The present invention relates to a transformer assembly (1) and a process for manufacturing same. The transformer (1) comprises a primary winding (5) wound on a PCB (9) and a secondary winding (7) mounted adjacent to the primary winding. The primary winding comprises a spiral coil, for example of wire or insulated wire, wound on the PCB. Gate drive windings (31, 33) are incorporated in the PCB (9) and there is therefore very close coupling between the primary winding and the gate drive windings. Furthermore, the secondary winding (7) is a center-tapped secondary having two halves. A flux balance winding (13) is provided to connect the two halves of the center-tapped secondary winding (7) and minimize leakage inductance thereby reducing power loss and spiking effects and obviating the need for complex control arrangements.