TRANSFORMER AND CIRCUIT BOARD COMPRISING SAME

The present invention relates to a transformer and a circuit board comprising same. One embodiment of the transformer according to the present invention comprises: a core part comprising a core lower portion and a core upper portion disposed on the core lower portion; and a coil part which comprises a first coil and a second coil and of which at least a portion is disposed in the core part, wherein the core lower portion has a closed region which overlaps the core upper portion in a first direction from the core lower portion toward the core upper portion, and an open region which extends from the closed region in a second direction perpendicular to the first direction and which is exposed to the outside of the closed area.