As mentioned previously, the WE-DD series is available in 7x7mm and 12x12mm, with a straight-pin layout, and in the size 12x12mm with a crossed layout. The parts with a crossed layout have a higher leakage inductance due to the winding structure, where the straight-pin layouts have a lower leakage. The need of low or high leakage is defined by the IC used in the SEPIC convterter. It is recommended to follow the winding layout suggested on the reference design of the IC manufacturer.