Charging a chargeable power supply of a near field communication (NFC) enabled device from a radio frequency (RF) signal inductively coupled onto a magnetic field

• US 8,432,293 B2
• Filed: 01/19/2006
• Issued: 04/30/2013
• Est. Priority Date: 01/19/2005
• Status: Active Grant

• Current Assignee: NXP USA, Inc. (NXP Semiconductors NV)
• Original Assignee: Innovision Research & Technology PLC (Broadcom, Inc.)
• Inventors: Symons, Peter Robert
• Primary Examiner(s): Mehmood, Jennifer
• Assistant Examiner(s): GIRMA, FEKADESELASS
• Application Number:
  US11/795,434
• Publication Number:
  US 20080272889A1
• Time in Patent Office: 2,658 Days
• Field of Search: None
• US Class Current: 340/854.8
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/20 using microwaves or radio frequency waves
• CPC Class Codes: H02J 50/402 the two or more transmitting or the two or more receiving devices being integrated in the same unit, e.g. power mats with several coils or antennas with several sub-antennas
• CPC Class Codes: H02J 7/00034 Charger exchanging data with an electronic device, i.e. telephone, whose internal battery is under charge
• CPC Class Codes: H04B 5/48 Transceivers
• CPC Class Codes: H04B 5/72 for local intradevice communication
• CPC Class Codes: H04B 5/77 for interrogation
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

A NFC communicator or NFC communications enabled device (1 or 2 or 100a) has a data store (108) to store data, a coupler (17 or 32 or 102) to couple inductively with the magnetic field of a radio frequency signal and a signal generator (109) to supply a radio frequency signal to the coupler. A modulator (110) is provided to modulate a radio frequency signal in accordance with data and a demodulator (114) is provided to extract data from a modulated radio frequency signal inductively coupled to the coupler. A controller (107) enables the NFC communicator or NFC communications enabled device both to initiate near field radio frequency communication with another near field RF communicator and to respond to near field radio frequency communication initiated by another near field RF communicator. The NFC communicator or NFC communications enabled device also has a power deliver (19 or 34 or 103) that derives power from a radio frequency signal inductively coupled to the coupler to charge a chargeable power supply.

Claims

1. A near field communications (NFC) enabled device, comprising:

a first coupler configured to receive a first radio frequency (RF) signal inductively coupled onto a magnetic field;

operational components configured to demodulate the first RF signal to provide received data;

a second coupler configured to receive a second RF signal inductively coupled onto the magnetic field; and

a power deriver configured to charge a chargeable power supply based upon the second RF signal, the NFC enabled device being configured to allow charging only when the second RF signal includes a permission to charge.

2. The NFC enabled device of claim 1, wherein the power deriver comprises:

a rectifier configured to generate a rectified power output from the second RF signal; and

a charging unit configured to generate a charging power output based upon the rectified power output to charge the chargeable power supply.

3. The NFC enabled device of claim 2, wherein the charging unit comprises:

a switched mode power supply configured to generate the charging power output based upon the rectified power output; and

a power supply unit controller configured to cause the switched mode power supply to adjust the charging power output to ensure that it is sufficient to charge the chargeable power supply.

5. The NFC enabled device of claim 1, wherein the chargeable power supply comprises:

a battery having one or more cells.

6. The NFC enabled device of claim 1, wherein the first coupler is further configured to produce the magnetic field based upon a third RF signal.

7. The NFC enabled device of claim 6, wherein the operational components comprise:

a demodulator configured to demodulate the first RF signal to provide the received data; and

a modulator configured to modulate transmitted data to provide the third RF signal; and

a controller configured to control operation of the NFC enabled device.

8. The NFC enabled device of claim 7, wherein the controller is further configured to activate the power deriver upon receipt of instructions over the first RF signal.

9. The NFC enabled device of claim 7, wherein the controller is further configured to detect whether the first RF signal represents an unmodulated RF signal and to activate the power deriver upon detecting the first RF signal is the unmodulated RF signal.

10. The NFC enabled device of claim 7, wherein the first RF signal and the second RF signal are characterized by a first frequency and a second frequency, respectively, the first frequency being different from the second frequency, and wherein the controller is further configured to activate the power deriver upon detecting the second frequency.

11. The NFC enabled device of claim 1, wherein the operational components are further configured to demodulate the first RF signal simultaneously with charging of the chargeable power supply.

24. The NFC enabled device of claim 1, wherein the operational components comprise:

a controller configured to request, upon determination that the chargeable power supply requires charging, the permission from a second NFC enabled device that provides the second RF signal, wherein the controller only allows charging when the NFC enabled device receives the permission from the second NFC enabled device.

25. The NFC enabled device of claim 24, wherein the controller activates the power deriver to begin power derivation upon receipt of the permission.

4. The NFC enabled device of 2, wherein the charging unit comprises:

a lineal regulator configured to generate the charging power output based upon the rectified power output; and

a power supply unit controller configured to cause the linear regulator to adjust the charging power output to ensure that it is sufficient to charge the chargeable power supply.

12. A near field communications (NFC) enabled device, comprising:

a demodulator configured to demodulate a first radio frequency (RF) signal that is inductively coupled onto a magnetic field by a second NFC enabled device; and

a power deriver configured to charge a chargeable power supply based upon a second RF signal that is inductively coupled onto the magnetic field by the second NFC enabled device, the NFC enabled device being configured to allow charging only when the second RF signal includes a permission to charge,

wherein the first RF signal and the second RF signal are characterized by a first frequency and a second frequency, respectively, the first frequency being different from the second frequency.

13. The NFC enabled device of claim 12, further comprising:

a first coupler configured to receive the first RF signal; and

a second coupler configured to receive the second RF signal.

14. The NFC enabled device of claim 12, wherein the demodulator is further configured to demodulate the first RF signal simultaneously with charging of the chargeable power supply.

15. A near field communications (NFC) enabled device, comprising:

means for receiving a first radio frequency (RF) signal inductively coupled onto a magnetic field;

means for demodulating the first RF signal to provide received data;

means for receiving a second RF signal inductively coupled onto the magnetic field; and

means for charging a chargeable power supply based upon the second RF signal, the NFC enabled device being configured to allow charging only when the second RF signal includes a permission to charge.

16. The NFC enabled device of claim 15, wherein the means for charging comprises:

means for generating a rectified power output from the second RF signal; and

means for generating a charging power output based upon the rectified power output to charge the chargeable power supply.

17. The NFC enabled device of claim 16, wherein the means for generating the charging power output comprises:

means for generating a switched mode power output as the charging power output based upon the rectified power output; and

means for adjusting the switched mode power output to ensure that it is sufficient to charge the chargeable power supply.

18. The NFC enabled device of claim 15, wherein the chargeable power supply comprises:

means for storing power using one or more cells.

19. The NFC enabled device of claim 15, wherein the means for receiving the first RF signal further comprises:

means for producing the magnetic field based upon a third RF signal.

20. The NFC enabled device of claim 19, further comprising:

means for modulating transmitted data to provide the third RF signal; and

means for controlling operation of the NFC enabled device.

21. The NFC enabled device of claim 20, wherein the means for controlling operation comprises:

means for activating the means for charging upon receipt of instructions over the first RF signal.

22. The NFC enabled device of claim 20, wherein the means for controlling operation comprises:

means for detecting whether the first RF signal represents an unmodulated RF signal and to activate the means for charging upon detecting the first RF signal is the unmodulated RF signal.

23. The NFC enabled device of claim 20, wherein the first RF signal and the second RF signal are characterized by a first frequency and a second frequency, respectively, the first frequency being different from the second frequency, and wherein the means for controlling operation comprises:

means for activating the means for charging upon detecting the second frequency.