Abstract: A transformer of a switching power-supply circuit is placed and mounted nearly in the middle area of a circuit board. The transformer is of a low-profile type, and a broad and flat upper surface of the transformer functions as a suction surface for a suction nozzle. When a surface-mount type switching power-supply unit is mounted in a mother board, firstly, the upper surface of the above transformer is held by the suction nozzle, the surface-mount type switching power-supply unit is transferred to a target mounting area on the mother board by the suction nozzle, and the surface-mount type switching power-supply unit is surface mounted in the mother board. Because it is not required to provide a nozzle suction surface for the suction nozzle's exclusive use, transfer molding is not needed, and accordingly a low-profile and low-cost surface-mount type switching power-supply unit can be facilitated.

Abstract: A transformer of a switching power-supply circuit is placed and mounted nearly in the middle area of a circuit board. The transformer is of a low-profile type, and a broad and flat upper surface of the transformer functions as a suction surface for a suction nozzle. When a surface-mount type switching power-supply unit is mounted in a mother board, firstly, the upper surface of the above transformer is held by the suction nozzle, the surface-mount type switching power-supply unit is transferred to a target mounting area on the mother board by the suction nozzle, and the surface-mount type switching power-supply unit is surface mounted in the mother board. Because it is not required to provide a nozzle suction surface for the suction nozzle's exclusive use, transfer molding is not needed, and accordingly a low-profile and low-cost surface-mount type switching power-supply unit can be facilitated.