Patent ID: 8355254

Claim:
An electronic control unit comprising: a circuit board; a plurality of circuit patterns, which are formed on the circuit board; a plurality of semiconductor devices, each of which is installed to a corresponding one of the plurality of circuit patterns; a plurality of leads, each of which electrically and mechanically connects between the corresponding one of the plurality of circuit patterns and a corresponding one of the plurality of semiconductor devices; and at least one thermal-conduction limiting portion, which is placed between corresponding two of the plurality of circuit patterns and that limits conduction of heat, which is generated from at least one of the plurality of semiconductor devices upon operation thereof, between the corresponding two of the plurality of circuit patterns, wherein the plurality of circuit patterns includes first to fourth circuit patterns, the plurality of semiconductor devices includes first to fourth semiconductor devices, the plurality of leads includes first to fourth leads, the first to fourth semiconductor devices are installed to the first to fourth circuit patterns, respectively, the first to fourth leads electrically and mechanically connect the first to fourth semiconductor devices to the first to fourth circuit patterns, respectively, to form an H-bridge circuit, the first and second semiconductor devices are configured to be energized simultaneously and are placed obliquely with respect to each other on the circuit board, the third and fourth semiconductor devices are configured to be energized simultaneously and are placed obliquely with respect to each other on the circuit board, and the thermal-conduction limiting portion limits conduction of heat, generated by the first to fourth semiconductor devices, between the first to fourth circuit patterns.