In an electronic device, a QFN is surface-mounted on a printed board. The QFN includes a main body containing an IC chip, a reinforcement portion, and multiple terminal portions. The reinforcement portion is exposed from a bottom portion of the main body and mechanically coupled with multiple reinforcement lands on the printed board. The multiple terminal portions are exposed from a peripheral of the main body and electrically coupled with multiple lands on the printed board. In the printed board, the multiple lands are connected with multiple conductive wires. Some of the multiple conductive wires are outside of the surface-mounted area. The others are inside of the surface-mounted area to face the reinforcement lands. This enhances a mounting efficiency in the printed board.