MOBILE WIRELESS COMMUNICATIONS DEVICE WITH NFC COUPLING CIRCUIT AND RELATED METHODS

• US 20140220889A1
• Filed: 04/08/2014
• Published: 08/07/2014
• Est. Priority Date: 01/06/2012
• Status: Active Grant

• Current Assignee: Malikie Innovations Limited (Key Patent Innovations Limited)
• Original Assignee: Blackberry Limited
• Inventors: ZHU, LIZHONG, ZHU, LIBO
• Granted Patent: US 9,014,734 B2
• Time in Patent Office: Days
• US Class Current: 455/41.1
• CPC Class Codes: H04B 5/00 Near-field transmission systems, e.g. inductive or capacitive transmission systems
• CPC Class Codes: H04B 5/22 Capacitive coupling
• CPC Class Codes: H04M 1/72412 using two-way short-range wireless interfaces
• CPC Class Codes: H04M 2250/04 including near field communication means, e.g. RFID
• CPC Class Codes: Y10T 29/49018 with other electrical component

Abstract

A mobile wireless communications device may include a housing, a wireless transceiver carried by the housing, a processor carried by the housing and coupled to the wireless transceiver, and an NFC IC carried by the housing and coupled to the processor. The mobile wireless communications device may also include an NFC antenna carried by the housing, and a coupling circuit between the NFC IC and the NFC antenna. The coupling circuit may include a capacitive network including capacitors coupled in series with each other and in parallel with the NFC antenna, a transmit branch coupled between the NFC IC and a first node between a first pair of capacitors, and a receive branch coupled between the NFC IC and the first node between the first pair of capacitors.

Claims

1-22. -22. (canceled)

23. An electronic comprising:

a near field communication (NFC) antenna;

an NFC circuit;

a capacitive network comprising a plurality of capacitors coupled in series with each other and in parallel with said NFC antenna;

a transmit branch coupled between said NFC circuit and a first node between a first pair of capacitors of said plurality thereof; and

a receive branch coupled between said NFC circuit and the first node between the first pair of capacitors of said plurality thereof.

24. The electronic device of claim 23 further comprising at least one tuning branch coupled between said NFC circuit and a second node between a second pair of capacitors of said plurality thereof.

25. The electronic device of claim 24 wherein said at least one tuning branch comprises a pair thereof.

26. The electronic device of claim 25 wherein said pair of tuning branches comprises a first tuning branch comprising a first capacitor, and a second tuning branch comprising a second capacitor, and a diode coupled thereto.

27. The electronic device of claim 23 wherein said transmit branch comprises an inductor and a capacitor coupled thereto.

28. The electronic device of claim 27 wherein said transmit branch further comprises another capacitor coupled at a node between said inductor and said capacitor and a voltage reference.

29. The electronic device of claim 23 wherein said receive branch comprises a resistor and a capacitor coupled thereto.

30. The electronic device of claim 23 wherein said NFC circuit is configured to operate in an IC card emulation mode or a reader/writer mode.

31. A electronic device comprising:

a near field communication (NFC) antenna;

an NFC circuit configured to operate in an IC card emulation mode or a reader/writer mode;

a capacitive network comprising a plurality of capacitors coupled in series with each other and in parallel with said NFC antenna;

a transmit branch coupled between said NFC circuit and a first node between a first pair of capacitors of said plurality thereof;

a receive branch coupled between said NFC circuit and the first node between the first pair of capacitors of said plurality thereof; and

at least one tuning branch coupled between said NFC circuit and a second node between a second pair of capacitors of said plurality thereof.

32. The electronic device of claim 31 wherein said at least one tuning branch comprises a pair thereof.

33. The electronic device of claim 32 wherein said pair of tuning branches comprises a first tuning branch comprising a first capacitor, and a second tuning branch comprising a second capacitor, and a diode coupled thereto.

34. The electronic device of claim 31 wherein said transmit branch comprises an inductor and a capacitor coupled thereto.

35. The electronic device of claim 34 wherein said transmit branch further comprises another capacitor coupled at a node between said inductor and said capacitor and a voltage reference.

36. The electronic device of claim 31 wherein said receive branch comprises a resistor and a capacitor coupled thereto.

37. A method for making an electronic device comprising a near field communication (NFC) antenna and an NFC circuit, the method comprising:

coupling the NFC circuit and the NFC antenna together using a capacitive network comprising a plurality of capacitors in series with each other and in parallel with the NFC antenna by at least

coupling a transmit branch between the NFC circuit and a first node between a first pair of capacitors of the plurality thereof, and

coupling a receive branch between the NFC circuit and the first node between the first pair of capacitors of the plurality thereof.

38. The method of claim 37 further comprising coupling at least one tuning branch between the NFC circuit and a second node between a second pair of capacitors of the plurality thereof.

39. The method of claim 38 wherein the at least one tuning branch comprises a pair thereof.

40. The method of claim 39 wherein the pair of tuning branches comprises a first tuning branch comprising a first capacitor, and a second tuning branch comprising a second capacitor, and a diode coupled thereto.

41. The method of claim 37 wherein the transmit branch comprises an inductor and a capacitor coupled thereto.

42. The method of claim 41 wherein the transmit branch further comprises another capacitor coupled at a node between the inductor and the capacitor and a voltage reference.