Patent ID: 7326856

Claim:
A multi-layer wiring board comprising: a plurality of through holes extending through a thickness of the multi-layer wiring board; a plurality of wiring layers, each wiring layer comprising board wiring for conducting electrical signals, some of the board wiring of the wiring layers being electrically connected to the through holes; at least a first through hole and a second through hole being electrically connected, the first through hole and the second through hole being adjacent to each other and separated by a distance less than the thickness of the multi-layer wiring board wherein the first through hole is connected to board wiring of a predetermined wiring layer, and the second through hole transmits a signal carried by the board wiring to components other than on the multi-layer wiring board; and a wiring layer in an intermediate portion of the multi-layer wiring board, and a length of a connection pattern connecting upper end portions of the first and second through holes to each other in the uppermost layer is longer than a length of a connection pattern connecting lower end portions of the first and second through holes to each other in the lowermost layer.