Multiphase converter with zero voltage switching
View Patent ↗A multiphase DC-to-DC converter includes at least two phase circuits each having upper and lower power switches and a front-end inductor that is operative for forming a resonant tank circuit with the phase circuits to ensure zero voltage switching and minimizing power losses.
1. A multiphase DC-to-DC converter comprising:
a plurality of phase circuits, each having an upper power switch coupled to a following lower power switch;
an input inductor coupled to an input voltage source, operative for each of said plurality of phase circuits, forming a resonant tank circuit with each of said phase circuits, and minimizing power losses within said converter;
a controller configured to drive each of said phase circuits; and
a feedback circuit configured to provide feedback from each of said phase circuits to said controller to ensure zero voltage switching of said phase circuits.
2. A multiphase DC-to-DC converter according to claim 1 wherein said controller is operative with each of said phase circuits for detecting zero volt crossings therein.
3. A multiphase DC-to-DC converter according to claim 2 wherein said controller comprises a pulse-width modulation controller.
4. A multiphase DC-to-DC converter according to claim 1 wherein said resonant tank circuit is created to achieve zero voltage across said power switches.
5. A multiphase DC-to-DC converter according to claim 1 wherein said upper and lower power switches comprise field effect transistors.
6. A multiphase DC-to-DC converter according to claim 1 and further comprising an output capacitor operative with a voltage output from said phase circuits.
7. A multiphase DC-to-DC converter according to claim 1 , and further comprising an output inductor operative within each phase circuit.
8. A multiphase DC-to-DC converter comprising:
more than two phase circuits, each having an upper power switch coupled to a following lower power switch, and having a capacitor operative with at least each upper power switch; and
an input inductor coupled to an input voltage source, and operative for forming a resonant tank circuit with said upper power switches and capacitors for each of said phase circuits to ensure zero voltage switching and to minimize power losses.
9. A multiphase DC-to-DC converter according to claim 8 wherein an upper capacitor is connected in parallel to a respective upper power switch.
10. A multiphase DC-to-DC converter according to claim 8 and further comprising a diode operative with each upper power switch to enhance zero voltage switching.
11. A multiphase DC-to-DC converter according to claim 8 and further comprising a diode operative with each lower power switch to enhance zero voltage switches.
12. A multiphase DC-to-DC converter according to claim 8 and further comprising a lower capacitor operative with each lower power switch.
13. A multiphase DC-to-DC converter according to claim 8 and further comprising a controller operative with a phase circuit for detecting a zero volt crossing.
14. A multiphase DC-to-DC converter according to claim 13 wherein said controller comprises a pulse-width modulation controller.
15. A multiphase DC-to-DC converter according to claim 8 wherein said resonant tank circuit is created that achieves zero voltage across said power switches.
16. A multiphase DC-to-DC converter according to claim 8 wherein said upper and lower power switches comprise field effect transistors.
17. A multiphase DC-to-DC converter according to claim 8 and further comprising a feedback signal processing circuit operative with each phase circuit.
18. A multiphase DC-to-DC converter according to claim 8 and further comprising an output capacitor operative with a voltage output from said phase circuits.
19. A multiphase DC-to-DC converter according to claim 8 , and further comprising an output inductor operative with phase circuits.
20. A method for regulating a multiphase DC-to-DC converter comprising:
forming a resonant tank circuit with each of a plurality of phase circuits using a front end inductor;
switching an upper power switch and a lower power switch coupled to and following said upper power switch in each of said phase circuits; and
maintaining said switching activity at zero volts via feedback to ensure zero voltage switching and to minimize power losses.
21. A method according to claim 20 wherein said method further comprises detecting a zero volt crossing.
22. A method according to claim 20 wherein said method further comprises forming a resonant tank circuit with capacitors operative with said power switches.
23. A method according to claim 20 wherein said method further comprises forming a resonant tank circuit with diodes operative with said power switches.
24. A multiphase DC-to-DC converter according to claim 8 further comprising:
a control circuit coupled configured to control each of said phase circuits; and
a feedback circuit configured coupled between each of said phase circuits and said control circuit.
25. A multiphase DC-to-DC converter according to claim 1 wherein said upper power switch is coupled directly to said lower power switch.
26. A multiphase DC-to-DC converter according to claim 1 wherein said input inductor is common to said plurality of phase circuits.
27. A multiphase DC-to-DC converter comprising:
an input voltage source;
an input inductor coupled to said input voltage source;
a plurality of upper power switches coupled to said input inductor, wherein each of said upper powers switches is an upper power switch for one of a plurality of phases;
a plurality of lower power switches, wherein each of said lower power switches is coupled to a corresponding one of said upper power switches for each of said plurality of phases; and
a controller configured to drive each of said upper and lower power switches.