High efficiency DC/DC converter and controller

A circuit for use as a DC/DC converter, the circuit comprising:

• a fullbridge subcircuit coupled in parallel to an input, said fullbridge subcircuit including a plurality of power semiconductors arranged in a bridge configuration;
• a high frequency transformer subcircuit coupled to said fullbridge subcircuit;
• a diode bridge subcircuit coupled to said transformer subcircuit;
• a parallel capacitor coupled in parallel to said diode bridge subcircuit;
• a subcircuit for providing reactive current for said power semiconductors for zero voltage switching of said semiconductors;
• wherein
• said parallel capacitor is coupled to an output of said converter;
• said subcircuit for providing reactive current is an inductor coupled in parallel to a transformer in said transformer subcircuit;
• said transformer subcircuit comprises a series inductor coupled in series between said transformer and an input from said full bridge subcircuit;
• wherein said diode bridge subcircuit comprises a first pair of diodes coupled in series and a second pair of diodes coupled in series, said first pair of diodes being coupled in parallel with said second pair of diodes, said transformer subcircuit being coupled to a first connection point between said first pair of diodes and to a second connection point between said second pair of diodes;
• and
• said inductor coupled in parallel to said transformer is coupled between said first connection point and said second connection point.