Power management systems with controllable adapter output

• US 20090001937A1
• Filed: 06/12/2008
• Published: 01/01/2009
• Est. Priority Date: 03/07/2007
• Status: Active Grant

• Current Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Original Assignee: O2 Micro International Limited (O2 Micro Incorporated)
• Inventors: Liu, Liusheng, Densham, William, Kao, Han-Jung
• Granted Patent: US 7,973,515 B2
• Time in Patent Office: Days
• US Class Current: 320/145
• CPC Class Codes: H02J 2207/20 Charging or discharging characterised by the power electronics converter
• CPC Class Codes: H02J 7/00 Circuit arrangements for charging or depolarising batteries or for supplying loads from batteries
• CPC Class Codes: H02J 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: H02J 7/00714 in response to battery charging or discharging current
• CPC Class Codes: H02J 7/007182 in response to battery voltage
• CPC Class Codes: H02J 7/02 for charging batteries from ac mains by converters
• CPC Class Codes: H02J 7/04 Regulation of charging current or voltage

Abstract

A power management system includes a battery pack having a battery controller and includes an adapter operable for charging the battery pack and powering a system load. The adapter generates a power recognition signal indicative of a maximum adapter power and receives a control signal. The battery controller in the battery pack receives the power recognition signal and generates the control signal to adjust an output power of the adapter according to a status of the battery pack and a status of the system load.

Claims

1. A power management system comprising:

an adapter operable for charging a battery pack and powering a system load, for generating a power recognition signal indicative of a maximum adapter power, and for receiving a control signal; and

a battery controller in said battery pack for receiving said power recognition signal and for generating said control signal to adjust an output power of said adapter according to a status of said battery pack and a status of said system load.

2. The power management system as claimed in claim 1, wherein said status of said battery pack comprises a level of a charging current of said battery pack.

3. The power management system as claimed in claim 1, wherein said status of said battery pack comprises a status of each cell of a plurality of cells in said battery pack.

4. The power management system as claimed in claim 1, wherein said battery controller receives a monitoring signal indicative of an output current of said adapter.

5. The power management system as claimed in claim 4, wherein said battery controller adjusts a charging current of said battery pack according to said monitoring signal.

6. The power management system as claim in claim 1, wherein said adapter comprises a pulse width modulation signal generator operable for generating a pulse width modulation signal, and wherein a duty cycle of said pulse width modulation signal is controlled by said control signal.

7. The power management system as claimed in claim 1, wherein said battery pack comprises a monitoring circuit for monitoring each cell of a plurality of cells in said battery pack and for generating a monitoring signal indicating a status of each cell to said battery controller.

8. The power management system as claimed in claim 1, wherein said control signal comprises an analog control signal.

9. The power management system as claimed in claim 1, wherein said control signal comprises a digital control signal.

10. The power management system as claimed in claim 1, wherein said power recognition signal and said control signal are transferred through a single bus.

11. The power management system as claimed in claim 1, further comprising:

a switch coupled between said adapter and said battery pack,

wherein said battery controller generates a signal to switch off said switch if an undesirable condition of said adapter occurs.

12. A battery pack comprising:

a monitoring circuit for monitoring each cell of a plurality of cells in said battery pack and for generating a monitoring signal indicating a status of each cell; and

a battery controller coupled to said monitoring circuit and for receiving a power recognition signal indicative of a maximum adapter power of an adapter and for generating a control signal for controlling an output power of said adapter according to a status of said battery pack and a status of a system load powered by said adapter.

13. The battery pack as claimed in claim 12, wherein said status of said battery pack comprises a level of a charging current of said battery pack.

14. The battery pack as claimed in claim 12, wherein said status of said battery pack comprises said status of each cell of said plurality of cells.

15. The battery pack as claimed in claim 12, wherein said battery controller receives an adapter monitoring signal indicative of an output current of said adapter.

16. The battery pack as claimed in claim 15, wherein said battery controller further adjusts a charging current of said battery pack according to said adapter monitoring signal.

17. The battery pack as claimed in claim 12, wherein said control signal comprises an analog control signal.

18. The battery pack as claimed in claim 12, wherein said control signal comprises a digital control signal.

19. The battery pack as claimed in claim 12, wherein said power recognition signal and said control signal are transferred through a single bus.

20. The battery pack as claimed in claim 12, wherein said battery controller generates a signal to switch off a switch coupled between said adapter and said battery pack if an undesirable condition of said adapter occurs.

21. A method comprising:

receiving a power recognition signal indicative of a maximum adapter power from an adapter; and

generating a control signal by a battery pack to adjust an output power of said adapter according to a status of said battery pack and a status of a system load powered by said adapter.

22. The method as claimed in claim 21, further comprising:

receiving a monitoring signal indicative of an output current of said adapter.

23. The method as claimed in claim 22, further comprising:

adjusting a charging current of said battery pack according to said monitoring signal.

24. The method as claimed in claim 21, further comprising:

monitoring each cell of a plurality of cells in said battery pack; and

generating a monitoring signal indicating a status of each cell.

25. The method as claimed in claim 21, further comprising:

transferring said power recognition signal and said control signal through a single bus between said adapter and said battery pack.

26. The method as claimed in claim 21, further comprising:

switching off a switch coupled between said adapter and said battery pack if an undesirable condition of said adapter occurs.

27. The method as claimed in claim 21, wherein said status of said battery pack comprises a level of a charging current of said battery pack.

28. The method as claimed in claim 21, wherein said status of said battery pack comprises a status of each cell of a plurality of cells in said battery pack.