Multi-resonant converter power supply
In one embodiment, an apparatus includes a first stage comprising a first active switch, a first resonant inductor, and a resonant capacitor and a second stage comprising a second active switch, a second resonant inductor, and a filter capacitor. The first and second stages form a non-isolated multi-resonant converter for converting a DC input voltage to a DC output voltage.
1. An apparatus comprising:
a first stage comprising a first active switch, a first resonant inductor, and a resonant capacitor; and
a second stage comprising a second active switch, a second resonant inductor, and a filter capacitor;
wherein said first and second stages form a non-isolated multi-resonant converter for converting a DC input voltage to a DC output voltage and the apparatus comprises an input isolation stage.
2. The apparatus of claim 1 wherein the non-isolated multi-resonant converter comprises a step-down voltage converter.
3. The apparatus of claim 1 wherein the non-isolated multi-resonant converter comprises a step-up voltage converter.
4. The apparatus of claim 1 wherein at least one of said stages comprises a synchronous rectifier.
5. The apparatus of claim 1 wherein each of said stages comprises a synchronous rectifier.
6. The apparatus of claim 1 wherein said first and second resonant inductors operate with currents in discontinuous mode and wherein a voltage at the resonant capacitor discharges to zero on each of a plurality of cycles.
7. The apparatus of claim 1 wherein said first and second resonant inductors operate with currents in continuous mode and wherein a voltage at the resonant capacitor discharges other than zero on each of a plurality of cycles.
8. The apparatus of claim 1 wherein said first stage and said second stage operate in discontinuous current mode with switch zero-current turn-on.
9. The apparatus of claim 1 wherein the apparatus is operable to use frequency modulation to regulate output voltage and current.
10. The apparatus of claim 1 wherein said first stage is configured to use pulse width modulation to regulate a charge stored on the resonant capacitor to regulate output voltage and current.
11. The apparatus of claim 1 wherein said second resonant inductor comprises a tapped inductor.
12. An apparatus comprising:
a first stage comprising a first active switch, a first resonant inductor, and a resonant capacitor; and
a second stage comprising a second active switch, a second resonant inductor, and a filter capacitor;
wherein said first and second stages form a non-isolated multi-resonant converter for converting a DC input voltage to a DC output voltage and the apparatus comprises a power factor correction stage.
13. The apparatus of claim 12 wherein the non-isolated multi-resonant converter comprises a step-down voltage converter.
14. The apparatus of claim 12 wherein the non-isolated multi-resonant converter comprises a step-up voltage converter.
15. An apparatus comprising:
a card for insertion into a network device, the card comprising a point-of-load power supply comprising:
a first stage comprising a first switch, a first inductor, and a resonant capacitor; and
a second stage comprising a second switch, a second inductor, and a filter capacitor;
wherein said first stage comprises a power regulation resonant stage and said second stage comprises a voltage converter resonant stage to form a non-isolated multi-resonant converter and the apparatus comprises an input isolation stage.
16. The apparatus of 14 wherein the point-of-load power supply eliminates a need for an intermediate bus converter on the card.
17. The apparatus of claim 15 wherein at least one of said stages comprises a synchronous rectifier.
18. The apparatus of claim 15 wherein said second inductor comprises a tapped resonant inductor.
19. The apparatus of claim 15 wherein said first stage is configured to use pulse width modulation or frequency modulation to regulate output voltage and current.
20. A point-of-load power supply comprising:
a first stage comprising a first active switch, a resonant inductor, and a resonant capacitor; and
a second stage comprising a second active switch, a tapped resonant inductor, and a filter capacitor;
wherein said first stage and said second stage form a non-isolated multi-resonant converter for converting a DC input voltage to a DC output voltage with a step-down voltage conversion or a step-up voltage conversion; and
wherein the point-of-load power supply comprises a power factor correction stage.