Electronic device

An electronic device installable on a vehicle, the electronic device comprising:

• a heat-receiving block being heat conductive and having a first main surface to which an electronic component is attachable;
• a heat transfer member attached to a second main surface of the heat-receiving block, the second main surface being opposite to the first main surface, the heat transfer member extending away from the second main surface to transfer, in a direction away from the second main surface, heat transferred from the electronic component through the heat-receiving block;
• and
• one or more fins attached to the heat transfer member to dissipate heat transferred from the electronic component through the heat-receiving block and the heat transfer member into ambient air, at least one fin of the one or more fins having at least one ventilation hole to guide the ambient air in the direction away from the second main surface,
• wherein the at least one fin of the one or more fins having the at least one ventilation hole has a first region including a middle of the at least one fin having the at least one ventilation hole in a travel direction or a width direction of the vehicle and second regions located across the first region and having a same area as the first region, and a ratio of an opening area of the at least one ventilation hole is higher in the first region than in the second regions, ambient air receiving heat transferred from the at least one fin thereby moves from the second regions to the first region and flows in the direction away from the second main surface of the heat-receiving block through the at least one ventilation hole in the first region, and convection of air enables cooling of the electronic component also when the vehicle is stopped.