The present invention provides a splitter including a seat, a first inner core, a second inner core, a first coil, an outer core and a second coil. The seat has a bobbin, and the first coil is wound on the bobbin. The first inner core and the second inner core, disposed on the bobbin, are assembled with each other to cover the bobbin. The outer core and the first inner core are assembled with each other. The second coil is disposed between the outer core and the first inner core.