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:
Jun. 21, 1994
Filed:
Mar. 31, 1993
William F Weber, Allen, TX (US);
Alcatel Network Systems, Inc., Richardson, TX (US);
Abstract
An EMI internal shield made of an electrically conductive material that absorbs and reflects electromagnetic interference (EMI) signals associated to fit with an EMI shield top cover. The EMI internal shield is formed to fit without solder or welding as an EMI shield apparatus over EMI susceptible electronic circuitry on a printed circuit board. The EMI internal shield apparatus not only shields circuitry from EMI sources external to the printed circuit board, but also isolates certain electronic circuits from other electronic circuitry on the printed circuit board. Additionally, the EMI internal shield permits the communication of desired electromagnetic radio frequency and electrical signals to the circuitry inside the shield. The EMI internal shield apparatus includes the use of an electrically conductive layer that is integral to the top of the printed circuit board and which includes conductive channels that penetrate the printed circuit board. The channels prevent EMI from passing through the printed circuit board to the shielded electronic circuits. Also, the channels receive tangs found on the EMI internal shield. The tangs are positioned to prevent EMI from passing through the juncture of the EMI internal shield with the conductive layer. As EMI signals reach the EMI internal shield, they are absorbed and conducted to an electrical ground or reflected from the EMI internal shield. Signal trace openings through the conductive layer permit electrical leads from the electronic circuitry to connect to external circuitry.