A Dual Winding Inductor is a component comprised of two exactly identical windings, sharing the same core and magnetic flux path, creating optimum coupling in a SEPIC converter circuit. This great coupling factor is what gives Dual Winding Inductors the ability to offer many advantages, technical and economical respectively. Through tight winding coupling, the input ripple current is virtually cancelled and the inductor size reduced to almost half of its original. In addition as a direct result, other components in the SEPIC circuit, such as the EMI filter and the input capacitor, may be designed in lower platforms. The smaller inductor size also yields higher efficiencies from lower winding DC resistances and copper losses. With the usage of a single Dual Winding Inductor the parts count of the bill of materials is lowered and the board spacing reduced. Smaller boards, lower part counts and reduced size components offer cost savings.