An electric transformer comprising a coil made of at least one winding (42), the winding (42) being made of a wire comprising a first section (51), a second section (52) and a middle section (55) between the first and the second sections, the first section forming a first spiral around an axis (Z) and the second section forming a second spiral around the axis, the first and second spirals being located in two separate planes (P1, P2) perpendicular to the axis, an inner end (53, 54) of the first spiral, respectively the second spiral, located near the axis being near the middle section (55) of the winding and an outer end (58, 57) of the first spiral, respectively the second spiral, located away from the axis being near a free end of the winding, the first spiral and the second spiral turning around the axis in opposite directions (F1, F2).