Claims
- 1. For use with an asymmetrical half-bridge power converter having a primary switching circuit coupled to a primary winding of a transformer and a rectifier coupled to a secondary winding of said transformer, a reverse recovery circuit, comprising:
an inductor configured to reduce current spikes in said primary switching circuit caused by a reverse recovery phenomenon associated with said rectifier; and a diode, coupled to said inductor, configured to clamp a voltage across said rectifier.
- 2. The circuit as recited in claim 1 further comprising an auxiliary winding, coupled to said inductor, configured to transfer a portion of energy in said inductor to said secondary winding.
- 3. The circuit as recited in claim 2 wherein said inductor and said auxiliary winding are series-coupled to said primary winding.
- 4. The circuit as recited in claim 2 wherein said diode is coupled to a node between said auxiliary winding and said primary winding.
- 5. The circuit as recited in claim 4 further comprising a second diode coupled to said node.
- 6. The circuit as recited in claim 1 wherein said power converter further comprises a controller configured to control conduction intervals of a power switch of said primary switching circuit.
- 7. The circuit as recited in claim 6 wherein said controller is configured to monitor an output voltage of said power converter and to operate said power switch in response thereto.
- 8. For use with an asymmetrical half-bridge power converter having a primary switching circuit coupled to a primary winding of a transformer and a rectifier coupled to a secondary winding of said transformer, a method for reducing losses associated with said power converter, comprising:
employing an inductor to reduce current spikes in said primary switching circuit caused by a reverse recovery phenomenon associated with said rectifier; and employing a diode, coupled to said inductor, to clamp a voltage across said rectifier.
- 9. The method as recited in claim 8 further comprising employing an auxiliary winding, coupled to said inductor, to transfer a portion of energy in said inductor to said secondary winding.
- 10. The method as recited in claim 9 wherein said inductor and said auxiliary winding are series-coupled to said primary winding.
- 11. The method as recited in claim 9 wherein said diode is coupled to a node between said auxiliary winding and said primary winding.
- 12. The method as recited in claim 11 further comprising a second diode coupled to said node.
- 13. The method as recited in claim 8 further comprising controlling conduction intervals of a power switch of said primary switching circuit.
- 14. The method as recited in claim 13 wherein said controlling comprises monitoring an output voltage of said power converter and to operating said power switch in response thereto.
- 15. An asymmetrical half-bridge power converter, comprising:
a transformer having a primary winding and a secondary winding; a power switching circuit coupled to said primary winding; a rectifier coupled to said secondary winding; and a reverse recovery circuit, including:
an inductor that reduces current spikes in said primary switching circuit caused by a reverse recovery phenomenon associated with said rectifier, and a diode, coupled to said inductor, that clamps a voltage across said rectifier.
- 16. The power converter as recited in claim 15 wherein said reverse recovery circuit further comprises an auxiliary winding, coupled to said inductor, that transfers a portion of energy in said inductor to said secondary winding.
- 17. The power converter as recited in claim 16 wherein said inductor and said auxiliary winding are series-coupled to said primary winding.
- 18. The power converter as recited in claim 16 wherein said diode is coupled to a node between said auxiliary winding and said primary winding.
- 19. The power converter as recited in claim 18 wherein said reverse recovery circuit further comprises a second diode coupled to said node.
- 20. The power converter as recited in claim 15 further comprising a controller that controls conduction intervals of a power switch of said primary switching circuit.
- 21. The power converter as recited in claim 20 wherein said controller monitors an output voltage of said power converter and to operate said power switch in response thereto.
CROSS-REFERENCE TO RELATED APPLICATION
[0001] This application is related to U.S. patent application Attorney Docket No. FRAIDLIN 22-3-2-9, Ser. No. 09/602,416, entitled “Circuit for Reducing Losses Associated with a Power Converter and Method of Operation Thereof,” by Simon Fraidlin, et al., filed on Jun. 23, 2000, which is incorporated herein by reference.