Patent ID: 8110751

Claim:
A printed circuit board which includes a first side surface and a second side surface on which a plurality of semiconductor devices are mounted, wherein the printed circuit board comprises: a first signal pad array longitudinally formed in a row on the first side surface, the first signal pad array including a plurality of signal pads; a second signal pad array longitudinally formed in a row on the second side surface which is opposite to the first surface, the second signal pad array being arranged in parallel with the first signal pad array and including a plurality of signal pads; and a third signal pad array longitudinally formed on a bottom surface of the printed circuit board, the bottom surface being disposed between and perpendicular to the first and second side surfaces, wherein the third signal pad array includes a plurality of signal pads which are separated by a plurality of notches which are formed at the bottom surface of the printed circuit board and have a predetermined distance between adjacent ones of the notches.