Battery-Centric Tamper Resistant Circuitry and Portable Electronic Devices

• US 20090085737A1
• Filed: 09/28/2007
• Published: 04/02/2009
• Est. Priority Date: 09/28/2007
• Status: Active Grant

• Current Assignee: Texas Instruments, Inc.
• Original Assignee: Texas Instruments, Inc.
• Inventors: Hollander, James F., Estevez, Leonardo W.
• Granted Patent: US 8,249,666 B2
• Time in Patent Office: Days
• US Class Current: 340/531
• CPC Class Codes: G06F 21/81 by operating on the power supply, e.g. enabling or disabling power-on, sleep or resume operations
• CPC Class Codes: H04M 1/724 User interfaces specially adapted for cordless or mobile telephones

Abstract

Tamper-resistant circuitry for use with an electronic device is provided, where the electronic device comprises a plurality of connections for coupling the tamper-resistant circuitry to functional circuitry for performing functionality in connection with the electronic device. The tamper-resistant circuitry comprises an interface for coupling to the plurality of connections and a power source for coupling to at least one connection in the plurality of connections. The tamper-resistant circuitry further comprises circuitry operable to evaluate a measure of an operational parameter related to the power source and in response to a signal at at least one connection in the plurality of connections, to provide an acceptable range for the operational parameter, and to inhibit standard operation of the functional circuitry in response to detecting an anomaly in the functional circuitry by detecting that the measure is outside the acceptable range.

Claims

1. Tamper-resistant circuitry for use with an electronic device, the electronic device comprising a plurality of connections for coupling the tamper-resistant circuitry to functional circuitry for performing functionality in connection with the electronic device, the tamper-resistant circuitry comprising:

an interface for coupling to the plurality of connections;

a power source for coupling to at least one connection in the plurality of connections; and

circuitry operable to evaluate a measure of an operational parameter related to the power source and in response to a signal at at least one connection in the plurality of connections, to provide an acceptable range for the operational parameter, and to inhibit standard operation of the functional circuitry in response to detecting an anomaly in the functional circuitry by detecting that the measure is outside the acceptable range.

2. The tamper-resistant circuitry of claim 1 wherein the anomaly is representative of a change in electrical attributes of the functional circuitry as compared to electrical attributes of the functional circuitry at a time when the electronic device was manufactured.

3. The tamper-resistant circuitry of claim 1 wherein the anomaly comprises a change in impedance between two connections in the plurality of connections.

4. The tamper-resistant circuitry of claim 1 wherein the circuitry for inhibiting is for terminating provision of power from the power source to the at least one connection in response to detecting an anomaly in the functional circuitry by detecting that the measure is outside the acceptable range.

5. The tamper-resistant circuitry of claim 1 wherein the interface, the power source, the circuitry to evaluate, provide and inhibit are part of a battery unit for coupling to the electronic device.

7. The tamper-resistant circuitry of claim 1 wherein the circuitry to evaluate, provide and inhibit includes a memory for storing the evaluated measure and the acceptable range.

8. The tamper-resistant circuitry of claim 1 wherein the circuitry to evaluate, provide and inhibit is operable to determine a value representative of at least one of impedance, current, and voltage at at least one connection in the plurality of connections;

and includes a memory for storing the determined value as an acceptable value within the acceptable range.

9. The tamper-resistant circuitry of claim 8 wherein the acceptable range is determined in response to the determined value as adjusted by a delta value.

10. The tamper-resistant circuitry of claim 1 wherein the acceptable range is determined in response to a plurality of enabled use cases in the electronic device.

11. The tamper-resistant circuitry of claim 10 wherein the circuitry to evaluate, provide and inhibit is operable to request and receive from the electronic device an indication of each of the plurality of enabled use cases.

12. The tamper-resistant circuitry of claim 1 wherein the circuitry to evaluate, provide and inhibit is operable to request and store a unique identifier from the electronic device.

13. The tamper-resistant circuitry of claim 12 wherein the unique identifier is stored at a first time period, and wherein the circuitry to evaluate, provide and inhibit is operable to inhibit standard operation of the functional circuitry in response to receiving, at a second time period following the first time period, an identifier from the electronic device that differs from the unique identifier.

14. The tamper-resistant circuitry of claim 1 further comprising circuitry for communicating software to the electronic device.

15. The tamper-resistant circuitry of claim 1 further comprising circuitry for requesting the electronic device to enable the functional circuitry and wherein the circuitry to evaluate, provide and inhibit is operable to determine a measure for the acceptable range while the functional circuitry is enabled.

16. The tamper-resistant circuitry of claim 15 wherein the circuitry to evaluate, provide and inhibit is operable to enable the functional circuitry at a power level during the determination of the measure that lower than a power level of the functional circuitry during normal operations of the electronic device.

17. The tamper-resistant circuitry of claim 1 wherein the circuitry to evaluate, provide and inhibit is operable to cause the electronic device to communicate a message in response to the detecting of the anomaly.

18. The tamper-resistant circuitry of claim 17 wherein the message is perceivable by a user of the electronic device.

19. The tamper-resistant circuitry of claim 17 wherein the message comprises a wireless message to a device operable to communicate with the electronic device.

20. The tamper-resistant circuitry of claim 1 and further comprising circuitry for causing random operation of the electronic device in response to detecting the anomaly.

21. The tamper-resistant circuitry of claim 1:

wherein the functional circuitry comprises circuitry for coupling to an interface of the electronic device after manufacture of the electronic device; and

wherein the circuitry operable to inhibit is operable to inhibit standard operation of the circuitry for coupling to an interface in response to detecting an anomaly in the circuitry for coupling to an interface by detecting that the measure is outside the acceptable range.

6. The tamper-resistant circuitry of claim 6 wherein the battery unit comprises an encapsulated battery unit.

22. Tamper-resistant circuitry for use with an electronic device, the electronic device comprising a plurality of connections for coupling the tamper-resistant circuitry to functional circuitry for performing functionality in connection with the electronic device, the tamper-resistant circuitry comprising:

an interface for coupling to the plurality of connections;

a power source for coupling to at least one connection in the plurality of connections; and

circuitry operable to evaluate a measure of an operational parameter related to the power source and in response to a signal at at least one connection in the plurality of connections, to provide an acceptable range for the operational parameter, and to inhibit standard operation of the functional circuitry in response to detecting an anomaly in the functional circuitry by detecting that the measure is outside the acceptable range and in response by terminating provision of power from the power source to the at least one connection;

wherein the anomaly is representative of a change in electrical attributes of the functional circuitry as compared to electrical attributes of the functional circuitry at a time when the electronic device was manufactured; and

wherein the interface, the power source, and the circuitry to evaluate, provide and inhibit are part of a battery unit for coupling to the electronic device.

23. A combination of devices, comprising:

an electronic device, comprising;

functional circuitry for performing functionality in connection with the electronic device; and

a plurality of connections; and

tamper-resistant circuitry for use with the electronic device, comprising;

an interface for coupling to the plurality of connections;

a power source for coupling to at least one connection in the plurality of connections and operable to provide power to the functional circuitry; and

circuitry operable to evaluate a measure of an operational parameter related to the power source and in response to a signal at at least one connection in the plurality of connections, to provide an acceptable range for the operational parameter, and to inhibit standard operation of the functional circuitry in response to detecting an anomaly in the functional circuitry by detecting that the measure is outside the acceptable range.

24. The devices of claim 23 wherein the anomaly is representative of a change in electrical attributes of the functional circuitry as compared to electrical attributes of the functional circuitry at a time when the electronic device was manufactured.

25. A method of improving tamper-resistance of an electronic device, the electronic device comprising a plurality of connections for coupling the tamper-resistant circuitry to functional circuitry for performing functionality in connection with the electronic device, the tamper-resistant circuitry comprising:

coupling a power source to at least one connection in a plurality of connections of the electronic device;

evaluating a measure of an operational parameter related to the power source and in response to a signal at at least one connection in the plurality of connections; and

inhibiting standard operation of the functional circuitry in response to detecting an anomaly in the functional circuitry by detecting that the measure is outside an acceptable range for the operational parameter.