NFC transceiver utilizing common circuitry for active and passive modes

• US 8,818,267 B2
• Filed: 10/26/2011
• Issued: 08/26/2014
• Est. Priority Date: 10/26/2011
• Status: Expired due to Fees

• Current Assignee: Qualcomm, Inc.
• Original Assignee: Qualcomm, Inc.
• Inventors: Savoj, Jafar
• Primary Examiner(s): Alam, Fayyaz
• Assistant Examiner(s): Mathew, Max
• Application Number:
  US13/282,359
• Publication Number:
  US 20130109306A1
• Time in Patent Office: 1,035 Days
• Field of Search: 455/41.1, 323/269, 323/273, 323/274, 323/281, 323/282, 323/303
• US Class Current: 455/41.1
• CPC Class Codes: G06K 7/10237 the reader and the record carrier being capable of selectively switching between reader and record carrier appearance, e.g. in near field communication [NFC] devices where the NFC device may function as an RFID reader or as an RFID tag
• CPC Class Codes: H04B 5/22 Capacitive coupling
• CPC Class Codes: H04B 5/77 for interrogation
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

Exemplary embodiments are directed to a transceiver. A transceiver may include a rectifier coupled to a capacitor. The transceiver may further include a power management module coupled to the capacitor, wherein the capacitor is configured as a power supply capacitor in a first mode and a rectifier capacitor in a second, different mode.

Claims

1. A transceiver, comprising:

a rectifier coupled to a capacitor;

a power management module coupled to the capacitor;

wherein the capacitor is configured as a power supply capacitor in a first mode and a rectifier capacitor in a second, different mode.

2. The transceiver of claim 1, the power management module comprising a power management integrated circuit (PMIC).

3. The transceiver of claim 1, the capacitor configured as the rectifier capacitor in a passive mode and the power supply capacitor in an active mode.

4. The transceiver of claim 1, further comprising a pad coupling the capacitor to an integrated circuit including the rectifier.

5. The transceiver of claim 4, further comprising a pad coupling each of the power management module and the capacitor to an integrated circuit including the rectifier.

6. The transceiver of claim 1, further comprising a switching element configured to be in a closed configuration in the first mode and an open configuration in the second mode.

7. The transceiver of claim 1, the capacitor configured as a filter in an active mode and configured to store charge in a passive mode.

8. A Near Field Communication (NFC) transceiver, comprising:

a capacitor;

a rectifier coupled to the capacitor; and

a power management module coupled to the capacitor, each of the capacitor, the rectifier and the power management module coupled to a switching element for selectively configuring the NFC transceiver for operation in either an active mode or a passive mode.

9. The NFC transceiver of claim 8, the power management module comprising a PMIC.

10. The NFC transceiver of claim 8, the capacitor configured as a filter in the active mode and configured to store charge in the passive mode.

11. The NFC transceiver of claim 8, each of the capacitor and the power management module external to an integrated circuit including the rectifier.

12. The NFC transceiver of claim 11, further comprising a pad for coupling each of the power management module and the capacitor to the integrated circuit.

13. The NFC transceiver of claim 8, the switching element configured to couple the capacitor to NFC circuitry while bypassing a regulator in the active mode.

14. A method, comprising:

storing a charge with a capacitor while in a passive NFC mode; and

filtering with the capacitor while in an active NFC mode.

15. The method of claim 14, the filtering comprising filtering noise with the capacitor while in the active mode.

16. The method of claim 14, further comprising conveying energy to the capacitor via a pad in the passive mode and conveying energy from a power management module to NFC circuitry via the pad in the active mode.

17. The method of claim 14, further comprising closing a switching element to operate in the active mode.

18. The method of claim 14, further comprising opening a switching element to operate in the passive mode.

19. A method, comprising:

conveying energy from an antenna to a capacitor via a contact pad in a first NFC mode; and

conveying energy from a power management module to NFC circuitry from the capacitor via the contact pad in a second NFC mode.

20. The method of claim 19, the conveying energy from an antenna to a capacitor comprising opening a switching element coupled to the capacitor.

21. The method of claim 19, the conveying energy from a power management module to NFC circuitry comprising closing a switching element coupled to the capacitor.

22. A device, comprising:

means for storing a charge with a capacitor while in a passive NFC mode; and

means for filtering with the capacitor while in an active NFC mode.

23. The device of claim 22, further comprising means for conveying energy to the capacitor via a pad in the passive mode and conveying energy from a power management module to NFC circuitry via the pad in the active mode.

24. A device, comprising:

means for conveying energy from an antenna to a capacitor via a pad in a first NFC mode; and

means for conveying energy from a power management module to NFC circuitry from the capacitor via the pad in a second NFC mode.

25. The device of claim 24, further comprising:

means for opening a switching element to convey energy from the antenna to the capacitor; and

means for closing the switching element to convey energy from the power management module to the NFC circuitry.