Waking up a wireless power transmitter from beacon mode

• US 9,306,634 B2
• Filed: 01/17/2012
• Issued: 04/05/2016
• Est. Priority Date: 03/01/2011
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Low, Zhen Ning, Lee, Kevin Douglas
• Primary Examiner(s): Cavallari, Daniel
• Application Number:
  US13/352,122
• Publication Number:
  US 20120223589A1
• Time in Patent Office: 1,540 Days
• US Class Current: 1/1
• 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 50/40 using two or more transmitting or receiving devices H02J50/50 takes precedence
• 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 7/00045 Authentication, i.e. circuits for checking compatibility between one component, e.g. a battery or a battery charger, and another component, e.g. a power source
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer
• CPC Class Codes: Y04S 20/20 End-user application control systems

Abstract

This disclosure provides systems, methods and apparatus for waking a wireless power transmitter from beacon mode. In one aspect a wireless power receiver apparatus is provided. The wireless power receiver apparatus includes a receive circuit comprising a receive coil. This receive circuit is coupled to a load. The receive circuit is configured to wirelessly receive power from a transmitter device at a first power level to power the load. The wireless power receiver apparatus further includes an adjustment circuit configured to be powered by using the wirelessly received power. The adjustment circuit is further configured to adjust a characteristic of the load using the wirelessly received power for a period of time to cause a detectable change in an operating characteristic of the transmitter device for the period of time.

Claims

1. A wireless power receiver apparatus, comprising:

a receive circuit comprising a receive coil, the receive circuit being coupled to a load, the receive circuit being configured to wirelessly receive power from a transmitter device at a first power level or a second power level to power the load, wherein the first power level is lower than the second power level and corresponds to a low power mode of the transmitter device; and

an adjustment circuit configured to be powered by using the wirelessly received power, the adjustment circuit being further configured to adjust a characteristic of the load using the wirelessly received power for a period of time to cause a detectable change in an operating characteristic of the transmitter device for the period of time.

2. The wireless power receiver apparatus of claim 1, wherein the receive circuit is configured to wirelessly receive power from the transmitter device at the second power level in response to the change in the operating characteristic of the transmitter device.

3. The wireless power receiver apparatus of claim 1, wherein the characteristic of the load comprises an impedance of the load.

4. The wireless power receiver apparatus of claim 3, wherein the adjustment circuit is configured to lower the impedance of the load.

5. The wireless power receiver apparatus of claim 1, wherein the adjustment circuit further comprises a switch, wherein the adjustment circuit is configured to adjust the characteristic of the load by altering a position of the switch.

6. The wireless power receiver apparatus of claim 5, wherein the switch comprises a transistor.

7. The wireless power receiver apparatus of claim 5, wherein the adjustment circuit is configure to close the switch to cause a short.

8. The wireless power receiver apparatus of claim 1, wherein the detectable change in the operating characteristic of the transmitter device comprises an increase in supply current to a driver circuit.

9. The wireless power receiver apparatus of claim 8, wherein the transmitter device is configured to wirelessly output power at the second power level when the increase in supply current is above a threshold.

10. A method for wirelessly receiving power, the method comprising:

wirelessly receiving power from a transmitter device at a first power level or a second power level to power a load, wherein the first power level is lower than the second power level and corresponds to a low power mode of the transmitter device;

adjusting an operating characteristic of the load using the wirelessly received power during a period of time to cause a detectable change in an operating characteristic of the transmitter device for the period of time.

11. The method of claim 10, wherein wirelessly receiving power from the transmitter device comprises wirelessly receiving power at the second power level in response to the change in the operating characteristic of the transmitter device.

12. The method of claim 10, wherein the characteristic of the load comprises an impedance of the load.

13. The method of claim 12, wherein adjusting the operating characteristic comprises lowering the impedance of the load.

14. The method of claim 10, wherein adjusting the operating characteristic comprises altering a position of a switch.

15. The method of claim 14, wherein adjusting comprises closing the switch to cause a short.

16. The method of claim 10, wherein the detectable change in the operating characteristic of the transmitter device comprises an increase in supply current to a driver circuit.

17. The method of claim 16, wherein the transmitter device is configured to wirelessly output power at the second level when the increase in supply current is above a threshold.

18. A wireless power receiver apparatus, comprising:

means for wirelessly receiving power, the means for wirelessly receiving power being coupled to a load, the means for wirelessly receiving power being configured to wirelessly receive power from a means for wirelessly transmitting power at a first power level or a second power level to power the load, wherein the first power level is lower than the second power level and corresponds to a low power mode of the means for wirelessly transmitting power; and

means for adjusting configured to be powered by using the wirelessly received power, the means for adjusting being further configured to adjust a characteristic of the load using the wirelessly received power for a period of time to cause a detectable change in an operating characteristic of the means for wirelessly transmitting for the period of time.

19. The wireless power receiver apparatus of claim 18, wherein the means for wirelessly receiving is configured to wirelessly receive power from the means for wirelessly transmitting at the second power level in response to the change in the operating characteristic of the means for wirelessly transmitting.

20. The wireless power receiver apparatus of claim 18, wherein the characteristic of the load comprises an impedance of the load.

21. The wireless power receiver apparatus of claim 20, wherein the means for adjusting is configured to lower the impedance of the load.

22. The wireless power receiver apparatus of claim 18, wherein the means for adjusting further comprising a means for switching, wherein the means for adjusting is configured to adjust a characteristic of the load by altering a position of the means for switching.

23. The wireless power receiver apparatus of claim 22, wherein the means for switching comprises a transistor.

24. The wireless power receiver apparatus of claim 22, wherein the means for adjusting is configure to close the means for switching to cause a short.

25. The wireless power receiver apparatus of claim 18, wherein the first power level corresponds to a low power mode of the means for wirelessly transmitting.

26. The wireless power receiver apparatus of claim 18, wherein the detectable change in the operating characteristic of the means for wirelessly transmitting comprises an increase in supply current to a driver circuit.

27. The wireless power receiver apparatus of claim 26, wherein the means for wirelessly transmitting is configured to wirelessly output power at the second level when the increase in supply current is above a threshold.

28. The wireless power receiver apparatus of claim 18, wherein the means for wirelessly receiving power comprises a receive circuit comprising a receive coil.

29. The wireless power receiver apparatus of claim 18, wherein the means for adjusting comprises an adjustment circuit.

30. The wireless power receiver apparatus of claim 18, wherein the means for wirelessly transmitting comprises a transmit circuit comprising a transmit coil.