Patent ID: 9655233
Date: 2017-05-16
CPC Classifications: H05K

Claim:
1. A wiring board comprising: an insulating board formed by laminating buildup insulating layers on upper and lower surfaces of a core insulating plate; a pair of signal external connection pads adjacently arranged in a predetermined direction, on a lower surface of the insulating board; a pair of ground external connection pads arranged on the lower surface of the insulating board so as to be adjacent to the signal external connection pads and so as to be symmetrical across a perpendicular line extending through a middle point between the pair of the signal external connection pads, in a direction perpendicular to the predetermined direction; a pair of signal through-hole conductors penetrating the core insulating plate, and arranged on the perpendicular line so as to be opposed across the middle point between the pair of the signal external connection pads; a pair of ground through-hole conductors penetrating only the same core insulating plate which is penetrated by the signal through-hole conductors, and arranged so as to be adjacent to the signal through-hole conductors; a core ground conductor layer arranged in a region including the ground external connection pad on the lower surface of the core insulating plate, having an opening for collectively surrounding the pair of the signal through-hole conductors, and connected to the ground through-hole conductors; a via-hole conductor extending from the ground external connection pad to the core ground conductor layer in the lower-side insulating layer, to connect each of the pair of the ground external connection pads to the core ground conductor layer on each of both sides provided across the perpendicular line; a pair of lower-side signal connection conductors extending from the signal external connection pads to the signal through-hole conductors in the lower-side insulating layer, to connect the pair of the signal external connection pads to the pair of the signal through-hole conductors through via conductors penetrating the lower-side insulating layer; a pair of strip-shaped wiring conductors formed on a surface of the upper-side insulating layer, and having one ends positioned in a center portion of the insulating board and other ends positioned above the vicinity of the signal through-hole conductors; a pair of upper-side signal connection conductors extending from the signal through-hole conductors to the other ends of the strip-shaped wiring conductors in the upper-side insulating layer, to connect the pair of the signal through-hole conductors to the pair of the strip-shaped wiring conductors through the via conductors penetrating the upper-side insulating layer; a buildup ground conductor layer formed on the surface of the upper-side insulating layer, arranged so as to be opposed to the pair of the strip-shaped wiring conductors, and connected to the ground through-hole conductor through the via conductor penetrating the upper-side insulating layer; and an upper via-hole conductor extending from the ground through-hole conductor to the buildup ground conductor layer in the upper-side insulating layer, to connect the pair of the ground through-hole conductors to the buildup ground conductor layer, wherein the pair of the ground through-hole conductors is arranged across the opening from each other.