Method and apparatus for auto-interleaving synchronization in a multiphase switching power converter

• US 6,965,219 B2
• Filed: 04/25/2003
• Issued: 11/15/2005
• Est. Priority Date: 06/28/2002
• Status: Expired due to Fees

• Current Assignee: Microsemi Corporation (Microchip Technology Incorporated)
• Original Assignee: Microsemi Corporation (Microchip Technology Incorporated)
• Inventors: Brooks, Steven W., Pickle, Paul
• Primary Examiner(s): Patel, Rajnikant B.
• Application Number:
  US10/424,549
• Publication Number:
  US 20040041543A1
• Time in Patent Office: 935 Days
• Field of Search: 323/282, 323/283, 323/272, 323/285, 323/271, 323/224, 323/290, 323/288, 363/65, 363/66, 363/67, 363/70, 363/48, 363/72
• US Class Current: 323/282
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel

Abstract

A plurality of single-phase synchronizing converter automatically synchronize on a peer-to-peer basis. Each synchronizing converter is configured as a DC-to-DC converter. The synchronizing converters operate in parallel as a multi-phase converter. A common bus between the synchronizing converters includes a sync line and a common phase control line. Proper phasing automatically occurs when power is applied, and the phasing changes automatically as converters are added or removed. When the system powers up, the converters arbitrate for phase position. The phasing positions are random, but the phasing is relatively symmetrical regardless of the number of phases. Preferably, a hot-swappable converter module can be plugged into any location of a parallel multiphase bus to produce a common output voltage. When an additional module is plugged in, the converters readjust their phases to maintain phase symmetry. Preferably, each module shares a substantially equal portion of the output load.

Claims

1. A power supply system comprising:

a first single-phase synchronizing converter that produces output power having a first phase, the first single-phase synchronizing converter configured to automatically synchronize with at least one other power converter to produce phase symmetry between the first phase and one or more phases of the at least one other power converter; and

a common phase control bus, wherein the first single-phase synchronizing converter provides a channel pulse to the common phase control bus.

2. A power supply system further comprising:

a first single-phase synchronizing converter that produces output power having a first phase, the first single-phase synchronizing converter configured to automatically synchronize with at least one other power converter to produce phase symmetry between the first phase and one or more phases of the at least one other power converter; and

a common phase control bus, wherein the first single-phase synchronizing converter provides a pulse to the common phase control bus, the pulse indicating a phase of the single-phase synchronizing converter.

3. The power supply system of claim 2, wherein the single-phase synchronizing converter uses a tn-state driver to provide the pulse to the common phase control bus.

4. The power supply system of claim 2, wherein the common phase control bus carries time and amplitude information.

5. A power supply system of comprising:

a first single-phase synchronizing converter that produces output power having a first phase, the first single-phase synchronizing converter configured to automatically synchronize with at least one other power converter to produce phase symmetry between the first phase and one or more phases of the at least one other power converter; and

a sync bus, wherein the single-phase synchronizing converter provides a sync pulse to the sync bus to indicate a start of a cycle of the power supply system.

6. A power supply system further comprising:

a first single-phase synchronizing converter that produces output power having a first phase, the first single-phase synchronizing converter configured to automatically synchronize with at least one other power converter to produce phase symmetry between the first phase and one or more phases of the at least one other power converter; and

a loadshare bus, wherein the first single-phase synchronizing converter provides a signal to the loadshare bus to indicate an amount of current the first single-phase synchronizing converter is supplying to a load connected to the power supply system.

7. A power supply system comprising a first single-phase synchronizing converter that produces output power having a first phase, the first single-phase synchronizing converter configured to automatically synchronize on a peer-to-peer basis with at least one other single-phase power converter to produce phase symmetry between the first phase at least one phase of the at least one other single-phase power converter to produce a multi-phase converter.

8. The power supply system of claim 7, wherein the first single-phase synchronizing converter is provided to a sync line and to a common phase control line.

9. The power supply system of claim 7, wherein the single-phase synchronizing converter comprises a feedback loop to control the first phase by adjusting the first phase to fall between a previous power pulse produced by a first peer of the single-phase synchronizing converter and a subsequent power pulse produced by a second peer of the single-phase synchronizing converter.

10. A method for adjusting a phase of an output power pulse of a power module, comprising controlling the phase by a feedback loop configured to adjust the first phase to fall between a previous power pulse produced by a first peer of the power module and a subsequent power pulse and a subsequent power pulse produced by a at least one other power module.

11. A power supply system comprising:

a first converter that produces output power according to a first phase;

a second converter that produces output power according to a second phase, the first and second converters each configured to automatically synchronize on a peer-to-peer basis to produce phase symmetry between the first phase and the second phase; and

a common phase control bus, wherein the first converter provides a first channel pulse to the common phase control bus, the second converter provides a second channel pulse to the common phase control bus, and the first converter uses a tri-state driver to provide the first channel pulse to the common phase control bus.

12. A power supply system comprising:

a first converter that produces output power according to a first phase;

a second converter that produces output power according to a second phase, the first and second converters each configured to automatically synchronize on a peer-to-peer basis to produce phase symmetry between the first phase and the second phase; and

a sync bus, wherein a faster of the first converter and the second converter provides a sync pulse to the sync bus to indicate a start of a cycle of the power supply system.

13. A power supply system comprising:

a first converter that produces output power according to a first phase;

a second converter that produces output power according to a second phase, the first and second converters each configured to automatically synchronize on a peer-to-peer basis to produce phase symmetry between the first phase and the second phase; and

a loadshare bus, wherein;

the first converter provides a signal to the loadshare bus to indicate an amount of current the first single-phase synchronizing converter is supplying to a load connected to the power supply system; and

the second converter provides a signal to the loadshare bus to indicate an amount of current the second synchronizing converter is supplying to the load.

14. A power supply system comprising:

a first converter that produces output power according to a first phase;

a second converter that produces output power according to a second phase, the first and second converters each configured to automatically synchronize on a peer-to-peer basis to produce phase symmetry between the first phase and the second phase; and

a shutdown bus, wherein the first converter provides a signal to the shutdown bus to shutdown the first converter and the second converter.

15. A power supply system comprising:

a first converter that produces output power according to a first phase; and

a second converter that produces output power according to a second phase, the first and second converters each configured to automatically synchronize on a peer-to-peer basis to produce phase symmetry between the first chase and the second phase, wherein the first converter is configured to start a first timer at the end of a first second-channel pulse produced by the second converter, the first converter farther configured to end the first timer and start a second timer at a start of a first-channel pulse produced by the first converter, the first converter further configured to stop the second timer at a start of a second second-channel pulse produced by the second converter, the first converter configured to adjust a timing of the first-channel pulse to approximately equalize times measured by the first timer and the second timer.

16. A power supply system comprising:

a first converter that produces output power according to a first phase; and

a second converter that produces output power according to a second phase, the first and second converters each configured to automatically synchronize on a peer-to-peer basis to produce phase symmetry between the first phase and the second phase, wherein the first converter produces first channel pulses and the second channel produces second channel pulses, the first channel configured to adjust a phase of the first channel pulses to fall between the second channel pulses.

17. A power supply system comprising:

a first converter that produces output power according to a first phase; and

a second converter that produces output power according to a second phase, the first and second converters each configured to automatically synchronize on a peer-to-peer basis to produce phase symmetry between the first phase and the second phase, wherein the first converter produces first channel pulses and the second channel produces second channel pulses, the first channel configured to adjust a phase of the first channel pulses to fall between the second channel pulses, the second channel configured to adjust a phase of the second channel pulses to fall between the first channel pulses.

18. A power supply system comprising:

a first converter that produces output power according to a first phase; and

a second converter that produces output power according to a second phase, the first and second converters each configured to automatically synchronize on a peer-to-peer basis to produce phase symmetry between the first phase and the second phase, wherein the first converter produces first channel pulses and the second channel produces second channel pulses, the first channel configured to adjust a phase of the first channel pulses to produce phase symmetry with respect to the second channel pulses.

19. A method of auto-interleaving each channel in a multiphase switching converter, the method comprising:

starting a first timer in a first channel;

resetting the first timer if a second channel outputs a second-channel pulse;

stopping the first timer and starting a second timer when the first channel generates a first-channel pulse;

stopping the second timer when a third channel outputs a third-channel pulse;

adjusting a time of the first-channel pulse to cause the first-channel pulse to start approximately halfway between an end of the second-channel pulse and a start of the third-channel pulse;

converting voltages at respective input terminals of inductors into sensed voltages, wherein the sensed voltages are proportional to respective duty cycles of respective voltage waveforms across the respective inductors, one of the sensed voltages being a reference sensed voltage, the others of the sensed voltages being slave sensed voltages;

comparing the slave sensed voltages to the reference sensed voltage;

generating respective offset voltages based on respective differences between each of the slave sensed voltages and the reference sensed voltage; and

adjusting duty cycles of the voltage waveforms in accordance with respective offset voltages to achieve equal sensed voltages.

20. A multiphase switching converter, comprising:

means for sensing a start of a converter cycle;

means for producing a sync pulse at the start of each converter cycle; and

means for adjusting phases to achieve phase symmetry within a converter cycle through peer-to-peer arbitration.

21. A multiphase switching converter, comprising:

means for converting voltage waveforms at respective input terminals of respective inductors into respective sensed voltages;

means for comparing the sensed voltages;

means for adjusting duty cycles of the respective voltage waveforms to achieve equal sensed voltages; and

means for adjusting phases of the respective voltage waveforms to produce phase symmetry.