| 摘要 |
PROBLEM TO BE SOLVED: To provide a mutilayer printed circuit board which can improve impedance matching even when signal frequency is high. SOLUTION: In the multilayer printed circuit board provided with a plurality of signal layers 1 having signal lines 11 provided therein, a through-hole 21 for mutual connection of the signal lines 11 of the different signal layers 1, and ground through-holes 41 for electric connection between a plurality of ground layers of the board or between a plurality of wiring layers thereof, the signal layer 1 is provided with lands 31 for connecting the through-holes 31 and the signal lines 11. The outer periphery of the land 31 has a maximum diameter part 32 spaced by a maximum distance from the center of the land 31 and a small diameter part spaced by a smaller distance than the maximum diameter part 32 from the center of the land 31. A part of the outer periphery of the land facing the ground through-hole 41 closest to the center of the land 31 is formed as a small diameter part 33. COPYRIGHT: (C)2004,JPO&NCIPI |
