RADIO FREQUENCY IDENTIFICATION TAG

• US 20100277282A1
• Filed: 06/29/2009
• Published: 11/04/2010
• Est. Priority Date: 04/30/2009
• Status: Abandoned Application

• Current Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Original Assignee: Hynix Semiconductor Incorporated (SK Hynix Inc.)
• Inventors: Kang, Hee-Bok
• Application Number:
  US12/493,518
• Publication Number:
  US 20100277282A1
• Time in Patent Office: Days
• US Class Current: 340/10.1
• CPC Class Codes: H02J 50/05 using capacitive coupling
• 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 7/0068 Battery or charger load switching, e.g. concurrent charging and load supply H02J7/0013 takes precedence
• CPC Class Codes: H04B 5/77 for interrogation
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

A radio frequency identification (RFID) tag includes an RFID block; a battery; and a control unit configured to control to supply an internal power for use in the RFID block by using a radio frequency (RF) signal or by using a battery voltage, which is a voltage of the battery.

Claims

1. A radio frequency identification (RFID) tag, comprising:

an RFID block;

a battery; and

a control unit configured to control to supply an internal power for use in the RFID block by using a radio frequency (RF) signal or by using a battery voltage, which is a voltage of the battery.

2. The RFID tag of claim 1, wherein the control unit includes:

a radio frequency voltage detection circuit configured to detect a voltage level of an RF voltage generated from the RF signal received from an exterior and output a plurality of selection signals corresponding to the voltage level of the RF voltage;

a first switch configured to receive a first selection signal among the plurality of the selection signals and supply the RF voltage as the internal power in response to the first selection signal; and

a second switch configured to receive a second selection signal among the plurality of the selection signals and the battery voltage as the internal power in response to the second selection signal.

3. The RFID tag of claim 2, wherein the control unit further includes:

a third switch configured to receive a third selection signal among the plurality of the selection signals and charge the battery by using the RF voltage in response to the third selection signal; and

a fourth switch configured to receive a fourth selection signal among the plurality of the selection signals and regulate the voltage level of the RF voltage in response to the fourth selection signal.

4. The RFID tag of claim 1, wherein the RFID block includes:

an analog block configured to generate a power signal and internal processing signals by using an analog signal from an antenna;

a digital block configured to receive the power signal and the internal processing signals from the analog block and perform digital operations; and

a memory block configured to store data under control of the digital block.

5. The RFID tag of claim 4, wherein the analog block includes:

a voltage multiplier configured to generate the RF voltage by using the RF signal from the antenna;

a demodulator configured to generate internal processing signals based on the RF signal from the antenna and output the internal processing signals to the digital block;

a modulator configured to modulate a response signal transmitted from the digital block and transmit the modulated signal to the antenna;

a power-on reset unit configured to receive the power signal and output a power-on reset signal to the digital block; and

a clock generating unit configured to receive the power signal and output a clock signal to the digital block.

6. The RFID tag of claim 2, wherein the control unit determines an operation mode of the RFID block and supplies the corresponding internal power with the RFID block, and the operation mode includes a battery-power activation mode in which the battery is used voltage as the internal power, an RF-power activation mode in which the RF voltage is used as the internal power, a battery charging mode in which the battery is charged by using the RF voltage, and a voltage regulation mode in which a voltage level of the RF voltage is maintained.

7. The RFID tag of claim 6, wherein the control unit determines the operation mode of the RFID block as the battery-power activation mode, the RF-power activation mode, the battery charging mode and the voltage regulation mode in sequence, as the voltage level of the RF voltage increases.

8. The RFID tag of claim 2, wherein the RF voltage detection circuit includes:

a reference voltage generating unit configured to generate a reference voltage;

a comparison voltage generating unit configured to generate a comparison voltage;

an RF voltage comparing unit configured to compare the reference voltage and the comparison voltage; and

an output unit configured to output a comparison result in the RF voltage comparing unit.

9. The RFID tag of claim 8, wherein the RF voltage comparison unit includes a differential amplifier.

10. A radio frequency identification (RFID) tag, comprising:

an RFID block;

a battery;

a voltage multiplier configured to generate a radio frequency (RF) voltage by using an RF signal received from an exterior;

an RF voltage detection circuit configured to detect a voltage level of the RF voltage; and

an internal voltage control circuit configured to control to supply the RF voltage or a battery voltage, which is a voltage of the battery, as an internal power with the RFID block according to a detection result of the RF voltage detection circuit.

11. The RFID tag of claim 10, wherein the internal voltage control circuit includes:

a switch control driving unit configured to generate first to fourth selection signals according to the detection result of the RF voltage detection circuit;

a first switch configured to receive the first selection signal and supply the RF voltage as the internal power; and

a second switch configured to receive the second selection signal and supply the battery voltage as the internal power.

12. The RFID tag of claim 11, wherein the internal voltage control circuit further includes:

a third switch configured to receive the third selection signal and charge the battery with the RF voltage; and

a fourth switch configured to receive the fourth selection signal and regulate the voltage level of the RF voltage.

13. The RFID tag of claim 10, wherein the RFID block includes:

an analog block configured to generate a power signal and internal processing signals by using an analog signal from an antenna;

a digital block configured to receive the power signal and the internal processing signals from the analog block and perform digital operations; and

a memory block configured to store data under control of the digital block.

14. The RFID tag of claim 13, wherein the analog block includes:

a voltage multiplier configured to generate the RF voltage by using the RF signal from the antenna;

a demodulator configured to generate internal processing signals based on the RF signal from the antenna and output the internal processing signals to the digital block;

a modulator configured to modulate a response signal RP transmitted from the digital block and transmit the modulated signal to the antenna;

a power-on reset unit configured to receive the power signal and output a power-on reset signal to the digital block; and

a clock generating unit configured to receive the power signal and output a clock signal to the digital block.

15. The RFID tag of claim 10, wherein the internal voltage control circuit determines an operation mode of the RFID block and supplies the corresponding internal power with the RFID block, and the operation mode includes a battery-power activation mode in which the battery is used voltage as the internal power, an RF-power activation mode in which the RF voltage is used as the internal power, a battery charging mode in which the battery is charged by using the RF voltage, and a voltage regulation mode in which a voltage level of the RF voltage is maintained.

16. The RFID tag of claim 15, wherein the internal voltage control circuit determines the operation mode of the RFID block as the battery-power activation mode, the RF-power activation mode, the battery charging mode and the voltage regulation mode in sequence, as the voltage level of the RF voltage increases.

17. The RFID tag of claim 10, wherein the RF voltage detection circuit includes:

a reference voltage generating unit configured to generate a reference voltage;

a comparison voltage generating unit configured to generate a comparison voltage;

an RF voltage comparing unit configured to compare the reference voltage and the comparison voltage; and

an output unit configured to output a comparison result in the RF voltage comparing unit.

18. The RFID tag of claim 10, wherein the RF voltage comparison unit includes a differential amplifier.