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:
Jul. 11, 1995
Filed:
Jan. 27, 1994
Dieter O Marx, Kanata, CA;
Larry K Wong, Kanata, CA;
Northern Telecom Limited, Montreal, CA;
Abstract
A multiple layer printed circuit board and a method of manufacturing multiple layer printed circuit boards which incorporate integral edge shielding in combination with top and bottom shielding to effectively provide a sandwich arrangement within a Faraday Cage. Electromagnetic emissions radiating from an outside surface of either the top or bottom shielding layer are substantially reduced. In one structure, a multiple layer printed circuit board having a sandwich arrangement which includes at least one inner conductive layer for providing a ground plane disposed between the outer shielding layers, the inner conductive layer being electrically connected directly to the edge shielding means and hence to the outer conductive layers. The larger and more continuous surface area provided by the direct connection to the edge shielding effectively provides an electrical connection having a low inductance and hence in operation results in all ground planes having a more constant non-varying potential.