| 摘要 |
PROBLEM TO BE SOLVED: To manufacture a thicker printed wiring board and increase flexibility of selection of lead length of an electronic component mounted on a casing structure of mounted electronic equipment and on printed wiring. SOLUTION: A printed wiring board 1 having a plurality of conductor layers has conductor layers L1 to L8, 8 layers in total. The conductor layers L1 and L8 constitute a surface and rear surface outer layer conductor layer 2, the conductor layers L2 to L4 constitute an inner high wiring density conductor layer 3, and the conductor layers L5 to L7 are an inner low wiring density conductor layer 4. A through-hole 6 provided in the printed wiring board 1 includes a copper plated coated film layer 5 formed thereon. The through-hole 6 has a smaller diameter at a portion of the inner conductor layer 3 of the high wiring density conductor layers L2 to L4 while it has a larger diameter at a portion of the inner conductor layer 4 of the lower wiring density conductor layers L5 to L7 than the conductor layers L2 to L4. COPYRIGHT: (C)2007,JPO&INPIT |
