Automatic shut off of backup power source in the extended absence of AC power

• US 7,411,314 B2
• Filed: 08/19/2003
• Issued: 08/12/2008
• Est. Priority Date: 08/19/2003
• Status: Active Grant

• Current Assignee: Intel Corporation
• Original Assignee: Intel Corporation
• Inventors: Dunstan, Robert A.
• Primary Examiner(s): Sherry; Michael J
• Assistant Examiner(s): RUTLAND WALLIS, MICHAEL
• Application Number:
  US10/644,683
• Publication Number:
  US 20050041351A1
• Time in Patent Office: 1,820 Days
• Field of Search: 307/66, 307/64, 714/24
• US Class Current: 307/64
• CPC Class Codes: G06F 1/3203 Power management, i.e. event-based initiation of a power-saving mode
• CPC Class Codes: G06F 1/3246 by software initiated power-off

Abstract

A system is provided with the ability to automatically shut off a backup power source from further sourcing power for the system, when AC is absent, after the backup power source has sourced power for the system for a period of time.

Claims

1. In an apparatus, a method of operation comprising:

powering the apparatus from a backup power source, in response to the apparatus being in an AC absence condition;

initiating, by an Operating System of the apparatus in response to the apparatus being in the AC absence condition, a suspend to memory process to place the apparatus in a suspended to memory state wherein an operational state of the apparatus is saved to volatile memory requiring a source of electrical power to sustain the suspended to memory state, and wherein no further activity occurs while the apparatus is in the suspended to memory state including suspension of all data transmissions;

setting, by a BIOS of the apparatus upon the initiation of the suspend to memory process, a timer to initiate waking up of the apparatus after a period of time and to facilitate shutting off the backup power source; and

canceling, by the BIOS, the timer as part of a resume process initiated in response to AC power being re-present at the apparatus.

2. The method of claim 1, wherein the timer is a real time clock (RTC) to initiate waking of the apparatus after the period of time, to facilitate the shutting off of the backup power source.

3. The method of claim 2, wherein the basic input/output system (BIOS) is adapted to schedule the RTC to initiate waking of the apparatus after the period of time.

4. The method of claim 2, wherein the method further comprises the RTC initiating waking of the apparatus, after passing of the period of time, including as part of waking of the apparatus, a basic input/output system (BIOS) causing the backup power source to be shut off, transitioning the apparatus to an un-powered state instead.

5. The method of claim 4, wherein the BIOS causes the backup power source to be shut off as part of the waking of the apparatus if AC remains absent.

6. The method of claim 1, wherein the method further comprises

the timer expiring after passing of the period of time;

and

a companion logic of the timer shutting off of the backup power source, placing the apparatus in an un-powered state.

7. The method of claim 6, wherein the timer shuts off the backup power source if AC remains absent.

8. The method of claim 1, wherein the method further comprises

monitoring for absence of AC to the power supply;

and

generating a signal indicating AC absence on detection of absence of AC to the power supply.

9. The method of claim 8, wherein the monitoring and generating are performed by the power supply.

10. The method of claim 1, wherein the method further comprises accepting by the apparatus a specification of the period of time.

11. A system comprising:

a power supply to supply power to the system, including a backup power source to supply power during absence of AC to the power supply; and

an arrangement coupled to the power supply to shut off the power supply, after initiating, by an Operating System of the apparatus in response to the apparatus being in an AC absence condition, a suspend to memory process to place the system in a suspended to memory state wherein an operational state of the apparatus is saved to volatile memory requiring a source of electrical power to sustain the suspended to memory state, and wherein no further activity occurs while the system is in the suspended to memory state including suspension of all data transmissions, and after the expiration of a timer set, by a BIOS of the apparatus upon the initiation of the suspend to memory process, to expire after a period of time, the BIOS adapted to cancel the timer as part of a resume process to place the system in an active state in response to AC power re-presence.

12. The system of claim 11, wherein the arrangement comprises a real time clock (RTC) employable to initiate waking of the system after the period of time, to facilitate shutting off of the backup power source.

13. The system of claim 12, wherein the basic I/O system (BIOS) is adapted to schedule the RTC to initiate waking of the system after the period of time.

14. The system of claim 12, wherein the basic I/O system (BIOS) equipped to cause the backup power source to be shut off when the RTC initiates waking of the system.

15. The system of claim 13, wherein the BIOS is further equipped to cause the backup power source to be shut off if AC remains absent.

16. The system of claim 11, wherein the system further comprises a circuit coupled to the timer to generate a shut off signal to shut off the backup power off, at the expiration of the timer.

17. The system of claim 16, wherein the circuit is further equipped to receive a AC condition signal indicating whether AC presence or absence, and condition the generation of the shut off signal based on the AC condition signal.

18. The system of claim 11 wherein the system further comprises a controller to control at least a selected one of an input and an output of the system, and the timer is a part of the controller.

19. The system of claim 11, wherein the timer is a part of the power supply.

20. The system of claim 11, wherein the arrangement is further equipped to accept for the system a specification of the period of time.

21. The system of claim 11, wherein the system further comprises a networking interface.

22. A power supply comprising:

an output interface;

a backup power source; and

a switch conditionally coupling the integral backup power source to the output interface to output power through the output interface during absence of AC to the power supply, including a control interface accessible during a suspended to memory state of a host device hosting the power supply to allow the backup power source to be uncoupled from the output interface to stop the backup power source from outputting power through the output interface after the host device has entered the suspended to memory state, during which state no data are transmitted, said suspended to memory state initiated by an Operating System of the host device in response to the AC absence condition and wherein an operational state of the host device is saved to volatile memory requiring a source of electrical power to sustain the suspended to memory state and further after the expiration of a timer set, by a BIOS of the host device upon the initiation of the suspended to memory process, to expire after a period of time, the BIOS adapted to cancel the timer as part of a resume process to place the system in an active state in response to AC power re-presence.

23. The power supply of claim 22, wherein the power supply further comprises a monitor to monitor for presence or absence of AC to the power supply, and to generate a signal indicating the presence or absence of AC accordingly.

24. The power supply of claim 22, wherein the power supply further comprises a timer settable to expire after the period of time to shut off the backup power source.

25. An article of manufacture comprising:

a storage medium;

a plurality of programming instruction stored therein, designed to enable an apparatus to be able to perform, when the apparatus is in an AC absence condition;

setting a real time clock (RTC) to initiate waking of the apparatus after the apparatus has been placed into a suspended to memory state initiated by an Operating System of the apparatus in response to the AC absence condition, under which state no data are transmitted, and wherein an operational state of the apparatus is saved to volatile memory requiring a source of electrical power to sustain the suspended to memory state and to shut off a backup power source of the apparatus upon the expiration of a timer set, upon the initiation of the suspend to memory process, to expire after a period of time; and

cancel the timer as part of a resume process to put the apparatus in an active state initiated in response to AC power being re-present at the apparatus.

26. The article of claim 25, wherein the programming instructions are further designed to enable the apparatus to perform the setting operation, when intervening in a process to suspend the apparatus.

27. The article of claim 25, wherein the programming instructions are further designed to enable the apparatus to shut off the backup power source when the RTC initiates waking of the apparatus after passing of the time period.

28. The article of claim 27, wherein the programming instructions are further designed to enable the apparatus to perform the shut off conditioned on AC remains absent at the apparatus.

29. The article of claim 25, wherein the programming instructions implement the enabling of the apparatus to perform f the setting operation as part of the basic input/output system (BIOS).