| 摘要 |
PURPOSE:To get a multipurpose via suitable for high-density mounting by dividing the through hole plating into a plurality of parts in circumferential direction, and enabling the connection between many sets of conductor layers with one viahole. CONSTITUTION:In a viahole consisting of through hole plating, which connects the conductor layers of a multilayer printed wiring board 2, the through hole plating is divided into a plurality of parts 10a, 10b, 10c, and 10d, and the connection between many sets of conductors are made possible with one via. Out of the viaholes divided in the circumferential direction, the viahole 10b connects the conductor layers 4a made at the surface of a multilayer printed wiring board 2 with the conductor layer 4b made inside, while the viahole 10a connects the conductor layer 4c made at the bottom of the multilayer printed wiring board 2 with the conductor layer 4d made inside. In this case, the viaholes 10a and 10b are not in contact with each other, so those are capable of being different potentials. Accordingly, the exchange of signals between the conductor layers 4a and 4c and the exchange of the signals between the conductor layers 4c and 4d can be done independently. |
