INTEGRATED CIRCUIT CARD SYSTEM AND A DATA TRANSMISSION METHOD THEREOF

• US 20100245048A1
• Filed: 03/05/2010
• Published: 09/30/2010
• Est. Priority Date: 03/31/2009
• Status: Active Grant

• Current Assignee: Samsung Electronics Co. Ltd.
• Original Assignee: Samsung Electronics Co. Ltd.
• Inventors: Kim, Ki Hong
• Granted Patent: US 8,854,211 B2
• Time in Patent Office: Days
• US Class Current: 340/10.100
• CPC Class Codes: G08C 19/02 in which the signal transmitted is magnitude of current or voltage G08C19/36, G08C19/38 take precedence

Abstract

An integrated circuit card system that includes a radio frequency (RF) integrated circuit configured to wirelessly communicate with an integrated circuit card reader; and an integrated circuit card, which is connected to the RF integrated circuit by a single wire, the integrated circuit card configured to change an amount of current of a data signal output from the integrated circuit card according to a transmission speed of a data signal input to the integrated circuit card from the RF integrated circuit.

Claims

1. A transmission method, comprising:

receiving a first data signal transmitted in accordance with a single wire protocol;

determining a transmission speed of the first data signal; and

outputting a second data signal in accordance with the single wire protocol, wherein an amount of current of the second data signal is changed according to the transmission speed of the first data signal.

2. The transmission method of claim 1, wherein determining the transmission speed of the first data signal comprises:

detecting a first edge of the first data signal to generate a first edge detection signal;

beginning a clock cycle count in response to the first edge detection signal;

detecting a second edge of the first data signal to generate a second edge detection signal, the second edge corresponding to the same transition as the first edge; and

ending the clock cycle count in response to the second edge detection signal to output the count.

3. The transmission method of claim 2, wherein changing the amount of current of the second data signal comprises:

receiving the count; and

increasing the amount of current of the second data signal in response to the count being less than a predetermined value or decreasing the amount of current of the second data signal in response to the count being not less than the predetermined value.

4. An integrated circuit card system, comprising:

a radio frequency (RF) integrated circuit configured to wirelessly communicate with an integrated circuit card reader; and

an integrated circuit card connected to the RF integrated circuit by a single wire, the integrated circuit card configured to change an amount of current of a data signal output from the integrated circuit card according to a transmission speed of a data signal input to the integrated circuit card from the RF integrated circuit.

5. The integrated circuit card system of claim 4, wherein the integrated circuit card comprises:

a transmission speed calculator configured to determine the transmission speed of the input data signal;

a current driver configured to provide the current corresponding to the output data signal;

a transistor connected between the current driver and a ground voltage, the transistor configured to be controlled by the output data signal,

wherein the transmission speed calculator is configured to control the current provided by the current driver according to the transmission speed of the input data signal.

6. The integrated circuit card system of claim 5, wherein the transmission speed calculator comprises:

a clock generator configured to generate a clock;

an edge detector configured to detect first and second edges of the input data signal, the second edge corresponding to the same transition as the first edge;

a counter configured to begin counting a cycle of the clock in response to the detection of the first edge, and end the clock cycle counting in response to the detection of the second edge and output the count; and

a calculator configured to generate a signal to control the current provided by the current driver according to the count.

7. The integrated circuit card system of claim 6, wherein the integrated circuit card further comprises a plurality of pads, wherein at least one of the pads is connected to the RF integrated circuit by the single wire.

8. The integrated circuit card system of claim 7, wherein the plurality of pads comprises eight pads.

9. The integrated circuit card system of claim 6, wherein the current driver comprises a plurality of switches, each switch serially connected between an input terminal of the integrated circuit card and a respective current source, the current sources connected to an output terminal of the integrated circuit card, and the switches configured to be activated in response to the signal generated by the calculator.

10. The integrated circuit card system of claim 6, wherein the first and second edges of the input data signal comprise rising edges of the input data signal or falling edges of the input data signal.

11. The integrated circuit card system of claim 4, wherein the input signal and the output signal are transmitted between the RF integrated circuit and the integrated circuit card according to a single wire protocol.

12. The integrated circuit card system of claim 4, wherein the RF integrated circuit comprises an antenna for wirelessly communicating with the integrated circuit card reader.

13. The integrated circuit card system of claim 4, wherein the input data signal comprises data ‘

1’

in response to a high voltage level of the input data signal being longer than a low voltage level of the input data signal during a period of the input data signal.

14. The integrated circuit card system of claim 4, wherein the input data signal comprises data ‘

0’

in response to a high voltage level of the input data signal being shorter than a low voltage level of the input data signal during a period of the input data signal.

15. The integrated circuit card system of claim 4, wherein the output data signal comprises data ‘

1’

in response to the amount of current being equal to or greater than a predetermined value.

16. The integrated circuit card system of claim 4, wherein the output data signal comprises data ‘

0’

in response to the amount of current being less than a predetermined value.

17. The integrated circuit card system of claim 4, wherein the integrated circuit card is included in a subscriber identification module (SIM) card.

18. The integrated circuit card system of claim 4, wherein the RF integrated circuit is included in a SIM card.

19. The integrated circuit card system of claim 4, wherein the RF integrated circuit and the integrated circuit card are part of a mobile system.

20. A radio frequency identification (RFID) system, comprising:

an RFID reader configured to read data from an RFID tag,

wherein the RFID reader comprises;

an RF integrated circuit configured to wirelessly communicate with the RFID tag; and

an integrated circuit card connected to the RF integrated circuit by a single wire, the integrated circuit card configured to change an amount of current of a data signal output from the integrated circuit card according to a transmission speed of a data signal input to the integrated circuit card from the RF integrated circuit.