Robert C German

US Patent:

56843402, Nov 4, 1997

Filed:

Feb 16, 1996

Appl. No.:

8/602404

Inventors:

Xavier Soler - Barcelona, ES
Richard Lewis - Barcelona, ES
Andrew M. Frost - Barcelona, ES
Robert F. German - Boulder CO

Assignee:

Hewlett-Packard Company - Palo Alto CA

International Classification:

H05K 900

US Classification:

307 91

Abstract:

An arrangement for preventing electromagnetic interference is aimed at attenuating electromagnetic emissions in electronic apparatus, especially those having a printed circuit board, a conductive enclosure, and requiring external connections to other devices. The arrangement comprises a division of the printed circuit board into two zones, a first zone having sources of unwanted electromagnetic energy, and a second zone which is electrically connected with the first zone via conductors which allows the second zone to connect to other devices. Filtering devices are incorporated into the printed circuit board and, in conjunction with integrated conducting zones, provide suitable connections to a metallic protecting enclosure in order to remove or to attenuate unwanted signal components from the signals being transmitted from the first zone to the second zone via the conductors. The protecting enclosure components enclose at least portions of the first zone of the printed circuit board for shielding direct electromagnetic emissions originating from the first zone.