| 主权项 |
1. A device for attenuating propagation and reception of electromagnetic interference for a system, the system comprising a printed circuit board mounted to a chassis by at least one fastener, the fastener establishing an electrical connection between the printed circuit board and the chassis, the device comprising:
a first substantially annular conductive material having a first central opening, the first central opening sufficient to substantially surround the fastener and maintain the electrical connection between the printed circuit board and the chassis; a second substantially annular conductive material concentric with the first conductive material, the second conductive material having a second central opening sufficient to substantially surround the fastener and maintain the electric connection between the printed circuit board and the chassis; a substantially annular impedance material between and adjacent to the first conductive material and the second conductive material, the impedance material sufficient to attenuate the electromagnetic interference from the system; a substantially annular, insulator material, inner support structure between and adjacent to the first conductive material and the second conductive material, the inner support structure having an outer diameter smaller than an inner diameter of the impedance material and surrounded by the impedance material, the inner support structure having a third central opening sufficient to substantially surround the fastener; a substantially annular, insulator material, outer support structure between and adjacent to the first conductive material and the second conductive material, the outer support structure having an inner diameter larger than an outer diameter of the impedance material, the outer support structure substantially surrounding and contacting the impedance material. |
