TRANSFORMATOR

A transformer (1) includes a bobbin (2) defining primary (21) and secondary (22) winding chambers, a core (4) mounted on said bobbin, as well as primary (31) and a secondary (32) windings wound in the primary (21) and secondary (22) winding chambers. The core (4) is an EFD/EFF ferrite core, and the bobbin (2) includes a cover cap (52) for the secondary winding chamber (22). The bobbin (2) including the cover cap (52) are configured to provide reinforced insulation of the secondary winding (32) with respect to the primary winding (31) and the core (4) to render the transformer (1) SELV-compliant with EN 61347, and compliant with UL 1310.