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:
Oct. 14, 2008
Filed:
May. 14, 2002
Arthur R. Alexander, Valley Center, CA (US);
James L. Knighten, Poway, CA (US);
Jun Fan, Escondido, CA (US);
Arthur R. Alexander, Valley Center, CA (US);
James L. Knighten, Poway, CA (US);
Jun Fan, Escondido, CA (US);
Teradata US, Inc., Miamisburg, OH (US);
Abstract
A circuit board includes multiple signal layers, in which signal lines are routed, and reference plane layers, in which power reference planes are provided. To connect signal lines at different signal layers, vias are passed through at least one signal layer and at least one reference plane layer. At the one signal layer, a first clearance (or anti-pad) is defined around the via. At the reference plane layer, a second clearance is defined around the via. The second clearance is larger in size than the first clearance to match the impedance of the via as closely as possible with the impedance of a signal line the via is electrically connected to.