Peak current support for a power rail system via a shared secondary power supply

• US 10,642,329 B2
• Filed: 03/23/2016
• Issued: 05/05/2020
• Est. Priority Date: 03/23/2016
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Park, Hee Jun, Kwak, Taewoo, Chun, Christopher Kong Yee
• Primary Examiner(s): Nguyen, Phil K
• Application Number:
  US15/077,949
• Publication Number:
  US 20170277238A1
• Time in Patent Office: 1,504 Days
• Field of Search: 713310
• CPC Class Codes: G06F 1/263 Arrangements for using multiple switchable power supplies, e.g. battery and AC G06F1/30 takes precedence
• CPC Class Codes: G06F 1/266 Arrangements to supply power to external peripherals either directly from the computer or under computer control, e.g. supply of power through the communication port, computer controlled power-strips
• CPC Class Codes: G06F 1/32 Means for saving power

Abstract

Systems, methods, and computer programs are provided for controlling power in a computing device. One embodiment is a system comprising a plurality of power rails coupled to one or more computing device components. Each power rail has a primary power supply for producing current at a corresponding requested voltage. The system further comprises a shared secondary power supply selectively coupled to the plurality of power rails for providing a current increase. A controller selects one of the plurality of power rails to receive the current increase. The controller generates a control signal to electrically couple the shared secondary power supply to the selected power rail to receive the current increase.

Claims

1. A method for controlling power in a computing device, the method comprising:

detecting with a current limit manager whether a current demand on one of a plurality of power rails coupled to an output of a corresponding one of a plurality of primary power supplies has reached a current limit threshold associated with the power rail, the output of each primary power supply being electrically isolated from the outputs of all other primary power supplies and being electrically coupled to exactly one of the power rails, each power rail being coupled to a current limit manager;

in response to detection of the current demand on the power rail reaching the associated current limit threshold, selecting the power rail with a power rail priority controller from among the plurality of power rails to receive a current increase from a shared secondary power supply, the shared secondary power supply having a current output capability, the shared secondary power supply having an output coupled to a plurality of switches, each switch uniquely associated with one of the power rails and each switch being coupled to the power rail priority controller;

the power rail priority controller electrically coupling the output of the shared secondary power supply to the selected power rail via the switch uniquely associated with the selected power rail while the output of the corresponding primary power supply remains coupled to the selected power rail; and

the power rail priority controller increasing the current limit threshold associated with the selected power rail by an amount equal to the current output capability of the shared secondary power supply;

wherein the power rail priority controller selecting the one of the plurality of power rails to receive the current increase comprises;

determining a power rail priority in response to detection of a plurality of current demands on a corresponding plurality of the power rails.

2. The method of claim 1, wherein the power rail priority is determined based on data from one or more limit managers associated with the plurality of power rails.

3. The method of claim 1, wherein the selected power rail is determined based on one or more counts for reaching a current limit threshold.

4. The method of claim 1, wherein the selected power rail is determined based on one or more of a power estimation, a power multiplexer status, a leakage current, and a temperature or frequency of a component requesting the current increase.

5. The method of claim 1, wherein the computing device comprises a battery-powered portable computing device.

6. A system for controlling power in a computing device, the system comprising:

means for detecting whether a current demand on one of a plurality of power rails coupled to an output of a corresponding one of a plurality of primary power supplies has reached a current limit threshold associated with the power rail, the output of each primary power supply being electrically isolated from the outputs of all other primary power supplies and being electrically coupled to exactly one of the power rails, the means for detecting comprising a plurality of current limit managers, each power rail being coupled to a current limit manager; and

a power rail priority controller comprising;

means for, in response to detection of the current demand on the power rail reaching the associated current limit threshold, selecting the power rail from among the plurality of power rails to receive a current increase from a shared secondary power supply, the shared secondary power supply having a current output capability, the shared secondary power supply having an output coupled to a plurality of switches, each switch uniquely associated with one of the power rails and each switch being coupled to the power rail priority controller;

means for electrically coupling the output of the shared secondary power supply to the selected power rail via the switch uniquely associated with the selected power rail while the output of the corresponding primary power supply remains coupled to the selected power rail;

and means for increasing the current limit threshold associated with the selected power rail by an amount equal to the current output capability of the shared secondary power supply;

wherein the means for selecting the one of the plurality of power rails to receive the current increase comprises;

means for determining a power rail priority in response to detection of a plurality of current demands on a corresponding plurality of the power rails.

7. The system of claim 6, wherein the selected power rail is determined based on one or more counts for reaching a current limit threshold.

8. The system of claim 6, wherein the selected power rail is determined based on one or more of a power estimation, a power multiplexer status, a leakage current, and a temperature or frequency of a component requesting the current increase.

9. The system of claim 6, further comprising:

means for multiplexing power inputs from the plurality of power rails to one or more components of the computing device.

10. The system of claim 6, wherein the portable computing device comprises one of a mobile telephone, a personal digital assistant, a pager, a smartphone, a navigation device, and a hand-held computer with a wireless connection.

11. A computer program product for power control in a computing device, the computer program product comprising processor-executable logic embodied in at least one non-transitory storage medium, execution of the logic by one or more processors configuring the computing device to:

detect with a current limit manager whether a current demand on one of a plurality of power rails coupled to an output of a corresponding one of a plurality of primary power supplies has reached a current limit threshold associated with the power rail, the output of each primary power supply being electrically isolated from the outputs of all other primary power supplies and being electrically coupled to exactly one of the power rails, each power rail being coupled to a current limit manager;

in response to detection of the current demand on the power rail reaching the corresponding current limit threshold, select the power rail with a power rail priority controller from among the plurality of power rails to receive a current increase from a shared secondary power supply, the shared secondary power supply having a current output capability, the shared secondary power supply having an output coupled to a plurality of switches, each switch uniquely associated with one of the power rails and each switch being coupled to the power rail priority controller;

the power rail priority controller electrically couple the output of the shared secondary power supply to the selected power rail via a switch uniquely associated with the selected power rail while the output of the corresponding primary power supply remains coupled to the selected power rail; and

the power rail priority controller increase the current limit threshold associated with the selected power rail by an amount equal to the current output capability of the shared secondary power supply;

wherein the power rail priority controller selecting the one of the plurality of power rails to receive the current increase comprises;

determining a power rail priority in response to detection of a plurality of current demands on a corresponding plurality of the power rails.

12. The computer program product of claim 11, wherein the power rail priority is determined based on data from one or more limit managers associated with the plurality of power rails.

13. The computer program product of claim 11, wherein the selected power rail is determined based on one or more counts for reaching a current limit threshold.

14. The computer program product of claim 11, wherein the selected power rail is determined based on one or more of a power estimation, a power multiplexer status, a leakage current, and a temperature or frequency of a component requesting the current increase.

15. The computer program product of claim 11, wherein the computing device comprises a battery-powered portable computing device.

16. A system for controlling power in a computing device, the system comprising:

a plurality of primary power supplies, the output of each primary power supply being electrically isolated from the outputs of all other primary power supplies and being electrically coupled to exactly one of a plurality of power rails;

a plurality of current limit managers, each configured to detect whether a current demand on one of the power rails has reached a current limit threshold associated with the one of the power rails;

a shared secondary power supply selectively coupled to the plurality of power rails via a plurality of switches respectively and uniquely associated with the plurality of power rails, the shared secondary power supply having a current output capability; and

a power rail priority controller coupled to each current limit manager by a signal line, the power rail priority controller configured to;

select one of the plurality of power rails from among the plurality of power rails to receive a current increase in response to detection by one of the current limit managers of the current demand on the power rail reaching the associated current limit threshold;

electrically couple the output of the shared secondary power supply to only the selected power rail via activation of a particular switch uniquely associated with the selected power rail while the output of the corresponding primary power supply remains coupled to the selected power rail; and

increase the current limit threshold associated with the selected power rail by an amount equal to the current output capability of the shared power supply;

wherein the power rail priority controller is further configured to select the one of the plurality of power rails by determining a power rail priority in response to detection of a plurality of current demands on a corresponding plurality of the power rails.

17. The system of claim 16, wherein one or more of the primary power supplies and the shared power supply comprises one of a switched-mode power supply and a low-dropout regulator (LDO), and the shared power supply comprises a dependent current source.

18. The system of claim 16, wherein the power rail priority is determined based on data from one or more limit managers associated with the plurality of power rails.

19. The system of claim 16, wherein the selected power rail is determined based on one or more counts for reaching a current limit threshold.

20. The system of claim 16, wherein the computing device comprises a battery-powered portable computing device.