Switched-capacitor converter with multi-tapped autotransformer

An apparatus comprising:

• a switched-capacitor converter including multiple capacitors;
• a transformer including a first primary winding and a second primary winding, the multiple capacitors of the switched-capacitor converter controllably switched in circuit paths including the first primary winding and the second primary winding;
• an output stage coupled to receive energy from a combination of the first primary winding and the second primary winding of the transformer, the output stage operable to produce an output voltage to power a load;
• and
• wherein the first primary winding and the second primary winding are connected in series through a secondary winding of the transformer.

A method comprising:

• receiving energy from an input voltage source;
• controllably switching multiple capacitor circuit paths to convey the energy from the input voltage source to a first primary winding and a second primary winding of a multi-tapped autotransformer, the multi-tapped autotransformer operable to convey the energy to an output stage;
• at the output stage, via the energy received from the multi-tapped autotransformer, producing an output voltage to power a load;
• and
• wherein the first primary winding, the second primary winding, and a secondary winding of the multi-tapped autotransformer are connected in series.

An apparatus comprising:

• a switched-capacitor converter including multiple capacitors;
• a multi-tapped autotransformer including a first primary winding and a second primary winding, the multiple capacitors of the switched-capacitor converter controllably switched in circuit paths including the first primary winding and the second primary winding;
• and
• an output stage coupled to receive energy from a combination of the first primary winding and the second primary winding of the multi-tapped autotransformer, the output stage operable to produce an output voltage to power a load;
• wherein the output stage includes a secondary winding magnetically coupled to the first primary winding and the second primary winding, the secondary winding operable to produce the output voltage;
• wherein the multiple capacitors include a first capacitor and a second capacitor, the apparatus further comprising:
• a first switch, the first switch operable to selectively couple a first node of the first capacitor to a first transformer node connecting the first primary winding and the secondary winding, a second node of the first capacitor coupled to the second primary winding;
• and
• a second switch, the second switch operable to selectively couple a first node of the second capacitor to a second transformer node connecting the second primary winding and the secondary winding, a second node of the second capacitor coupled to the first primary winding;
• and
• a controller operable to control activation of the first switch and the second switch at different times.