A magnetics assembly (100) including a transformer (1) made of litz wire. The transformer includes a toroid core (2) and a bundle of wires (3) winding around the toroid core. The bundle of wires includes first to eighth wires, and has a central portion with all eight wires twisted together and winding around the toroid core. First and second ends of the bundle of wires oppositely extend out from the toroidal core. The ends of the first to eighth wires are connected to form a primary and a secondary coils of the transformer, wherein the second ends of the first wire and the second wire, and the first ends of the third wire and the fourth wire are sorted out to form central taps (35, 36) of the primary and secondary coils, respectively.