Semiconductor device and IC label, IC tag, and IC card having the same

• US 8,400,278 B2
• Filed: 05/30/2007
• Issued: 03/19/2013
• Est. Priority Date: 05/31/2006
• Status: Active Grant

• Current Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Original Assignee: Semiconductor Energy Laboratory Co., Ltd.
• Inventors: Koyama, Jun
• Primary Examiner(s): Lee, Benjamin C
• Assistant Examiner(s): PHAM, QUANG
• Application Number:
  US11/806,133
• Publication Number:
  US 20070285246A1
• Time in Patent Office: 2,120 Days
• Field of Search: 340/572.1, 340/10.34, 361/18, 320/166
• US Class Current: 340/10.51
• CPC Class Codes: G06F 1/263 Arrangements for using multiple switchable power supplies, e.g. battery and AC G06F1/30 takes precedence
• CPC Class Codes: G06K 19/0702 the arrangement including a battery
• 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 19/07749 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: H01L 21/84 the substrate being other than a semiconductor body, e.g. being an insulating body
• CPC Class Codes: H01L 27/12 the substrate being other than a semiconductor body, e.g. an insulating body
• CPC Class Codes: H02J 50/10 using inductive coupling
• CPC Class Codes: H02J 50/80 involving the exchange of data, concerning supply or distribution of electric power, between transmitting devices and receiving devices
• CPC Class Codes: H04B 5/79 for data transfer in combination with power transfer

Abstract

The present invention provides a power supply circuit provided with a battery as a power source for supplying power to an RFID, and the battery of the power supply circuit is charged with a wireless signal. Then, a switching circuit is provided in the power supply circuit that supplies power to a signal control circuit which transmits and receives individual information to and from the outside to intermittently control supply of power to the signal control circuit by a signal from a low-frequency signal generation circuit.

Claims

1. A semiconductor device comprising:

an antenna circuit;

a power supply circuit; and

a signal control circuit, wherein the power supply circuit comprises;

a rectifier circuit which rectifies signals from the antenna circuit;

a control circuit;

a battery which is charged by the rectified signals;

a low-frequency signal generation circuit which receives the rectified signals;

a switching circuit; and

a power source circuit,

wherein the control circuit is configured to supply a power outputted from the rectifier circuit to the power source circuit through the switching circuit and to charge the battery when a voltage outputted from the rectifier circuit is higher enough than a voltage of the battery,

wherein the control circuit is configured to supply the power outputted from the rectifier circuit to the power source circuit through the switching circuit and not to charge the battery when the voltage outputted from the rectifier circuit is not higher enough but still higher than the voltage of the battery, and to supply a power of the battery to the power source circuit through the switching circuit and not to charge the battery when the voltage outputted from the rectifier circuit is lower than the voltage of the battery,

wherein the low-frequency signal generation circuit comprises;

a ring oscillator that outputs an oscillation signal at a frequency;

a divider circuit configured to divide the frequency of the oscillation signal outputted from the ring oscillator and provide an output of plurality of sequentially divided oscillation signals; and

an AND circuit configured to generate a low-duty ratio signal from the output of the divider circuit, and

wherein the switching circuit controls the power supplied from the battery to the power source circuit and the power outputted from the rectifier circuit to the power source circuit, by the low-duty ratio signal from the low-frequency signal generation circuit.

3. A semiconductor device according to claim 1 or 2, wherein the battery is one selected from the group consisting of a lithium battery, a nickel-metal-hydride battery, a nickel-cadmium battery, an organic-radical battery and a capacitor.

4. A semiconductor device according to claim 1 or 2, wherein the battery includes an anode active material layer, a solid electrolyte layer over the anode active material layer, a cathode active material layer over the solid electrolyte layer, and a collector thin film over the cathode active material layer.

6. A semiconductor device according to claim 1 or 2, further comprising a booster antenna, and the antenna circuit receives a signal from the outside through the booster antenna.

7. A semiconductor device according to claim 1 or 2, wherein the antenna circuit includes a first antenna circuit for receiving power to charge the battery and a second antenna circuit for transmitting and receiving signals to and from the signal control circuit.

8. A semiconductor device according to claim 7, wherein the first antenna circuit includes a plurality of antenna circuits.

9. A semiconductor device according to claim 7, wherein one of the first antenna circuit and the second antenna circuit receives a signal by using electromagnetic induction.

10. A semiconductor device according to claim 1 or 2, wherein the low-frequency signal generation circuit generates the low-duty ratio signal outputted to the switching circuit by frequency-division of clock signals.

11. A semiconductor device according to claim 1 or 2, wherein the signal control circuit includes an amplifier circuit, a modulation circuit, a demodulation circuit, a logic circuit, and a memory control circuit.

12. An IC label comprising the semiconductor device according to claim 1 or 2.

13. An IC tag comprising the semiconductor device according to claim 1 or 2.

14. An IC card comprising the semiconductor device according to claim 1 or 2.

2. A semiconductor device comprising:

an antenna circuit;

a power supply circuit; and

a signal control circuit,

wherein the power supply circuit comprises;

a rectifier circuit which rectifies signals from the antenna circuit;

a control circuit;

a battery which is charged by the rectified signals;

a low-frequency signal generation circuit which receives the rectified signals;

a switching circuit; and

a power source circuit,

wherein the control circuit compares a voltage outputted from the rectifier circuit with a voltage of the battery to select power supplied to the switching circuit from power from the rectifier circuit and power from the battery,

wherein the control circuit is configured to supply the power outputted from the rectifier circuit to the power source circuit through the switching circuit and to charge the battery when the voltage outputted from the rectifier circuit is higher enough than the voltage of the battery, to supply power outputted from the rectifier circuit to the power source circuit through the switching circuit and not to charge the battery when the voltage outputted from the rectifier is not higher enough but still higher than the voltage of the battery, and to supply a power of the battery to the power source circuit through the switching circuit and not to charge the battery when the voltage outputted from the rectifier circuit is lower than the voltage of the battery,

wherein the low-frequency signal generation circuit comprises;

a ring oscillator that outputs an oscillation signal at a frequency;

a divider circuit configured to divide the frequency of the oscillation signal outputted from the ring oscillator and provide an output of plurality of sequentially divided oscillation signals; and

an AND circuit configured to generate a low-duty ratio signal from the output of the divider circuit, and

wherein the switching circuit controls the power supplied from the battery to the power source circuit through the control circuit and the power outputted from the rectifier circuit to the power source circuit, by the low-duty ratio signal from the low frequency signal generation circuit.

5. A semiconductor device according to claim 2, wherein the control circuit is a circuit which connects the battery and the switching circuit when power from the rectifier circuit is less than power from the battery, and does not connect the battery and the switching circuit when power from the battery is less than power from the rectifier circuit.