Radio frequency data communications device

• US 6,771,613 B1
• Filed: 09/23/1998
• Issued: 08/03/2004
• Est. Priority Date: 05/13/1996
• Status: Expired due to Fees

• Current Assignee: Round Rock Research LLC
• Original Assignee: Micron Technology, Inc.
• Inventors: Ovard, David K., Tuttle, John R., Rotzoll, Robert R., Tuttle, Mark E., Lowrey, Tyler, Higgins, Brian P., Yu, Shu-Sun, Devereaux, Kevin M., Pax, George E., OʼToole, James E.
• Primary Examiner(s): HOLLOWAY III, EDWIN C
• Application Number:
  US09/159,425
• Time in Patent Office: 2,141 Days
• Field of Search: 370/277, 370/310, 340/825.54, 340/10.4, 342/44, 342/51, 285/385, 381/68.6
• US Class Current: 370/277
• CPC Class Codes: G06K 19/0707 the arrangement being capable of collecting energy from external energy sources, e.g. thermocouples, vibration, electromagnetic radiation G06K19/0702 takes precedence
• CPC Class Codes: G06K 19/0712 the arrangement being capable of triggering distinct operating modes or functions dependent on the strength of an energy or interrogation field in the proximity of the record carrier active means for hindering electromagnetic reading or writing G06K19/07336
• CPC Class Codes: G06K 19/0716 at least one of the integrated circuit chips comprising a sensor or an interface to a sensor
• 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 19/07749 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 19/07758 arrangements for adhering the record carrier to further objects or living beings, functioning as an identification tag
• CPC Class Codes: G06K 7/0008 General problems related to the reading of electronic memory record carriers, independent of its reading method, e.g. power transfer
• CPC Class Codes: G06K 7/10059 transponder driven
• CPC Class Codes: H01Q 1/2225 used in active tags, i.e. provided with its own power source or in passive tags, i.e. deriving power from RF signal
• CPC Class Codes: H03L 7/0995 the oscillator comprising a ring oscillator
• CPC Class Codes: H03L 7/148 said digital means comprising a counter or a divider

Abstract

A radio frequency identification device comprises an integrated circuit including a receiver, a transmitter, and a microprocessor. The receiver and transmitter together define an active transponder. The integrated circuit is preferably a monolithic single die integrated circuit including the receiver, the transmitter, and the microprocessor. Because the device includes an active transponder, instead of a transponder which relies on magnetic coupling for power, the device has a much greater range.

Claims

1. An integrated circuit comprising:

a die including a transmitter having an antenna output and a detector having an antenna input;

a package housing the die;

a first contact directly electrically connected to the antenna output and accessible from outside the package;

a second contact directly electrically connected to the antenna input and accessible from outside the package; and

a short electrically connecting the first contact to the second contact outside the package.

2. A method of using an integrated circuit including a die having a transmitter including an antenna output and a detector including an antenna output, the integrated circuit further including a package housing the die, a first contact directly electrically connected to the antenna output and accessible from outside the package, and a second contact directly electrically connected to the antenna input and accessible from outside the package, the method comprising:

electrically shorting the first contact to the second contact outside the package.

3. A transceiver comprising:

a loop antenna having a first end connected to a bias voltage, and having a second end;

a detector including a Schottky diode having an anode connected to the second end of the antenna; and

an active transmitter having an output connected to the second end of the antenna.

4. A transceiver in accordance with claim 3 wherein the Schottky diode has a cathode, and further comprising a current source configured to direct current from the anode to the cathode.

5. A transceiver in accordance with claim 3 wherein the detector and transmitter do not operate simultaneously.

6. A transceiver in accordance with claim 3 wherein the Schottky diode has a cathode, and wherein the detector and transmitter do not operate simultaneously, the transceiver further comprising a current source configured to direct current from the anode to the cathode, and a pullup transistor connected to the cathode and configured to connect the cathode to the bias voltage when the transmitter is operating.

7. A transceiver comprising:

a loop antenna having a first end connected to a bias voltage, and having a second end;

a second antenna;

a detector including a Schottky diode having an anode connected to the second end of the antenna; and

a transmitter having an output connected to the second antenna.

8. A transceiver in accordance with claim 7 wherein the Schottky diode has a cathode, and further comprising a current source configured to direct current from the anode to the cathode.

9. A transceiver in accordance with claim 7 wherein the detector and transmitter do not operate simultaneously.

10. A transceiver comprising:

an antenna having a first end connected to a bias voltage, and having a second end;

a detector including a Schottky diode having an anode connected to the second end of the antenna; and

an active transmitter having an output connected to the second end of the antenna.

11. A transceiver in accordance with claim 10 wherein the Schottky diode has a cathode, and further comprising a current source configured to direct current from the anode to the cathode.

12. A transceiver in accordance with claim 10 wherein the detector and transmitter do not operate simultaneously.

13. A transceiver in accordance with claim 10 wherein the Schottky diode has a cathode, and wherein the detector and transmitter do not operate simultaneously, the transceiver further comprising a current source configured to direct current from the anode to the cathode, and a pullup transistor connected to the cathode and configured to connect the cathode to the bias voltage when the transmitter is operating.

14. A transceiver comprising:

a loop antenna having a first end, and having a second end;

a detector including a Schottky diode having a cathode connected to the second end of the antenna and defining a potential at the second end of the antenna, the first end of the antenna being connected to a potential lower than the potential of the second end of the antenna; and

a backscatter transmitter including a transistor having a first power electrode connected to the first end of the antenna, a second power electrode connected to the second end of the antenna, and a control electrode adapted to have a modulation signal applied thereto.

15. A transceiver in accordance with claim 14 and further comprising a current source configured to direct current from the anode to the cathode.

16. A transceiver in accordance with claim 14 wherein the receiver and transmitter do not operate simultaneously.

17. A transceiver in accordance with claim 14 and further comprising an integrated circuit package housing the detector and transmitter, and wherein the antenna is external of the package.

18. A transceiver comprising:

a loop antenna having a first end connected to a bias voltage, and having a second end;

a detector including a Schottky diode having an anode connected to the second end of the antenna;

a backscatter transmitter having a first output and having a second output;

a capacitor connected between the first output and the first end of the antenna; and

a capacitor connected between the second output and the second end of the antenna.

19. A transceiver in accordance with claim 18 wherein the Schottky diode has a cathode, and further comprising a current source configured to direct current from the anode to the cathode.

20. A transceiver in accordance with claim 18 wherein the receiver and transmitter do not operate simultaneously.

21. A transceiver in accordance with claim 18 and further comprising an integrated circuit package housing the detector and transmitter, and wherein the first and second capacitors are external of the package.

22. A method of configuring a transceiver including a backscatter transmitter having first and second outputs, and a detector having a Schottky diode including an anode, the method comprising:

applying a bias voltage to a first end of a loop antenna;

connecting a second end of the antenna to the anode;

connecting a first capacitor between the first output and the first end of the antenna; and

connecting a second capacitor between the second output and the second end of the antenna.

23. A method in accordance with claim 22 wherein the Schottky diode has a cathode, and further comprising directing current from the anode to the cathode.

24. A method in accordance with claim 22 wherein the receiver and transmitter do not operate simultaneously.

25. A method in accordance with claim 22 and further comprising housing the detector and transmitter in an integrated circuit package, and connecting the first and second capacitors external of the package.

26. A method of arranging a transceiver including a backscatter transmitter and a detector having a Schottky diode including a cathode, the method comprising:

coupling a first end of a loop antenna to a ground potential;

coupling a second end of the antenna to the cathode;

coupling a first power electrode of a transistor to the first end of the antenna;

coupling a second power electrode of the transistor to the second end of the antenna; and

coupling a control electrode of the transistor to a modulation signal.

27. A method in accordance with claim 26 and further comprising directing current from the anode to the cathode using a current source.

28. A method in accordance with claim 26 wherein the receiver and transmitter do not operate simultaneously.

29. A method in accordance with claim 26 and further comprising housing the detector and transmitter in an integrated circuit package, and locating the antenna external of the package.

30. A radio frequency identification device comprising:

an integrated circuit including both a receiver and a transmitter;

a first antenna connected to the receiver; and

a second antenna connected to the transmitter wherein the receiver includes a Schottky diode having a cathode and an anode, and further comprising a current source configured to direct current from the anode to the cathode, the current from the current source being set to achieve a selected diode impedance and thus a desired receiver sensitivity.

31. A radio frequency identification device comprising:

an integrated circuit including both a receiver and a transmitter;

a first antenna connected to the receiver; and

a second antenna connected to the transmitter wherein the receiver includes a Schottky diode having a cathode and an anode, and further comprising a current source configured to direct current from the anode to the cathode, the current from the current source being set to achieve a selected diode impedance and thus a desired receiver sensitivity, wherein the receiver and transmitter do not operate simultaneously.

32. A monolithic integrated circuit comprising:

a die including a transmitter having an antenna output and a detector having an antenna input;

a package housing the die;

a first contact directly electrically connected to the antenna output and accessible from outside the package;

a second contact directly electrically connected to the antenna input and accessible from outside the package; and

a short electrically connecting the first contact to the second contact outside the package.

33. A method of using a monolithic integrated circuit including a die having a transmitter including an antenna output and a detector including an antenna output, the integrated circuit further including a package housing the die, a first contact directly electrically connected to the antenna output and accessible from outside the package, and a second contact directly electrically connected to the antenna input and accessible from outside the package, the method comprising:

electrically shorting the first contact to the second contact outside the package.

34. A transceiver comprising:

a loop antenna having a first end connected to a bias voltage, and having a second end;

a separate second antenna;

a detector including a Schottky diode having an anode connected to the second end of the antenna; and

a transmitter having an output connected to the separate second antenna.

35. A transceiver in accordance with claim 34 wherein the Schottky diode has a cathode, and further comprising a current source configured to direct current from the anode to the cathode.

36. A transceiver in accordance with claim 34 wherein the detector and transmitter do not operate simultaneously.

37. A radio frequency identification device comprising:

an integrated circuit including both a receiver and a transmitter;

a first antenna connected to the receiver; and

a separate second antenna connected to the transmitter wherein the receiver includes a Schottky diode having a cathode and an anode, and further comprising a current source configured to direct current from the anode to the cathode, the current from the current source being set to achieve a selected diode impedance and thus a desired receiver sensitivity.

38. A radio frequency identification device comprising:

an integrated circuit including both a receiver and a transmitter;

a first antenna connected to the receiver; and

a separate second antenna connected to the transmitter wherein the receiver includes a Schottky diode having a cathode and an anode, and further comprising a current source configured to direct current from the anode to the cathode, the current from the current source being set to achieve a selected diode impedance and thus a desired receiver sensitivity, wherein the receiver and transmitter do not operate simultaneously.