Isolated partial power converter

1. An Input-Series-Output-Parallel (ISOP)-type partial power converter circuit comprising:

an isolated, unregulated DC-to-DC converter configured to generate a first output voltage at a first output voltage node, the unregulated DC-to-DC converter comprising a resonant converter operating around a resonant frequency and 0.5 duty cycle; and

a regulated DC-to-DC converter coupled with the unregulated DC-to-DC converter and configured to generate a second output voltage at a second output voltage node, the regulated DC-to-DC converter comprising a resonant forward-flyback converter configuration;

wherein the first output voltage node is coupled to the second output voltage node.

2. The ISOP-type partial power converter circuit of claim 1 , wherein the regulated DC-to-DC converter comprises a half-bridge converter.

3. The ISOP-type partial power converter circuit of claim 2 , wherein the half-bridge converter is coupled in series with a clamping capacitor.

4. The ISOP-type partial power converter circuit of claim 1 , wherein the regulated DC-to-DC converter comprises a transformer having a primary winding and a secondary winding, the regulated DC-to-DC converter further comprising an inductor coupled to the secondary winding and a full-bridge rectifier coupled to the secondary winding through the inductor and a resonance capacitor.

5. The ISOP-type partial power converter circuit of claim 4 , wherein the regulated DC-to-DC converter further comprises:

a first capacitor coupled to the second output voltage node and the secondary winding of the transformer; and

a second capacitor coupled to the secondary winding of the transformer and a ground.

6. The ISOP-type partial power converter circuit of claim 1 , wherein the unregulated DC-to-DC converter is referenced to ground by coupling an input to the unregulated DC-to-DC converter to a circuit ground node.

7. The ISOP-type partial power converter circuit of claim 6 , wherein the regulated DC-to-DC converter further comprises a half-bridge converter coupled to a primary winding of a transformer and to a second input of the unregulated DC-to-DC converter.

8. The ISOP-type partial power converter circuit of claim 1 , wherein the regulated DC-to-DC converter further comprises:

a transformer having a primary winding and a secondary winding, the secondary winding coupled to both a positive output node of the regulated DC-to-DC converter and a flyback output node of the regulated DC-to-DC converter.

9. A partial power converter system comprising:

an isolated, unregulated DC-to-DC converter configured to generate a first output voltage at a first output voltage node, the unregulated DC-to-DC converter comprising a resonant converter operating around a resonant frequency and 0.5 duty cycle; and

a regulated DC-to-DC converter coupled with the unregulated DC-to-DC converter and a power supply node, the regulated DC-to-DC converter being configured to generate a second output voltage at a second output voltage node, the regulated DC-to-DC converter comprising a resonant forward-flyback converter configuration;

wherein the first output voltage node is coupled to a load in parallel with a flyback node of the regulated DC-to-DC converter.

10. The partial power converter system of claim 9 , wherein the regulated DC-to-DC converter comprises a half-bridge converter coupled in series with a clamping capacitor.

11. The partial power converter system of claim 9 , wherein the regulated DC-to-DC converter comprises:

a transformer having primary and secondary windings; and

a half-bridge converter coupled between the second output voltage node and a ground, the secondary windings of the transformer being coupled to a midpoint of the half-bridge converter.

12. The partial power converter system of claim 11 , wherein the regulated DC-to-DC converter further comprises:

a first capacitor coupled to the second output voltage node and the secondary windings of the transformer; and

a second capacitor coupled to the secondary windings of the transformer and a ground.

13. The partial power converter system of claim 9 , wherein the unregulated DC-to-DC converter is referenced to ground by coupling an input to the unregulated DC-to-DC converter to a circuit ground node.

14. The partial power converter system of claim 9 , wherein the regulated DC-to-DC converter comprises a transformer having a primary winding and a secondary winding, the regulated DC-to-DC converter further comprising an inductor coupled to the secondary winding and a full-bridge rectifier coupled to the secondary winding through the inductor and a resonance capacitor.

15. A method for operation of an Input-Series-Output-Parallel (ISOP)-type power converter circuit, the method comprising:

generating a DC power supply voltage;

generating an unregulated DC voltage from the DC power supply voltage with an isolated, unregulated DC-to-DC converter comprising a resonant converter operating around a resonant frequency and 0.5 duty cycle;

generating a regulated DC voltage from the DC power supply voltage with a regulated DC-to-DC converter coupled in parallel with the unregulated DC-to-DC converter and having a resonant forward-flyback converter configuration; and

coupling the unregulated DC voltage to the regulated DC voltage.

16. The method of claim 15 , wherein generating the unregulated DC voltage and the regulated DC voltage comprises applying the DC power supply voltage across an input capacitor, a clamping capacitor, and a series pair of transistors.

17. The method of claim 15 , wherein generating the regulated DC voltage comprises:

transmitting an AC voltage over a transformer wherein a secondary AC voltage is 180° out of phase with a primary AC voltage; and

converting the secondary AC voltage to the regulated DC voltage.

18. The method of claim 15 , wherein the regulated DC-to-DC converter comprises a half-bridge converter.

19. The method of claim 18 , wherein the half-bridge converter is coupled in series with a clamping capacitor.

20. The method of claim 15 , wherein the regulated DC-to-DC converter comprises a transformer having a primary winding and a secondary winding, the regulated DC-to-DC converter further comprising an inductor coupled to the secondary winding and a full-bridge rectifier coupled to the secondary winding through the inductor and a resonance capacitor.