Prioritization-based power management protocol in a computer system

• US 6,498,460 B1
• Filed: 12/14/2001
• Issued: 12/24/2002
• Est. Priority Date: 12/14/2001
• Status: Expired due to Term

• Current Assignee: Hewlett-Packard Development Company, L.P. (HP Inc.)
• Original Assignee: Compaq Information Technologies Group LP (HP Inc.)
• Inventors: Atkinson, Lee W.
• Primary Examiner(s): Tso, Edward H.
• Application Number:
  US10/017,018
• Time in Patent Office: 375 Days
• Field of Search: 320/127, 320/128, 320/132, 320/135, 320/137, 320/DIG.11, 363/15, 363/19, 363/21
• US Class Current: 320/135
• 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 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/324 by lowering clock frequency
• CPC Class Codes: G06F 1/3265 Power saving in display device
• CPC Class Codes: Y02D 10/00 Energy efficient computing, e.g. low power processors, power management or thermal management

Abstract

A power management scheme for a computer system prioritizes battery charging. The scheme includes determining when the output of a power adapter, which powers a computer and a battery subsystem, has reached or is about to reach a threshold which may be the power budget for the computer system. When this happens, rather than throttling battery charging, the system throttles back an aspect of the computer. Alternatively, after the computer has been throttled back, if the power budget still is being exceeded or is about to be exceeded again, then battery charging can be throttled back. In yet another embodiment, battery charging can be throttled first, followed, if necessary, by computer throttling.

Claims

1. A power management method for a computer system which includes a computer coupled to a battery subsystem, said battery subsystem including a charger and a rechargeable battery which can be used to power said computer, said method comprising:

(a) determining the power draw on a power adapter; and

(b) throttling back said computer if said power draw exceeds a threshold.

2. The method of claim 1 wherein (b) includes reducing the clock frequency to a processor in said computer.

3. The method of claim 1 wherein (b) includes dimming a display in said computer.

4. The method of claim 1 wherein (a) includes measuring the current output of said power adapter.

5. The method of claim 1 wherein (a) includes monitoring the charge on said battery.

6. The method of claim 1 including determining that the power draw exceeds a threshold from the time battery charging begins until the power consumption by the battery charger approximately reaches a maximum level.

7. A power management method for a computer system which includes a computer coupled to a battery subsystem, said battery subsystem including a charger and a rechargeable battery which can be used to power said computer, said method comprising:

(a) determining the power draw on a power adapter;

(b) throttling back said computer if said power draw exceeds a threshold; and

(c) throttling back battery charging if said power draw exceeds said threshold.

8. The method of claim 7, wherein (c) occurs after (b).

9. The method of claim 7 wherein (b) includes reducing the clock frequency to a processor in said computer.

10. The method of claim 7 wherein (b) includes dimming a display in said computer.

11. The method of claim 7 wherein (a) includes measuring the current output of said power adapter.

12. The method of claim 7 wherein (a) includes monitoring the charge on said battery.

13. The method of claim 7 including determining that the power draw exceeds a threshold from the time battery charging begins until the power consumption by the battery charger approximately reaches a maximum level.

14. A computer system, comprising:

a power adapter;

a computer coupled to said power adapter;

a battery charger coupled to said power adapter;

a battery coupled to said battery charger;

throttle logic coupled to said computer, said throttle logic throttles back said computer when the power draw on said power adapter exceeds a threshold.

15. The computer system of claim 14, wherein said computer includes a processor which operates from a clock signal at an adjustable frequency, and wherein said throttle logic throttles back the computer by causing the frequency of said clock to decrease.

16. The computer system of claim 14 wherein said computer includes a display with adjustable brightness and wherein said throttle logic throttles back the computer by causing said display to be dimmed.

17. The computer system of claim 14 wherein (a) includes measuring the current output of said power adapter.

18. The computer system of claim 14 wherein said throttle logic determines when said threshold is exceeded by monitoring the charge on said battery.

19. The computer system of claim 14 wherein said throttle logic determines when said threshold is exceeded from the time battery charging begins until the power consumption by the battery charger approximately reaches a maximum level.

20. A computer system, comprising:

a power adapter;

a computer coupled to said power adapter;

a battery charger coupled to said power adapter;

a battery coupled to said battery charger;

throttle logic coupled to said computer, said throttle logic throttles back said computer when the power draw on said power adapter exceeds a threshold and throttles back battery charging if said power draw exceeds another threshold.

21. The computer system of claim 20, wherein said throttle logic throttles back battery charging after throttling back the computer.

22. The computer system of claim 20 wherein said throttle logic throttles back the computer after throttling back battery charging.

23. The computer system of claim 20 wherein said computer includes a display with adjustable brightness and wherein said throttle logic throttles back the computer by causing said display to be dimmed.

24. The computer system of claim 20 wherein said computer includes a processor which operates from a clock signal at an adjustable frequency, and wherein said throttle logic throttles back the computer by causing the frequency of said clock to decrease.

25. The computer system of claim 20 further including a current sense circuit coupled to the output of said power adapter and said throttle logic, and wherein said throttle logic determines if the threshold is exceeded by monitoring a signal from the current sense circuit which indicates the level of current at the output of the power adapter.

26. The computer system of claim 20 wherein said battery charger includes a fuel gauge which provides parameters regarding the charge on said battery, and wherein said throttle logic determines if the threshold is exceeded monitoring the charge on said battery.

27. The computer system of claim 20 wherein said battery charger includes a fuel gauge which provides parameters regarding the charge on said battery, and wherein said throttle logic determines that the threshold is exceeded from the time battery charging begins until the power consumption by the battery charger approximately reaches a maximum level.

28. A computer system, comprising:

a power adapter;

a computer coupled to said power adapter;

a battery charger coupled to said power adapter;

a battery coupled to said battery charger;

a display on which a graphical user interface is provided to permit a user to select one of plurality of throttle protocols wherein said protocols at least include a protocol by which said battery charging is prioritized higher than computer performance; and

throttle logic coupled to said computer and said battery charger, said throttle logic throttles back either said computer or said battery charger when the power draw on said power adapter exceeds a threshold in accordance with the protocol selected by a user.

29. A computer system, comprising:

a power adapter;

a computer coupled to said power adapter;

a battery charger coupled to said power adapter;

a battery coupled to said battery charger; and

throttle logic coupled to said computer and said battery charger, said throttle logic throttles back either said computer or said battery charger when the power draw on said power adapter exceeds a threshold in accordance with a throttle protocol set in the system;

wherein said throttle protocol is determined in accordance of whether the system is docked.

30. The system of claim 29 wherein a throttle protocol is used which prioritizes the computer over battery charging if the system is docked.

31. The system of claim 30 wherein another throttle protocol is used which prioritizes battery charging over the computer if the system is not docked.

32. The system of claim 29 wherein a throttle protocol is used which prioritizes battery charging over the computer if the system is not docked.