The heat transfer portion 21, the graphite sheet 4, the heat conductive portion 5, and the electronic component 7 form a laminated body in which they are closely/coherently laminated. The laminated bodies are layered/stacked in the vertical direction. The Z direction in each figure is also a stacking direction. The heat transfer portion 21 is an external heat dissipater that forms a heat path to the fins 22. The heat transfer portion 21 is a section in which the heat generated by the electronic component 7 is transmitted via the graphite sheet 4 and the heat conductive portion 5.

The heat transferred to the heat transfer portion 21 is conducted to the fins 22 and is released from the surface of each fin 22 to the outside atmosphere. As a result, the heat of the electronic component 7 is released to the outside of the cooling device 1, and the electronic component 7 can be cooled. The heat sink 2 is made of a metal material, for example, an aluminum die-cast.

The electronic component 7 is a heat-generating component that generates heat by itself. The electronic component 7 includes, for example, a resistor, a semiconductor chip having a semiconductor integrated circuit, and the like. The electronic component 7 is connected to the circuit board 8 via a bonding member. The electronic component 7 transmits and receives electric power, signals, and the like to and from the circuit board 8.