Abstract: The converter comprises a transformer having two primary windings; a voltage source having one of its terminals connected to the center tap; and two switches connected in series between the other terminal of the voltage source and a respective one of the primary windings, the switches having stray capacitances that impose a transition time between one of the switches switching OFF and the other switch switching ON. The transformer comprises a magnetic circuit having a gap, and each primary winding has a number of turns that is determined essentially as a function of the level of losses acceptable within the magnetic circuit, the size of the gap then being adjusted, taking account of the number of turns and the operating frequency, in such a manner as to reduce the magnetizing inductance of the transformer to a value such that said transition time is less than a given threshold corresponding to tolerances of the form factor.