WAKING UP A WIRELESS POWER TRANSMITTER FROM BEACON MODE

• US 20120223589A1
• Filed: 01/17/2012
• Published: 09/06/2012
• Est. Priority Date: 03/01/2011
• Status: Active Grant

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Low, Zhen Ning, Lee, Kevin Douglas
• Granted Patent: US 9,306,634 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 50/40 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 to power the load; 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 a second power level in response to the change in the operating characteristic of the transmitter device, the second power level being higher than the first power level.

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 a 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 first power level corresponds to a low power mode of the transmitter device.

9. 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.

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

11. A method for waking a wireless power transmitter from a low power mode, the method comprising:

wirelessly receiving power from a transmitter device at a first power level to power a load;

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.

12. The method of claim 11, further comprising wirelessly receiving power from the transmitter device at a second power level in response to the change in the operating characteristic of the transmitter device, the second power level being higher than the first power level.

13. The method of claim 11, wherein the characteristic of the load comprises an impedance of the load.

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

15. The method of claim 11, wherein adjusting the operating characteristic comprises altering a position of a switch.

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

17. The method of claim 11, wherein the first power level corresponds to a low power mode of the transmitter device.

18. The method of claim 11, wherein the detectable change in the operating characteristic of the transmitter device comprises an increase in supply current to a driver circuit.

19. The method of claim 18, wherein the transmitter device is configured to wirelessly output power at the second level when the increase in supply current is above a threshold.

20. 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 to power the load; 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.

21. The wireless power receiver apparatus of claim 20, wherein the means for wirelessly receiving is configured to wirelessly receive power from the means for wirelessly transmitting at a second power level in response to the change in the operating characteristic of the means for wirelessly transmitting, the second power level being higher than the first power level.

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

23. The wireless power receiver apparatus of claim 22, wherein the means for adjusting is configured to lower the impedance of the load.

24. The wireless power receiver apparatus of claim 20, 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.

25. The wireless power receiver apparatus of claim 24, wherein the means for switching comprises a transistor.

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

27. The wireless power receiver apparatus of claim 20, wherein the first power level corresponds to a low power mode of the means for wirelessly transmitting.

28. The wireless power receiver apparatus of claim 20, wherein the detectable change in the operating characteristic of the means for wirelessly transmitting comprises an increase in supply current to a driver circuit.

29. The wireless power receiver apparatus of claim 28, 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.

30. The wireless power receiver apparatus of claim 20, wherein the means for wirelessly receiving power comprises a receive circuit comprising a receive coil.

31. The wireless power receiver apparatus of claim 20, wherein the means for adjusting comprises an adjustment circuit.

32. wireless power receiver apparatus of claim 20, wherein the means for wirelessly transmitting comprises a transmit circuit comprising a transmit coil.

33. A wireless power transmitter apparatus, comprising:

a transmit circuit comprising a transmit coil, the transmit circuit being configured to wirelessly transmit power at a first level so as to charge or power a receiver device; and

a transmit controller circuit configured cause the transmit circuit to wirelessly transmit power at a second level in response to a detected change in an operating characteristic based on an action of the receiver device, the second power level being higher than the first power level.

34. The wireless power transmitter apparatus of claim 33, wherein the first power level corresponds to a low power mode.

35. The wireless power transmitter apparatus of claim 33, further comprising a driver circuit configured to drive the transmit coil with a signal having a duty cycle of substantially twenty percent or less.

36. The wireless power transmitter apparatus of claim 33, wherein the transmit circuit further comprises a driver circuit, and wherein the detected change in the operating characteristic corresponds to an increase in a supply current level to the driver circuit.

37. The wireless power transmitter apparatus of claim 36, wherein the transmit controller circuit is configured to cause the transmit circuit to wirelessly transmit power at the second power level if the increase in the supply current level is above a threshold.

38. A method for waking from a low power mode, comprising:

wirelessly transmitting power a first power level for a determined period of time so as to power or charge a receiver device;

detecting a change in an operating characteristic based on an action of the receiver device; and

wirelessly transmitting power at a second power level in response to the detected change, the second power level being higher than the first power level.

39. The method of claim 38, wherein the first power level corresponds to a low power mode.

40. The method of claim 38, further comprising driving a transmit coil for wirelessly transmitting power with a signal having a duty cycle of substantially twenty percent or less.

41. The method of claim 38, further comprising detecting an increase in a supply current level to a driver circuit.

42. The method of claim 41, wherein wirelessly transmitting power at a second power level comprises wirelessly transmitting power at the second power level if the increase in the supply current level is above a threshold.

43. A wireless power transmitter apparatus, comprising:

means for wirelessly transmitting power being configured to wirelessly transmit power at a first level for a determined period of time so as to power or charge a means for wirelessly receiving power; and

means for controlling configured to cause the means for wirelessly transmitting power to wirelessly transmit power at a second level in response to a detected change in an operating characteristic based on an action of the means for wirelessly receiving power, the second power level being higher than the first power level.

44. The wireless power transmitter apparatus of claim 43, wherein the first power level corresponds to a low power mode.

45. The wireless power transmitter apparatus of claim 43, further comprising a means for driving configured to drive the means for wirelessly transmitting power with a signal having a twenty cycle of substantially ten percent or less.

46. The wireless power transmitter apparatus of claim 43, wherein the means for wirelessly transmitting power further comprises a means for driving, and wherein the detected change in the operating characteristic corresponds to an increase in a supply current level to the means for driving.

48. The wireless power transmitter apparatus of claim 43, wherein the means for wirelessly transmitting power comprises a transmit circuit comprising a transmit coil.

49. The wireless power transmitter apparatus of claim 43, wherein the means for controlling comprises a transmit controller circuit.

50. The wireless power transmitter apparatus of claim 43, wherein the means for wirelessly receiving power comprises a receive circuit comprising a receive coil.

47. The wireless power transmitter apparatus of claim 47, wherein the means for controlling is configured to cause the means for wirelessly transmitting power to wirelessly transmit power at the second power level if the increase in the supply current level is above a threshold.