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:
Aug. 09, 1994
Filed:
Jan. 06, 1992
U.S. Philips Corporation, New York, NY (US);
Abstract
The invention relates to a multilayer printed circuit board, in particular, for high-frequency operation, having least an outer, plane dielectric layer for accommodating interconnection paths of equal cross-section and component as well as further alternately provided metallic and dielectric layers for forming a reference earth and for the voltage supply to said interconnection paths and components via plated-through holes. In order to obtain a plane surface for the interconnection paths and predetermined areas on the printed circuit board, which areas have different characteristic impedances when interconnection paths having the same cross-section are used, at least the first metal layer comprises at least one window and the subsequent metal layer has a metal island corresponding to the area of the window, which island is connected to the reference earth via a buried plated-through hole, and the characteristic impedance of the interconnection paths is a function of the resulting thickness of the effective dielectric layers the number of which is increased in the area of the window.