Methods and apparatus for a multiphase power regulator

• US 8,598,857 B2
• Filed: 12/11/2008
• Issued: 12/03/2013
• Est. Priority Date: 12/19/2005
• Status: Active Grant

• Current Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Original Assignee: Infineon Technologies Austria Ag (Infineon Technologies AG)
• Inventors: Pierson, Richard, Southwell, Scott, Tang, Benjamim, Ng, Timothy M., Guo, Jinghong, Ostrom, Kenneth A.
• Primary Examiner(s): Behm, Harry
• Application Number:
  US12/333,003
• Publication Number:
  US 20090121695A1
• Time in Patent Office: 1,818 Days
• Field of Search: 323/283, 323/284, 323/272, 341/159, 341/142, 363/65
• US Class Current: 323/283
• CPC Class Codes: H02M 3/1584 with a plurality of power processing stages connected in parallel

Abstract

Methods and apparatus for a multiphase power regulator according various aspects of the present invention operate in conjunction with an active transient response (ATR) system for applying a correction signal to a multiphase pulse width modulator. In the event of a transient, the ATR system may adjust the output of the pulse width modulator to quickly respond to load requirements. The output may be modified by adding pulses, blanking pulses, advancing pulses, and scaling pulses to one or more phases.

Claims

1. A power regulator having multiple phases and configured to generate an output signal for a load, comprising:

a multiphase pulse width modulator adapted to generate synchronous pulse width modulated signals on the multiple phases; and

an active transient response (ATR) system coupled to the multiphase pulse width modulator, wherein the ATR system is adapted to;

identify a transient event in the output signal corresponding to load voltage excursions at the load;

generate asynchronous pulses independently for each phase based on an instantaneous current in each phase or a relative position of the synchronous pulse width modulated signals generated by the multiphase pulse width modulator on the multiple phases, for controlling the phases of the power regulator in response to the transient event; and

control a generation, a duration, and a position of the asynchronous pulses to minimize the load voltage excursions.

2. A power regulator according to claim 1, wherein the ATR system is adapted to identify the transient event by comparing a voltage of the output signal to a plurality of ATR thresholds.

3. A power regulator according to claim 2, wherein the ATR system is adapted to adjust the ATR thresholds according to a state of the load.

4. A power regulator according to claim 1, wherein the ATR system comprises a fine resolution pulse width modulator including an interpolator, wherein the fine resolution pulse width modulator is adapted to control the pulse width modulated signals on the multiple phases in response to the transient event.

5. A power regulator according to claim 1, wherein the ATR system comprises:

an ATR comparator circuit adapted to;

monitor the output signal; and

identify the transient event in the output signal; and

an ATR control system responsive to the ATR comparator circuit and adapted to;

generate the asynchronous pulses for controlling the phases of the power regulator in response to the transient event; and

control a generation, a duration, and a position of the asynchronous pulses to minimize the load voltage excursions.

6. A power regulator for powering a load, comprising:

an output stage;

a pulse width modulator connected to the output stage and adapted to control an output signal of the output stage;

an ATR system connected to the pulse width modulator and comprising a fine resolution pulse width modulator including an interpolator, wherein the ATR system is adapted to;

monitor the output signal of the output stage;

identify a transient event in the output signal and adjust the operation of the pulse width modulator by the fine resolution pulse width modulator causing the pulse width modulator to generate asynchronous pulses for controlling the output stage in response to the transient event; and

control, by the fine resolution pulse width modulator, a generation, a duration, and a position of the asynchronous pulses to minimize load voltage excursions at the output stage.

7. A power regulator according to claim 6, wherein the ATR system is adapted to identify the transient event by comparing a voltage of the output to a plurality of ATR thresholds.

8. A power regulator according to claim 7, wherein the ATR system is adapted to adjust the ATR thresholds according to a state of the load.

9. A power regulator according to claim 6, wherein the ATR system is adapted to generate the asynchronous pulses independently for each phase according to a magnitude of the transient event from a target voltage.

10. A power regulator according to claim 6, wherein the ATR system comprises:

an ATR comparator circuit adapted to;

monitor the output signal; and

identify the transient event in the output signal.

11. In a multiphase power regulator system using pulse width modulation signals to control an output voltage for a load, a method of responding to a transient event in the output voltage, comprising:

detecting a magnitude of the transient event of the output voltage from a target voltage, the transient event corresponding to load voltage excursions at the load;

adjusting operation of a pulse width modulator which generates the pulse width modulation signals on multiple phases, by applying asynchronous pulses to the phases according to the magnitude of the transient event, wherein the asynchronous pulses are generated independently for each phase based on an instantaneous current in each phase or a relative position of the pulse width modulated signals generated by the pulse width modulator on the multiple phases, wherein the asynchronous pulses minimize the load voltage excursions and comprise at least one of;

advanced pulse width modulated pulses in a phase of the pulse width modulation signals;

scaled pulse width modulated pulses in a phase of the pulse width modulation signals; and

blanked pulse width modulated pulses in a phase of the pulse width modulation signals.