Printed circuit board

A printed circuit board, comprising:

• a board body portion comprising a plurality of core boards and a plurality of dielectric layers that are parallel to each other and laminated alternately, wherein the plurality of core boards comprise a plurality of conductor layers, and the plurality of conductor layers comprise a differential signal transmission layer located on a surface layer of the board body portion and a differential signal line out layer located on an inner layer of the board body portion;
• two opposite differential signal holes located on the board body portion, wherein the two differential signal holes are passed sequentially from the differential signal transmission layer to the differential signal line out layer through at least a portion of the core boards and connect the differential signal transmission layer to the differential signal line out layer;
• two slotted conductive posts located between the two differential signal holes, wherein the two slotted conductive posts are adjacent to the two differential signal holes respectively, and the two slotted conductive posts are extended from the differential signal transmission layer to the differential signal line out layer;
• and
• two first signal hole pads provided on the surface layer of the board body portion and connected to the two differential signal holes respectively, and two ball grid array (BGA) pads connected to the two first signal hole pads respectively,
• wherein each of the first signal hole pads comprises a main body portion connected to the BGA pad and an extension portion connected to the main body portion, an end of each differential signal hole is passed through the main body portion and connected to the main body portion, and an end of the slotted conductive post adjacent to the differential signal transmission layer is connected to the extension portion.