Patent ID: 8787022

Claim:
A semiconductor storage device comprising: a printed circuit board mounted with, on one surface, respectively via a plurality of bumps, a plurality of first nonvolatile semiconductor memories and a controller that controls reading of data from and writing of data in the first nonvolatile semiconductor memories; a housing that is formed of a conductive material and houses the printed circuit board; and a first heat radiation member that is interposed between a surface of the housing opposed to one surface of the printed circuit board and the controller and first nonvolatile semiconductor memories and thermally connects the controller and first nonvolatile semiconductor memories and the housing, wherein coupling capacitance in a state in which the first heat radiation member is arranged between a first capacitor formed by the surface of the housing opposed to one surface of the printed circuit board and the printed circuit board is smaller than coupling capacitance in a state in which an integrally formed object having a relative dielectric constant of 5.8 is arranged between the first capacitor to cover a first radiating region containing the controller and the first nonvolatile semiconductor memories.