Disclosed herein is an apparatus that includes a substrate having first and second surfaces opposite to each other, a first coil pattern formed on the first surface of the substrate, and a second coil pattern formed on the second surface of the substrate. The first coil pattern includes first and second lines, and the second coil pattern includes third and fourth lines. The first line is greater in a number of turn than the second line, and the third line is greater in a number of turn than the fourth line. The first line is connected to the fourth line, and the third line is connected to the second line.