Pulse frequency modulation regulation and exit scheme using single comparator for power converter

Patent metadata

Field	Value
Publication number	US-2025062674-A1
Application number	US-202318450552-A
Country	US
Kind code	A1
Filing date	Aug 16, 2023
Priority date	Aug 17, 2022
Publication date	Feb 20, 2025
Grant date	—

Abstract

A method may include, when in a low-power mode of a power converter, monitoring an output voltage of the power converter; comparing, with a single comparator, the output voltage to a first threshold voltage and cause the power converter to enter a magnetization phase of the low-power mode responsive to the output voltage falling below the first threshold voltage; and during the magnetization phase and a demagnetization phase of the low-power mode, comparing, with the single comparator, the output voltage to a second threshold voltage lower than the first threshold voltage and cause the power converter to enter the high-power mode responsive to the output voltage falling below the second threshold voltage.

First claim

1 . A system comprising:
a power converter for regulating an output voltage at an output of the power converter; power management circuitry configured to enable operation of the power converter, including one or more first components critical to operation of the power converter in a high-power mode and one or more second components critical to operation of the power converter in both the high-power mode and a low-power mode in which the system consumes significantly less power than that of the high-power mode; and a controller configured to, when in the low-power mode:
monitor an output voltage of the power converter;
compare, with a single comparator of the controller, the output voltage to a first threshold voltage and cause the power converter to enter a magnetization phase of the low-power mode responsive to the output voltage falling below the first threshold voltage; and
during the magnetization phase and a demagnetization phase of the low-power mode, compare, with the single comparator, the output voltage to a second threshold voltage lower than the first threshold voltage and cause the power converter to enter the high-power mode responsive to the output voltage falling below the second threshold voltage.

2 . The system of claim 1 , wherein the controller is further configured to, during a switching cycle of the power converter comprising the magnetization phase and the demagnetization phase, compare the output voltage to the first threshold voltage and cause the power converter to re-enter the magnetization phase of the low-power mode responsive to the output voltage again falling below the first threshold voltage.

3 . The system of claim 1 , wherein the controller is further configured to, during one of the magnetization phase and the demagnetization phase, compare the output voltage to the first threshold voltage and cause the power converter to re-enter the magnetization phase of the low-power mode responsive to the output voltage again falling below the first threshold voltage.

4 . The system of claim 1 , wherein the controller is further configured to change, at a predetermined time before an end of the demagnetization phase, a reference voltage of the single comparator to which the output voltage is compared from the second threshold voltage to the first threshold voltage.

5 . The system of claim 1 , wherein the controller is further configured to, during one of the magnetization phase and the demagnetization phase, compare the output voltage to a third threshold voltage lesser than the first threshold voltage and greater than the second threshold voltage, and cause the power converter to re-enter the magnetization phase of the low-power mode responsive to the output voltage falling below the third threshold voltage.

6 . The system of claim 5 , wherein comparing the output voltage to the third threshold voltage is performed by the single comparator.

7 . The system of claim 6 , wherein the controller is further configured to change, at a predetermined time before an end of the demagnetization phase, a reference voltage of the single comparator to which the output voltage is compared from the second threshold voltage to the first threshold voltage.

8 . The system of claim 6 , wherein the controller is further configured to change, at a predetermined time before an end of the demagnetization phase, a reference voltage of the single comparator to which the output voltage is compared from the second threshold voltage to the third threshold voltage.

9 . The system of claim 1 , wherein causing the power converter to operate in the low-power mode comprises causing the power converter to operate in a pulse-frequency modulation mode.

10 . The system of claim 1 , wherein causing the power converter to operate in the low-power mode comprises causing the power converter to operate in discontinuous conduction mode.

11 . The system of claim 1 , wherein causing the power converter to operate in the high-power mode comprises causing the power converter to operate in a pulse-width modulation mode.

12 . The system of claim 1 , wherein causing the power converter to operate in the high-power mode comprises causing the power converter to operate in continuous conduction mode.

13 . A method, in a system having a power converter for regulating an output voltage at an output of the power converter and power management circuitry configured to enable operation of the power converter, including one or more first components critical to operation of the power converter in a high-power mode and one or more second components critical to operation of the power converter in both the high-power mode and a low-power mode in which the system consumes significantly less power than that of the high-power mode, the method comprising, when in the low-power mode:
monitoring an output voltage of the power converter; comparing, with a single comparator, the output voltage to a first threshold voltage and causing the power converter to enter a magnetization phase of the low-power mode responsive to the output voltage falling below the first threshold voltage; and during the magnetization phase and a demagnetization phase of the low-power mode, comparing, with the single comparator, the output voltage to a second threshold voltage lower than the first threshold voltage and causing the power converter to enter the high-power mode responsive to the output voltage falling below the second threshold voltage.

14 . The method of claim 13 , further comprising, during a switching cycle of the power converter comprising the magnetization phase and the demagnetization phase, comparing the output voltage to the first threshold voltage and causing the power converter to re-enter the magnetization phase of the low-power mode responsive to the output voltage again falling below the first threshold voltage.

15 . The method of claim 13 , further comprising, during one of the magnetization phase and the demagnetization phase, comparing the output voltage to the first threshold voltage and causing the power converter to re-enter the magnetization phase of the low-power mode responsive to the output voltage again falling below the first threshold voltage.

16 . The method of claim 13 , further comprising changing, at a predetermined time before an end of the demagnetization phase, a reference voltage of the single comparator to which the output voltage is compared from the second threshold voltage to the first threshold voltage.

17 . The method of claim 13 , further comprising, during one of the magnetization phase and the demagnetization phase, comparing the output voltage to a third threshold voltage lesser than the first threshold voltage and greater than the second threshold voltage, and causing the power converter to re-enter the magnetization phase of the low-power mode responsive to the output voltage falling below the third threshold voltage.

18 . The method of claim 17 , wherein comparing the output voltage to the third threshold voltage is performed by the single comparator.

19 . The method of claim 18 , further comprising changing, at a predetermined time before an end of the demagnetization phase, a reference voltage of the single comparator to which the output voltage is compared from the second voltage to the first threshold voltage.

20 . The method of claim 18 , further comprising changing, at a predetermined time before an end of the demagnetization phase, a reference voltage of the single comparator to which the output voltage is co

Assignees

• Cirrus Logic Int Semiconductor Ltd

Inventors

• Alevoor Shashank
• Maru Siddharth
• Gallina Pietro
• Gupta Chanchal
• Parasuram Vivek

Classifications

• H02M3/158

  including plural semiconductor devices as final control devices for a single load · CPC title

• H02M3/1566 Primary

  with means for compensating against rapid load changes, e.g. with auxiliary current source, with dual mode control or with inductance variation · CPC title

• H02M1/0032

  Control circuits allowing low power mode operation, e.g. in standby mode · CPC title

• H02M1/0025 Primary

  Arrangements for modifying reference values, feedback values or error values in the control loop of a converter · CPC title

• H02M3/156 Primary

  with automatic control of output voltage or current, e.g. switching regulators · CPC title