Abstract: A printed circuit board (10) including a layered transformer (1) has a stack of layers of a first magnetic layer (2), a first transformer coil (4), an insulating body (7), a second transformer coil (5) and a second magnetic layer (3), wherein each of the transformer coils (4, 5) is embodied as a two-dimensional pattern of conductive tracks. The insulating body may comprise one of more channels (8, 18, 28) containing a magnetic material. Instead of one printed circuit board (10), the transformer (1) may be embodied in two printed circuit boards (60) as well, each comprising a magnetic layer (2) and a transformer coil (4). Said printed circuit boards may be included in a charger device (71) and a user device (72).

Abstract: A printed circuit board (10) including a layered transformer (1) has a stack of layers of a first magnetic layer (2), a first transformer coil (4), an insulating body (7), a second transformer coil (5) and a second magnetic layer (3), wherein each of the transformer coils (4,5) is embodied as a two-dimensional pattern of conductive tracks. The insulating body may comprise one of more channels (8,18,28) containing a magnetic material. Instead of one printed circuit board (10), the transformer (1) may be embodied in two printed circuit boards (60) as well, each comprising a magnetic layer (2) and a transformer coil (4). Said printed circuit boards may be included in a charger device (71) and a user device (72).

Abstract: A transformer comprising a plurality of conductive screening foils located between the core and the windings and between the primary and secondary windings. In order to prevent eddy current losses in the screening foils, at least the first screening foil is made of a soft-magnetic material.