| 摘要 |
PROBLEM TO BE SOLVED: To block electrical coupling of high frequency noise and to shield from a radiation electromagnetic field propagating through the air or a board by arranging a conductor, all solid patterns and via holes while being spaced apart so that they are not connected directly with an internal circuit and not connected with the circuit of filter and connector. SOLUTION: A printed board 100 is secured to box shape 11 screw holes by means of screws thus connecting a solid pattern 106 on the surface side surface layer rigidly with the box shape 111. The box shape 111, the solid pattern 106 on the surface side surface layer, second and third solid patterns 108, 109, and a rear surface layer solid pattern 110 are arranged while being spaced apart by a specified distance without being connected directly with the internal circuit 102. Furthermore, the box shape 111, the solid pattern 106 on the surface side surface layer, the second and third solid patterns 108, 109, and the rear surface layer solid pattern 110 are arranged not to be connected with the circuit of a connector 101 and a filter 103. |
