High efficiency power converter

A power converter, comprising:

• a resonant switched capacitor converter having one or more resonant switched capacitor stages, each resonant switched capacitor stage further comprising:
• a ladder of four switching devices coupled across an input of the resonant switched capacitor stage;
• a resonant tank circuit including a flying capacitor and a resonant inductance coupled between a junction of a first and a second switching device of the ladder and a junction of a third and fourth switching device of the ladder;
• and
• an output terminal located at a junction of the second and third switching devices of the ladder;
• wherein the resonant switched capacitor converter receives an input voltage and input current from a power source and produces an intermediate voltage that is a fraction of the input voltage and an intermediate current that is a corresponding multiple of the input current;
• a buck regulator that receives the intermediate voltage and the intermediate current and produces an output voltage and an output current, wherein the output voltage is less than the intermediate voltage;
• and
• controller circuitry that regulates a switching frequency of the resonant switched capacitor converter to achieve soft switching.

A resonant switched capacitor converter having one or more resonant switched capacitor stages, each resonant switched capacitor stage comprising:

• a ladder of four switching devices coupled across an input of the resonant switched capacitor stage;
• a resonant tank circuit including a flying capacitor and a resonant inductance coupled between a junction of a first and a second switching device of the ladder and a junction of a third and fourth switching device of the ladder;
• an output terminal located at a junction of the second and third switching devices of the ladder;
• and
• controller circuitry that regulates a switching frequency of the resonant switched capacitor converter to achieve soft switching.