VEHICLE-MOUNTED POWER SUPPLY APPARATUS AND VEHICLE

In accordance with an embodiment an apparatus, includes: a power conversion circuit having: a power port configured to receive power from an external power supply, a first direct current port configured to output a first direct current, a second direct current port configured to output a second direct current, wherein a voltage of the second direct current port is configured to be higher than a voltage of the first direct current port, an upper-layer printed circuit board (PCB) electrically connected to the second direct current port, and a lower-layer PCB electrically connected to the first direct current port and to the power port; a bottom housing; and a heat sink, wherein the lower-layer PCB, the upper-layer PCB, and the heat sink are sequentially stacked in and fastened to the bottom housing.