Abstract: DC-DC converter according to an exemplary embodiment of the inventive concept includes: a first transformation unit including a first primary winding and a second primary winding and configured to convert a voltage applied to the first primary winding or the second primary winding and output the converted voltage to a first secondary winding; a second transformation unit including a third primary winding and a fourth primary winding and configured to convert a voltage applied to the third primary winding or the fourth primary winding and output the converted voltage to a second secondary winding, wherein the first primary winding and the third primary winding are connected to each other in series, and the second primary winding and the fourth primary winding are connected to each other in series.