Semiconductor integrated circuit device, and non-contact type IC card and portable information terminal using the semiconductor integrated circuit device

• US 7,505,794 B2
• Filed: 01/30/2004
• Issued: 03/17/2009
• Est. Priority Date: 01/30/2004
• Status: Active Grant

• Current Assignee: Renesas Electronics Corporation
• Original Assignee: Renesas Technology Corporation (Renesas Electronics Corporation)
• Inventors: Kubota, Masaru, Watanabe, Kazuki, Matsushita, Kazuhiro
• Primary Examiner(s): Tran, Pablo N
• Application Number:
  US10/583,716
• Publication Number:
  US 20070155442A1
• Time in Patent Office: 1,873 Days
• Field of Search: 455/572, 455/343.1, 455/571, 455/573, 455/574, 455/333, 455/343.2, 455/343.5, 455/343.6, 455/550.1, 455/575.1, 455/90.3, 455/127.1, 455/127.5, 455/128, 455/129, 323268-273
• US Class Current: 455/572
• CPC Class Codes: G06K 19/0701 at least one of the integrated circuit chips comprising an arrangement for power management
• CPC Class Codes: G06K 19/0723 the record carrier comprising an arrangement for non-contact communication, e.g. wireless communication circuits on transponder cards, non-contact smart cards or RFIDs

Abstract

The present invention provides a semiconductor integrated circuit device and a non-contact type IC card and a portable information terminal which uses the semiconductor integrated circuit device. The semiconductor integrated circuit device includes antenna terminals LA, LB which are connected to an antenna L1, a power source circuit B5 which has a rectifier/smoothing circuit B1 which obtains a DC voltage by rectifying and smoothing an AC signal which is supplied to the antenna terminal from the antenna and a shunt regulator B6 and a series regulator B7 which stabilize the DC voltage, and an internal circuit B8 which is operated upon the supply of the DC voltage from the power source circuit. The series regulator operates and the shunt regulator stops in a stage that a signal is transmitted to a reader/writer. The shunt regulator operates and the series regulator stops in a stage other than the stage that the signal is transmitted to the reader/writer.

Claims

1. A semiconductor integrated circuit device comprising:

an antenna terminal which is connected to an antenna;

a power source circuit which has a rectifier/smoothing circuit which obtains a DC voltage by rectifying and smoothing an AC signal which is supplied to the antenna terminal from the antenna, and a shunt regulator and a series regulator which stabilize the DC voltage; and

an internal circuit which is operated upon the supply of the DC voltage from the power source circuit,

wherein the series regulator performs a voltage stabilizing operation and the shunt regulator stops a voltage stabilizing operation in a stage that a signal is transmitted to a reader/writer, and

wherein the shunt regulator performs a voltage stabilizing operation and the series regulator stops a voltage stabilizing operation in a stage that inner processing is performed.

2. A semiconductor integrated circuit device according to claim 1,

wherein the semiconductor integrated circuit device further includes a load modulator which is connected to the antenna terminals, and

wherein the signal is transmitted to the reader/writer in response to the presence or non-presence of an electric current which flows in the load modulator.

3. An IC card comprising:

a coil which constitutes an antenna; and

a semiconductor integrated circuit device,

wherein the semiconductor integrated circuit device comprises;

an antenna terminal which is connected to the antenna;

a power source circuit which includes a rectifier/smoothing circuit which outputs a power source voltage by rectifying and smoothing an AC signal which is inputted to the antenna terminal, and a regulator which stabilizes a voltage of the power source voltage and outputs the stabilized power source voltage to a power source terminal; and

an internal circuit which includes a control circuit which generates a control signal which controls a voltage stabilizing operation of the power source circuit,

wherein the power source circuit is controlled in response to the control signal such that a voltage between the rectifier/smoothing circuit and the power source terminal is changed in a stage that a signal is transmitted to a reader/writer and is controlled in response to the control signal such that a current which flows between the power source terminal and a ground terminal is changed in a stage that inner processing is performed.

4. An IC card according to claim 3, wherein the antenna terminal is constituted of two terminals for inputting the AC signal from the antenna, and the internal circuit includes a load modulator which is connected between one terminal out of two terminals and the ground terminal, and the signal is transmitted to the reader/writer in response to the presence or non-presence of an electric current which flows in the load modulator.

5. An IC card according to claim 3, wherein the regulator is operated as a series regulator in the stage that the signal is transmitted to the reader/writer, and is operated as a shunt regulator in the stage that the inner processing is performed.

6. An IC card according to claim 3,

wherein the regulator is constituted of a shunt regulator and a series regulator, and

wherein the series regulator performs a voltage stabilizing operation in response to the control signal in the stage that the signal is transmitted to the reader/writer, and the shunt regulator performs a voltage stabilizing operation in response to the control signal in the stage that the inner processing is performed.

7. A portable information terminal comprising:

a data processing circuit which processes data;

a display device which displays data which is inputted to and outputted from the data processing circuit;

an input device which inputs data to the data processing device; and

an IC card which includes a coil which constitutes an antenna and a semiconductor integrated circuit device, and is electrically connected with the display device,

wherein the semiconductor integrated circuit device comprises;

an antenna terminal which is connected to the antenna;

a power source circuit which includes a rectifier/smoothing circuit which outputs a power source voltage by rectifying and smoothing an AC signal which is inputted to the antenna terminal, and a regulator which stabilizes a voltage of the power source voltage and outputs the stabilized power source voltage to a power source terminal; and

an internal circuit which includes a control circuit which controls a voltage stabilizing operation of the power source circuit,

wherein the power source circuit is controlled by the control circuit such that a voltage between the rectifier/smoothing circuit and the power source terminal is changed in a stage that a signal is transmitted to a reader/writer and is controlled by the control circuit such that a current which flows between the power source terminal and a ground terminal is changed in a stage that inner processing is performed, and

wherein data which the IC card possesses is displayed on the display device.

8. A portable information terminal according to claim 7, wherein the antenna terminal is constituted of two terminals for inputting the AC signal from the antenna, and the internal circuit includes a load modulator which is connected between one terminal out of two terminals and the ground terminal, and the signal is transmitted to the reader/writer in response to the presence or non-presence of an electric current which flows in the load modulator.

9. A portable information terminal according to claim 8, wherein the portable information terminal is a mobile phone which further includes a transmission and reception circuit for performing communication using voice or data.

10. A portable information terminal according to claim 7, wherein the regulator is operated as a series regulator in the stage that the signal is transmitted to the reader/writer, and is operated as a shunt regulator in the stage that the inner processing is performed.

11. A portable information terminal according to claim 10, wherein the portable information terminal is a mobile phone which further includes a transmission and reception circuit for performing communication using voice or data.

12. A portable information terminal according to claim 7,

wherein the regulator is constituted of a shunt regulator and a series regulator, and

wherein the series regulator performs a voltage stabilizing operation in the stage that the signal is transmitted to the reader/writer, and the shunt regulator performs a voltage stabilizing operation in the stage that the inner processing is performed.

13. A portable information terminal according to claim 12, wherein the portable information terminal is a mobile phone which further includes a transmission and reception circuit for performing communication using voice or data.

14. A portable information terminal according to claim 7, wherein the portable information terminal is a mobile phone which further includes a transmission and reception circuit for performing communication using voice or data.