Dual mode smart card and associated methods

• US 6,439,464 B1
• Filed: 10/11/2000
• Issued: 08/27/2002
• Est. Priority Date: 10/11/2000
• Status: Expired due to Term

• Current Assignee: Schlumberger Holdings Corporation (Schlumberger NV), STMicroelectronics Incorporated (STMicroelectronics NV)
• Original Assignee: Schlumberger Holdings Corporation (Schlumberger NV), STMicroelectronics Incorporated (STMicroelectronics NV)
• Inventors: Fruhauf, Serge F., Goupil, Herve, Leydier, Robert
• Primary Examiner(s): Frech, Karl D.
• Assistant Examiner(s): Nowlin, April
• Application Number:
  US09/686,925
• Time in Patent Office: 685 Days
• Field of Search: 235/492
• US Class Current: 235/492
• CPC Class Codes: G06K 19/07 with integrated circuit chips
• CPC Class Codes: G06K 19/07733 the record carrier containing at least one further contact interface not conform ISO-7816

Abstract

A dual-mode IC is provided for operating in first mode such as an ISO mode in accordance with International Standards Organization 7816 (ISO 7816) protocol, and a second, non-ISO mode, such as a USB mode in accordance with Universal Serial Bus (USB) protocol. The dual-mode IC is preferably in a smart card and includes a microprocessor, a switching block, and an external interface. The external interface includes a voltage supply pad, a reference voltage pad, a reset pad, a clock pad and an input/output pad in accordance with the ISO 7816 protocol, and a D-plus pad and D-minus pad in accordance with the USB protocol. The IC further includes a mode configuration circuit for detecting a USB mode condition on at least one of the D-plus and D-minus pads, and configuring the IC in the ISO mode or the USB mode depending on the result. Once the IC is configured in a particular mode, it will operate in only that mode until the next power-on reset sequence.

Claims

1. A dual-mode integrated circuit (IC) for operating in an ISO mode in accordance with International Standards Organization 7816 (ISO 7816) protocol, and a USB mode in accordance with a Universal Serial Bus protocol, the dual-mode IC comprising:

a microprocessor;

a switching block connected to the microprocessor;

an external interface connected to the switching block and comprising

a voltage supply pad,

a reference voltage pad,

a reset pad, a clock pad and an input/output pad in accordance with the ISO 7816 protocol, and

a D-plus pad and a D-minus pad in accordance with the USB protocol; and

a mode configuration circuit connected to the switching block for configuring the dual-mode IC in one of the ISO and USB modes based upon a signal on at least one of the D-plus and D-minus pads.

2. The dual-mode IC according to claim 1 wherein the mode configuration circuit comprises:

a USB mode detector connected to at least the D-minus pad for detecting a USB condition; and

a latching circuit connected to the switching block and receiving an output from the USB mode detector.

3. The dual-mode IC according to claim 2 wherein the mode configuration circuit configures the dual-mode IC in the USB mode if a USB condition is detected by the USB mode detector, and configures the dual-mode IC in the ISO mode if a USB condition is not detected by the USB mode detector.

4. The dual-mode IC according to claim 2 wherein the USB mode detector is also connected to the D-plus pad.

5. The dual-mode IC according to claim 2 wherein the mode configuration circuit further comprises an ISO mode detector connected between the reset pad and the latching circuit for detecting an ISO condition.

6. The dual-mode IC according to claim 5 wherein the mode configuration circuit configures the dual-mode IC in the USB mode if a USB condition is detected by the USB mode detector, and configures the dual-mode IC in the ISO mode if an ISO condition is detected by the ISO mode detector.

7. The dual-mode IC according to claim 2 further comprising a control register connected to the latching circuit for storing a mode configuration indicator.

8. The dual-mode IC according to claim 2 further comprising a USB voltage detector connected between the voltage supply pad and the latching circuit to detect a USB voltage supply.

9. The dual-mode IC according to claim 1 wherein the mode configuration circuit configures the dual-mode IC to operate in one of the ISO and USB modes while disabling the other of the ISO and USB modes.

10. The dual-mode IC according to claim 9 wherein the reset, clock and input/output pads are disabled when the dual-mode IC is configured in the non-ISO mode, and the D-plus and D-minus pads are disabled when the dual-mode IC is configured in the ISO mode.

11. A dual-mode smart card for operating in an ISO mode in accordance with International Standards Organization 7816 (ISO 7816) protocol, and a USB mode in accordance with a Universal Serial Bus protocol, the dual-mode smart card comprising:

a card body; and

a dual-mode integrated circuit (IC) carried by the card body and comprising

an external interface including

a voltage supply pad,

a reference voltage pad,

a first set of pads including a reset pad, a clock pad and an input/output pad in accordance with the ISO 7816 protocol, and

a second set of pads including a D-plus pad and a D-minus pad in accordance with the USB protocol, and

a mode configuration circuit for configuring the dual-mode IC in one of the ISO and USB modes and comprising

a USB mode detector connected to at least the D-minus pad for detecting a USB condition, and

a latching circuit connected to the USB mode detector.

12. The dual-mode smart card according to claim 11 wherein the mode configuration circuit configures the dual-mode IC in the USB mode if a USB condition is detected by the USB mode detector, and configures the dual-mode IC in the ISO mode if a USB condition is not detected by the USB mode detector.

13. The dual-mode smart card according to claim 11 wherein the USB mode detector is also connected to the D-plus pad.

14. The dual-mode smart card according to claim 11 wherein the dual mode IC further comprises an ISO mode detector connected between the reset pad and the latching circuit for detecting an ISO condition.

15. The dual-mode smart card according to claim 14 wherein the mode configuration circuit configures the dual-mode IC in the USB mode if a USB condition is detected by the USB mode detector, and configures the dual-mode IC in the ISO mode if an ISO condition is detected by the ISO mode detector.

16. The dual-mode smart card according to claim 11 wherein the dual-mode IC further comprises a control register connected to the latching circuit for storing a mode configuration indicator.

17. The dual-mode smart card according to claim 11 wherein the mode configuration circuit further comprises a USB voltage detector connected between the voltage supply pad and the latching circuit to detect a USB voltage supply.

18. The dual-mode smart card according to claim 11 wherein the mode configuration circuit configures the dual-mode IC to operate in one of the ISO and non-ISO modes while disabling the other of the ISO and non-ISO modes.

19. The dual-mode smart card according to claim 18 wherein the reset, clock and input/output pads are disabled when the dual-mode IC is configured in the USB mode, and the D-plus and D-minus pads are disabled when the dual-mode IC is configured in the ISO mode.

20. A dual-mode smart card system for operating in an ISO mode in accordance with International Standards Organization 7816 (ISO 7816) protocol, and a USB mode in accordance with a Universal Serial Bus protocol, the dual-mode smart card system comprising:

a dual-mode smart card including

a dual-mode integrated circuit (IC) comprising

an external interface including

a voltage supply pad,

a reference voltage pad,

a reset pad, a clock pad and an input/output pad in accordance with the ISO 7816 protocol, and

a D-plus pad and a D-minus pad in accordance with the USB protocol, and

a mode configuration circuit for configuring the dual-mode IC in one of the ISO mode and the USB mode and comprising

a USB mode detector connected to the D- minus pad, and

a latching circuit connected to the USB mode detector;

at least one of an ISO-compliant smart card reader and a USB-compliant smart card reader for reading the dual-mode smart card, the ISO-compliant smart card reader including an ISO interface having a plurality of contacts for respectively mating with the voltage supply pad, the reference voltage pad, the reset pad, the clock pad and the input/output pad in accordance with the ISO 7816 protocol, and the USB-compliant smart card reader including a USB interface having a plurality of contacts for respectively mating with the voltage supply pad, the reference voltage pad, the D-plus pad and the D-minus pad in accordance with the USB protocol.

21. The dual-mode smart card system according to claim 20 wherein the mode configuration circuit configures the dual-mode IC in the USB mode if a USB condition is detected by the USB mode detector, and configures the dual-mode IC in the ISO mode if a USB condition is not detected by the USB mode detector.

22. The dual-mode smart card system according to claim 20 wherein the USB mode detector is also connected to the D-plus pad.

23. The dual-mode smart card system according to claim 20 wherein the mode configuration circuit further comprises an ISO mode detector connected between the reset pad and the latching circuit for detecting an ISO condition.

24. The dual-mode smart card system according to claim 23 wherein the mode configuration circuit configures the dual-mode IC in the USB mode if a USB condition is detected by the USB mode detector, and configures the dual-mode IC in the ISO mode if an ISO condition is detected by the ISO mode detector.

25. The dual-mode smart card system according to claim 20 wherein the mode configuration circuit further comprises a control register connected to the latching circuit for storing a mode configuration indicator.

26. The dual-mode smart card system according to claim 20 wherein the mode configuration circuit further comprises a USB voltage detector connected between the voltage supply pad and the latching circuit to detect a USB voltage supply.

27. The dual-mode smart card system according to claim 20 wherein the mode configuration circuit configures the dual-mode IC to operate in one of the ISO and USB modes while disabling the other of the ISO and USB modes.

28. The dual-mode smart card system according to claim 27 wherein the reset, clock and input/output pads are disabled when the dual-mode IC is configured in the USB mode, and the D-plus and D-minus pads are disabled when the dual-mode IC is configured in the ISO mode.

29. A method of operating a dual-mode integrated circuit (IC) in an ISO mode in accordance with International Standards Organization 7816 (ISO 7816) protocol, and a USB mode in accordance with a Universal Serial Bus protocol, the dual-mode IC including an external interface having a voltage supply pad, a first set of pads including a reset pad, a clock pad and an input/output pad in accordance with the ISO protocol, and a second set of pads including a D-plus pad and a D-minus pad in accordance with the USB protocol, the method comprising:

detecting whether a USB-mode condition exists on at least one pad of the second set of pads;

configuring the dual-mode IC in one of the ISO mode and the USB mode based upon the detection; and

disabling one of the first and second set of pads based upon the configuration.

30. The method according to claim 29 wherein detecting whether the USB-mode condition exists on at least one pad of the second set of pads comprises detecting whether the USB-mode condition exists during a power-on-reset of the dual-mode IC.

31. The method according to claim 29 wherein detecting whether the USB-mode condition exists on at least one pad of the second set of pads comprises detecting whether the USB-mode condition exists on the D-minus pad.

32. The method according to claim 29 wherein detecting whether the USB-mode condition exists on at least one pad of the second set of pads comprises detecting whether the USB-mode condition exists on the D-plus pad and the D-minus pad.

33. The method according to claim 29 wherein the dual-mode IC is configured in the USB mode when the USB-mode condition is detected, and configured in the ISO mode when the USB-mode condition is not detected.

34. The method according to claim 29 further comprising detecting whether an ISO-mode condition exists on one pad of the first set of pads during a power-on-reset of the dual-mode IC;

wherein the dual-mode IC is configured in the USB mode upon the detection of the USB-mode condition, and configured in the ISO mode upon detection of the ISO-mode condition.

35. The method according to claim 34 wherein detecting whether the ISO-mode condition exists on one pad of the first set of pads comprises detecting whether the ISO-mode condition exists on the reset pad.

36. The method according to claim 29 further comprising verifying the USB mode, when the USB-mode condition is detected, by detecting a USB-mode voltage on the voltage supply pad.

37. The method according to claim 29 further comprising storing a mode configuration indicator for indicating whether the dual-mode IC is configured in the ISO or USB mode.