enter link description hereIn a design of a fly back converter the transformer used has 3 windings i.e primary 328uH and secondary and auxiliary windings and the primary winding has 54 turns but in the construction details the primary was split in two i.e 27 windings each.My doubt is should the primary windings have 4 pins on bobbin or just 2. The transformer guy used 3 pins for the primary.I have limited knowledge about transformer so if someone could help it would be great.

Thanks in advances

UCC2863x, High-Power Flyback Controller with Primary-Side Regulation and Peak-Power Mode

In a design of a fly back converter the transformer used has 3 windings i.e. primary 328 μH and secondary and auxiliary windings and the primary winding has 54 turns but in the construction details the primary was split in two i.e. 27 windings each.

My doubt is should the primary windings have 4 pins on bobbin or just 2? The transformer guy used 3 pins for the primary. I have limited knowledge of transformers so if someone could help it would be great.