, Kawasaki, JP;
Fujitsu Limited, Kawasaki, JP;
Abstract
A via is formed in a printed circuit board to penetrate through an insulating layer. A guard pattern, made of an electrically-conductive material, extends on the front surface of the insulating layer along a circle concentric with the via. An electrically-conductive body extends from the guard pattern in the insulating layer along an imaginary cylinder concentric with the via. The guard pattern of the printed circuit board serves to control the characteristic impedance of the via at the front surface of the insulating layer. The electrically-conductive body contributes to a better control of the characteristic impedance of the via. The via is allowed to reliably enjoy a better impedance matching than ever. Noise can sufficiently be suppressed in electric signals running through the via.