Transformer of enhance common-mode rejection ratio

A transformer of enhanced common-mode rejection ratio, comprising:

• an iron core comprising a first flange, a second flange, and a central column sandwiched between the first and second flanges, where the central column has a first side face and a second side face;
• and
• a plurality of coils comprising a first coil and a second coil wound around the central column for a plurality of layers along a direction from the first flange towards the second flange;
• wherein, within a first layer and along the first side face of the central column, there are sequentially arranged at least a first round of the first coil, a second round of the first coil, a first round of the second coil, a third round of the first coil, a second round of the second coil, a first gap, a third round of the second coil, a fourth round of the first coil, and a plurality of fifth rounds of the first coil;
• within the first layer and along the second side face of the central column, there are sequentially arranged a plurality of sixth rounds of the first coil, a seventh round of the first coil, a fourth round of the second coil, a second gap, a fifth round of the second coil, an eighth round of the first coil, and a plurality of ninth rounds of the first coil;
• and
• within a second layer surrounding the first layer, there are a plurality of sixth rounds of the second coil.