Active circuit for RFID

• US 8,866,614 B2
• Filed: 04/26/2013
• Issued: 10/21/2014
• Est. Priority Date: 08/08/2008
• Status: Active Grant

• Current Assignee: Icashe Incorporated
• Original Assignee: Tyfone Incorporated
• Inventors: Narendra, Siva G., Chakraborty, Saurav, Tadepalli, Prabhakar
• Primary Examiner(s): PHAM, TOAN NGOC
• Application Number:
  US13/871,849
• Publication Number:
  US 20130233931A1
• Time in Patent Office: 543 Days
• Field of Search: 340/572.1, 340/572.8, 340/10.1, 340/10.51, 235/492, 235/379, 235/380, 235/493, 705/1, 710/100, 710/301
• US Class Current: 340/572.1
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• CPC Class Codes: G06K 19/0715 the arrangement including means to regulate power transfer to the integrated circuit
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs
• CPC Class Codes: G06K 19/0726 the arrangement including a circuit for tuning the resonance frequency of an antenna on the record carrier
• CPC Class Codes: G06K 19/0727 the arrangement being a circuit facilitating integration of the record carrier with a hand-held device such as a smart phone of PDA
• CPC Class Codes: G06K 19/073 Special arrangements for circuits, e.g. for protecting identification code in memory protection against unauthorised use of computer memory G06F12/14
• CPC Class Codes: G06K 19/07732 the record carrier having a housing or construction similar to well-known portable memory devices, such as SD cards, USB or memory sticks housings for electrical equipment in general, see H05K5/02
• CPC Class Codes: G06K 19/07749 the record carrier being capable of non-contact communication, e.g. constructional details of the antenna of a non-contact smart card
• CPC Class Codes: G06K 19/07769 the further communication means being a galvanic interface, e.g. hybrid or mixed smart cards having a contact and a non-contact interface
• CPC Class Codes: G06Q 20/204 comprising interface for record bearing medium or carrier for electronic funds transfer or payment credit
• CPC Class Codes: G06Q 20/3278 RFID or NFC payments by means of M-devices
• CPC Class Codes: H04B 1/3816 Mechanical arrangements for accommodating identification devices, e.g. cards or chips; with connectors for programming identification devices
• CPC Class Codes: H04B 5/70 specially adapted for specific purposes
• CPC Class Codes: H04B 5/77 for interrogation
• CPC Class Codes: Y02D 30/70 in wireless communication networks

Abstract

An RFID card includes a smartcard controller that receives power from a host device. The RFID card also includes a small inductive device capable of inductive coupling with an RFID reader. The small inductive device is small enough to fit in the form factor of a memory card or SIM card. Enhancement circuits enhance the usable read and write distance of the RFID card.

Claims

1. A memory card comprising:

a smartcard controller coupled to receive power from a host device;

an amplifier to receive a signal from a receive antenna when the receive antenna is inductively coupled to another device, the amplifier providing a simplex communication path from the receive antenna to a contactless interface on the smartcard controller; and

a transmit circuit to receive outgoing data from the contactless interface and to drive a transmit antenna.

2. The memory card of claim 1 wherein the transmit antenna and receive antenna are one antenna.

3. The memory card of claim 1 wherein the transmit antenna and receive antenna are affixed to the memory card.

4. The memory card of claim 1 wherein the transmit antenna and receive antenna are external to the memory card, the memory card comprising contacts to couple to the transmit antenna and receive antenna.

5. The memory card of claim 1 further comprising an extraction circuit coupled between the contactless interface and the transmit circuit to extract and provide outgoing data to the transmit circuit.

6. The memory card of claim 1 wherein the smartcard controller includes a pad coupled to the transmit circuit to output data.

7. The memory card of claim 1 wherein the memory card comprises a microSD card.

8. A subscriber identity module (SIM) card comprising:

a smartcard controller coupled to receive power from a host device;

an amplifier to receive a signal from a receive antenna when the receive antenna is inductively coupled to another device, the amplifier providing a simplex communication path from the receive antenna to a contactless interface on the smartcard controller; and

a transmit circuit to receive outgoing data from the contactless interface and to drive a transmit antenna.

9. The SIM card of claim 8 wherein the transmit antenna and receive antenna are one antenna.

10. The SIM card of claim 8 wherein the transmit antenna and receive antenna are affixed to the SIM card.

11. The SIM card of claim 8 wherein the transmit antenna and receive antenna are external to the SIM card, the SIM card comprising contacts to couple to the transmit antenna and receive antenna.

12. The SIM card of claim 8 further comprising an extraction circuit coupled between the contactless interface and the transmit circuit to extract and provide outgoing data to the transmit circuit.

13. The SIM card of claim 8 wherein the smartcard controller includes a pad coupled to the transmit circuit to output data.

14. An apparatus comprising:

a smartcard controller having a contactless interface that includes two pads intended for connection to a coil, wherein the smartcard controller includes load modulation circuitry coupled to one of the two pads for half duplex communication when the coil is inductively coupled to a coil of a separate device;

a receive coil;

an amplifier coupled to receive a signal from the receive coil when the receive coil is inductively coupled, and to drive one of the two pads;

a transmit coil; and

a circuit coupled to one of the two pads to detect effects of the load modulation circuitry, and to drive a signal on to the transmit coil.

15. The apparatus of claim 14 wherein the transmit coil and receive coil are one coil.

16. The apparatus of claim 15 wherein the circuit coupled to one of the two pads to detect effects of the load modulation circuitry comprises outgoing data extraction circuitry.

17. The apparatus of claim 14 wherein the circuit coupled to one of the two pads to detect effects of the load modulation circuitry comprises outgoing data extraction circuitry.