| 摘要 |
<p>A printed circuit board is disclosed which comprises a plurality of non-through holes into thickness direction in one surface of the board, a plurality of through holes in some of the non-through holes to open through opposite surface of the board and having a smaller inside diameter than the non-through holes, a plurality of first conductive lands on the periphery of the openings of the non-through holes in one surface of the board, a plurality of second conductive lands on the periphery of the openings in opposite surface of the through holes and having the smaller outside diameter than the second lands on the periphery of the openings of the non-through holes, a conductor layer in inside wall of the non-through holes and the through holes for connecting the first lands in one surface and the second conductive lands in opposite surface of board, and conductive patterns formed in one surface and opposite surface of the board respectively, which invention is capable of including the great number of the conductive patterns as necessary for mounting the electric component such as PGA or HPC without multilayering the board or going around of the conductive patterns, because of the greater number of the spaces between the second lands can be formed in opposite surface.</p> |
