Integrally-formed coupling inductor and manufacturing method thereof

The invention provides an integrally-formed coupling inductor and a manufacturing method thereof. The integrally-formed coupling inductor comprises a lead frame, a first single-strand coil, a second single-strand coil and a magnetic packaging piece. The lead frame is provided with a first surface and a second surface which are opposite to each other, and the lead frame comprises four pins; the first single-strand coil is arranged on the first surface, and two ends of the first single-strand coil are respectively welded with two of the four pins; the second single-strand coil is arranged on the second surface, and the other two pins of the four pins are welded to the two ends of the second single-strand coil respectively; the magnetic packaging piece wraps the first single-strand coil and the second single-strand coil, and partial sections of the four pins are exposed out of the first single-strand coil and the second single-strand coil. The two single-strand coils are welded to the pins of the different suppo