Clamp circuits for power converters

A power converter, comprising:

• an input port configured to receive a source of power;
• an output port configured to provide output power;
• a bridge circuit operatively coupled to the input port, the bridge circuit comprising:
• a first transistor coupled in series with a second transistor;
• a third transistor coupled in series with a fourth transistor;
• a first clamp diode coupled in series with a second clamp diode, wherein the first and second clamp diodes are coupled in parallel with the first and second transistors;
• a first clamp capacitor coupled between the first and second clamp diodes;
• a third clamp diode coupled in series with a fourth clamp diode, wherein the third and fourth clamp diodes are coupled in parallel with the third and fourth transistors;
• a second clamp capacitor coupled between the third and fourth clamp diodes;
• and
• a first resonant inductor coupled between the first and second a first resonant inductor coupled between the first and second transistors;
• and
• a second resonant inductor coupled between the third and fourth transistors;
• a transformer operatively coupled to the bridge circuit;
• a current rectifying circuit operatively coupled to the transformer and the output port;
• an output inductor coupled between the transformer and the output port;
• and
• a transformer leakage inductor coupled between the first resonant inductor and the transformer;
• wherein the first and second resonant inductors are configured to produce the same inductance values.

An electronic system comprising:

• at least one processor;
• at least on memory device operatively coupled to the processor;
• and
• at least one power converter electrically coupled to the processor and the memory unit, the power converter comprising:
• a bridge circuit comprising:
• a first transistor coupled in series with a second transistor;
• a third transistor coupled in series with a fourth transistor;
• a first clamp rectifier coupled in series with a second clamp rectifier, wherein the first and second clamp rectifiers are coupled in parallel with the first and second transistors;
• a first clamp capacitor coupled between the first and second clamp rectifiers, the first clamp capacitor operative to reduce power loss in the first and second clamp rectifiers;
• and
• a first resonant inductor coupled between the first and second transistors;
• a transformer operatively coupled to the bridge circuit;
• and
• a current rectifying circuit operatively coupled to the transformer.

A method comprising:

• receiving an input DC voltage at a resonant inductor, the resonant inductor coupled to a transformer and a clamp capacitor;
• generating control signals for a first switch and a second switch coupled to the transformer;
• storing energy in the resonant inductor from the input DC voltage when the control signals turn on both of the first and second switches;
• and
• releasing energy from the resonant inductor through the transformer when the control signals turn on only one of the first and second switches;
• wherein the clamp capacitor allows part of a current to flow to a third switch or a fourth switch to reduce power loss in one or more clamp rectifiers.