OPERATION AND MANUFACTURE FOR COMPUTER AND PRINTED CIRCUIT BOARD

摘要

PURPOSE: To separate a signal which is sensitive to a noise from environment where there are many noises by providing two earth planes which put a plane where a signal that is sensitive to a noise is sent in between and connecting the two planes around the plane to form a Faraday cage. CONSTITUTION: A printed-circuit board 10 is completely enclosed by a Faraday cage. A 1st plane 11 is mounted on the board 10 and connected to a 2nd earth plane 12 placed on the bottom of the board 10 by means of plural vias 13. The vias 13 are substantially placed around the two planes 11 and 12 in the same way. The Faraday cage consists of the two planes 11 and 12 which effectively separate a pair of signal lines 14 and 15 from the outside interference, and the connection vias 13. Dielectric materials which constitute the planes 11 and 12 and the signal lines 14 and 15 are separated by insulation planes 16 made by means of a usual technique. Thereby, a signal which is sensitive to a noise can be separated from environment where there are many noises.