Patent ID: 8823177

Claim:
A semiconductor device comprising: a semiconductor chip having a plurality of electrodes including a plurality of first electrode pairs for a plurality of differential pairs for transmitting a differential signal; and a wiring substrate having a front surface over which the semiconductor chip is mounted, a back surface opposite to the front surface, a side surface intersecting the front surface and the back surface, and a plurality of external terminals electrically connected to the semiconductor chip and arrayed in a matrix pattern in the back surface, wherein the external terminals include: a plurality of first external terminal pairs electrically connected to the first electrode pairs of the semiconductor chip; and a plurality of second external terminals electrically connected to a plurality of second electrodes different from the first electrode pairs of the semiconductor chip; wherein the first external terminal pairs include: a third external terminal pair located in an outermost periphery of the matrix pattern in the back surface of the wiring substrate; and a fourth external terminal pair located inward of the outermost periphery of the matrix pattern and in a row next to the outermost periphery in the back surface of the wiring substrate, wherein the outermost periphery of the matrix pattern includes: a first region in which the external terminals are arranged at a first spacing; and a second region in which the external terminals are arranged at a second spacing larger than the first spacing, wherein the second region lies between the fourth external terminal pair and the side surface of the wiring substrate.