A semiconductor device includes an insulating layer disposed over a substrate, wherein the insulating layer has a center region. A first winding portion and a second winding portion are electrically connected to the first winding portion, disposed in a first level of the insulating layer and surrounding the center region, wherein each of the first winding portion and the second winding portion comprises a plurality of conductive lines arranged from the inside to the outside. A first extending conductive line and a second extending conductive line partially surround the first extending conductive line, and are disposed in the first level of the insulating layer, wherein the first winding portion and the second winding portion surround the first extending conductive line and the second extending conductive line. A third extending conductive line is disposed in a second level of the insulating layer and surrounding the center region.