A higher power package is provided in a smaller package by providing at least first and second magnetics in parallel in first and second transformers. To limit degrading performance associated with circulating current between the two transformers, the transformers are electrically decoupled. In a preferred embodiment, the circuit includes parallel primary and secondary windings of the transformer that are decoupled electrically on an output side. Particularly, diodes are provided in a preheat portion of the circuit so that once the preheat phase is terminated, the diodes prevent current flow in one direction through the preheat portion of the circuit.