The present disclosure describes an electronic control unit having a substrate that improves the heat dissipation from one surface of a substrate to another surface of the substrate to improve the connectivity between a substrate and a terminal. The present disclosure also describes an electric power steering device using the electronic control unit.
By forming the vias in the substrate, the vias can help assist the terminal connection portion in the transfer of heat during a soldering process from the first surface side of the substrate to the second surface side. The transfer of heat from one surface of the substrate to another improves the solderability of a terminal in the terminal connection portion to the substrate to provide a better soldered connection between the terminal and the substrate.
Various embodiments in the present disclosure are described with reference to the drawings. In the following embodiments, like features and elements among the embodiments may be referred to by the same reference numerals, and a repeat description of previously described like features and elements may be omitted from the descriptions of the latter embodiments.