LOW POWER DETECTION OF WIRELESS POWER DEVICES

• US 20120025624A1
• Filed: 02/17/2011
• Published: 02/02/2012
• Est. Priority Date: 07/28/2010
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Lee, Kevin D., Low, Zhen Ning, Carobolante, Francesco
• Granted Patent: US 9,853,478 B2
• Time in Patent Office: Days
• US Class Current: 307/104
• CPC Class Codes: H02J 50/12 of the resonant type
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H02J 50/90 involving detection or optimisation of position, e.g. alignment
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge

Abstract

Exemplary embodiments are directed to detection and validation of wirelessly chargeable devices positioned within a charging region of a wireless power transmitter. A device may include a wireless power transmitter configured detect a change in at least one parameter at the transmitter. The transmitter may further be configured to determine whether at least one valid chargeable device is positioned within a charging region of the transmitter upon detecting the change in the at least one parameter.

Claims

1. A device, comprising:

a wireless power transmitter configured to detect a change in at least one parameter at the wireless power transmitter and determine whether at least one valid chargeable device is positioned within a charging region of the wireless power transmitter upon detecting the change in the at least one parameter.

2. The device of claim 1, the at least one parameter comprising at least one of a current level at the transmitter, a resonant frequency of the transmitter, and an amount of reactance at the transmitter.

3. The device of claim 1, the transmitter further configured to measure an amount of current at a power amplifier of the transmitter.

4. The device of claim 3, the transmitter further configured to reduce a power level of the transmitter prior to measuring an amount of current.

5. The device of claim 1, the transmitter further configured to compare a measured amount of current at an associated power amplifier to a baseline current to detect a change in a current level at the transmitter.

6. The device of claim 1, the transmitter further configured to attempt to establish a communication link with a chargeable device to determine whether at least one valid chargeable device is present within an associated charging region.

7. The device of claim 1, the transmitter further configured to initiate a time delay if a current level at the transmitter is substantially equal to a baseline current.

8. The device of claim 7, the transmitter further configured to reduce a power level thereof prior to initiating the time delay.

9. The device of claim 1, the transmitter further configured to set a previously measured current level as a baseline current level if at least one valid chargeable device is not positioned within a charging region of the transmitter.

10. The device of claim 1, the transmitter including a load sensing circuit configured to measure a current level at a power amplifier within transmit circuitry of the transmitter.

11. A method, comprising:

detecting a change in at least one parameter at a wireless power transmitter; and

determining whether at least one valid chargeable device is positioned within an associated charging region of the wireless power transmitter when the change in the at least one parameter is detected.

12. The method of claim 11, the detecting comprising detecting a change in at least one of a current level at the transmitter, a resonant frequency of the transmitter, and an amount of reactance at the transmitter.

13. The method of claim 12, the detecting the change in a current level comprising comparing a measured current level to a baseline current level.

14. The method of claim 13, further comprising setting the baseline current level as the measured current level if the at least one valid chargeable device is not positioned within the associated charging region.

15. The method of claim 11, further comprising reducing a power level of the wireless power transmitter prior to detecting a change in the at least one parameter.

16. The method of claim 11, further comprising measuring and storing a baseline current level within the wireless power transmitter.

17. The method of claim 11, further comprising initiating a time delay if a measured current level at the wireless power transmitter is substantially equal to a baseline current.

18. The method of claim 17, further comprising reducing a power level of the wireless power transmitter prior to initiating the time delay.

19. The method of claim 11, the determining comprising attempting to establish communication with the at least one valid chargeable device upon detecting a change in the current level.

20. A device, comprising:

means for detecting a change in at least one parameter at a wireless power transmitter; and

means for determining whether at least one valid chargeable device is positioned within an associated charging region of the wireless power transmitter when the change in the at least one parameter is detected.

21. The device of claim 20, further comprising means for detecting a change in a current level at the wireless power transmitter.

22. The device of claim 21, the means for detecting a change in the current level comprising means for comparing a measured current level to a baseline current level.

23. The device of claim 20, the means for determining comprising means for attempting to establish communication with the at least one valid chargeable device upon detecting a change in the current level.