Method for determining information about the internal workings of a chip based on electro-magnetic emissions therefrom

• US 7,554,352 B2
• Filed: 11/03/2006
• Issued: 06/30/2009
• Est. Priority Date: 11/04/2005
• Status: Expired due to Fees

• Current Assignee: VNS Portfolio LLC
• Original Assignee: VNS Portfolio LLC
• Inventors: Huie, John
• Primary Examiner(s): Nguyen; Vinh P
• Application Number:
  US11/592,717
• Publication Number:
  US 20070120571A1
• Time in Patent Office: 970 Days
• Field of Search: None
• US Class Current: 324/762.02
• CPC Class Codes: G01R 31/002 where the device under test is an electronic circuit
• CPC Class Codes: G01R 31/31727 Clock circuits aspects, e.g. test clock circuit details, timing aspects for signal generation, circuits for testing clocks G01R31/31725 takes precedence; concerning scan test G01R31/318552, for tester hardware G01R31/31922

Abstract

A novel a method for determining the internal operation of an integrated circuit (IC) includes measuring electromagnetic (EM) emissions from the integrated circuit chip and analyzing the EM emissions. In a particular method, the EM emissions from the IC are measured using an RF close end probe. In a particular method, the electromagnetic emissions are measured with the IC configured in various ways. In the normal operating mode, the emissions are measured while the IC is provided with power and any external clock signal(s). After measuring the emissions of the IC in normal operating mode, the IC is reconfigured by disabling the external clock signal(s) to the IC and remeasuring the emissions. The external clock signal is disabled by disconnecting the power to the IC, disabling the external clock signal, and then reconnecting power to the IC. In yet a third test mode, the external clock signal is reenabled while power continues to be supplied to the IC. Information about the presence and/or proper functioning of internal clocks of the IC can be determined by analyzing the spectral scan data obtained in one or more of the three test modes.

Claims

1. A method for determining the internal operation of an integrated circuit comprising:

measuring electromagnet emissions from said integrated circuit; and

analyzing said electromagnetic emissions; and

wherein

said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies; and

said step of analyzing said electromagnetic emissions includes identifying frequencies corresponding to amplitudes greater than a predetermined amplitude.

2. A method according to claim 1, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF probe.

3. A method A method according to claim 2, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF close end probe.

4. A method according to claim 1, further comprising configuring said integrated circuit prior to said step of measuring said electromagnetic emissions.

5. A method according to claim 4, wherein said step of configuring said integrated circuit includes placing said integrated circuit in its normal operating mode.

6. A method according to claim 5, wherein said step of placing said integrated circuit chip in its normal operating mode includes providing power and any external clock signal to said integrated circuit.

7. A method according to claim 4, wherein said step of configuring said integrated circuit includes:

providing power to said integrated circuit; and

disabling any external clock signal to said integrated circuit.

8. A method according to claim 7, wherein said step of disabling any external clock signal to said integrated circuit includes:

disconnecting power to said integrated circuit;

disabling any external clock signal to said integrated circuit; and

reconnecting power to said integrated circuit.

9. A method according to claim 4, wherein said step of configuring said integrated circuit includes reenabling a disabled external clock signal to said integrated circuit while power is supplied to said integrated circuit.

10. A method according to claim 4, wherein said step of configuring said integrated circuit includes re-enabling a disabled external clock signal to said integrated circuit while power is supplied to said integrated circuit.

11. A method according to claim 1, further comprising:

configuring said integrated circuit prior to said step of measuring said electromagnetic emissions;

reconfiguring said integrated circuit differently after said step of measuring said electromagnetic emissions; and

remeasuring said electromagnetic emissions from said integrated circuit after said step of reconfiguring said integrated circuit.

12. A method according to claim 1, further comprising:

configuring said integrated circuit by supplying power and any external clock signal to said integrated circuit prior to measuring said electromagnetic emissions;

reconfiguring said integrated circuit alter said step of measuring said electromagnetic emissions by disconnecting power to said integrated circuit, disabling any external clock signal to said integrated circuit, and reconnecting power to said integrated circuit; and

remeasuring said electromagnetic emissions from said integrated circuit after reconfiguring said integrated circuit.

13. A method according to claim 12, further comprising:

reconnecting any external clock signal to said integrated circuit following said step of remeasuring said electromagnetic emissions; and

remeasuring said electromagnetic emissions from said integrated circuit a second time after said step of reconnecting any external clock signal.

14. A method according to claim 1, wherein said step of analyzing said electromagnetic emissions includes determining whether said electromagnetic emissions are below a predetermined RFI level.

15. A method according to claim 1, wherein said step of analyzing said electromagnetic emissions includes comparing said identified frequencies to a predetermined set of frequencies to determine whether one or more clocks of said integrated circuit are operating properly.

16. A method according to claim 1, wherein said step of analyzing said electromagnetic emissions includes comparing said identified frequencies to sets of frequencies associated with known devices to determine whether any of said known devices are embedded in said integrated circuit.

17. A method according to claim 1, further comprising:

disabling any external clock signal to said integrated circuit after said step of measuring said electromagnetic emissions from said integrated circuit; and

remeasuring said electromagnetic emissions from said integrated circuit while said external clock signal is disabled;

identifying frequencies corresponding to amplitudes greater than said predetermined amplitude in said remeasured electromagnetic emissions; and

comparing said identified frequencies of said measured electromagnetic emissions with said identified frequencies of said remeasured electromagnetic emissions.

18. A method according to claim 1, wherein said step of measuring said electromagnetic emissions includes measuring said electromagnetic emissions at several different locations with respect to said integrated circuit.

19. An electronically readable medium having code embodied therein for causing an electronic device to perform the method of claim 1.

20. A method according to claim 1, wherein said step of measuring said electromagnetic emissions includes measuring said electromagnetic emissions at several different locations with respect to said integrated circuit.

21. An apparatus for determining the internal operation of an integrated circuit, comprising:

a probe for sensing electromagnetic radiation from said integrated circuit;

a spectrum capture device operative to convert said electromagnetic radiation sensed by said probe into electronic data; and

a spectrum analyzer operative to process said electronic data to provide information about the internal operation of said integrated circuit; and

wherein said spectrum analyzer is operative to compare said electronic data with sets of electronic data associated with known electronic devices to determine whether one or more of said known electronic devices are embedded in said integrated circuit.

22. An apparatus according to claim 21, further comprising a display for presenting said data from said spectrum analyzer.

23. An apparatus according to claim 22, wherein said spectrum analyzer is operative to present said data on said display in the form of an amplitude versus frequency graph.

24. An apparatus according to claim 21, wherein said spectrum capture device includes a spectrum capture routine and said spectrum analyzer includes a spectrum analyzer routine;

and said apparatus further comprising;

a processing unit for executing code and processing data; and

memory for storing said code, said code including said spectrum capture routine and said spectrum analyzer routine.

25. An apparatus according to claim 24, wherein said spectrum capture device is further operative to control the position of said probe.

26. An apparatus according to claim 21, wherein said spectrum capture device is further operative to selectively interrupt electrical power to said integrated circuit.

27. An apparatus according to claim 21, wherein said spectrum capture device is further operative to selectively enable and disable an external clock signal to said integrated circuit.

28. An apparatus according to claim 21, wherein said spectrum capture device is operative to store said electronic data as records indicative of an electromagnetic spectrum emitted by said integrated circuit.

29. An apparatus according to claim 21, wherein:

said spectrum capture device is operative to capture a first set of spectrum data from said integrated circuit and a second set of spectrum data from said integrated circuit; and

said spectrum analyzer is operative to compare said first set of spectrum data to said second set of spectrum data to identify at least one predetermined difference.

30. An apparatus according to claim 29, wherein said spectrum capture device is operative to selectively disable an external clock signal to said integrated circuit during the capture of one of said first set of spectrum data and said second set of spectrum data.

31. An apparatus according to claim 21, wherein said spectrum analyzer is operative to compare said electronic data to electronic data indicative of an internal clock of said integrated circuit operating properly.

93. An apparatus according to claim 21, wherein said spectrum analyzer is operative to compare said electronic data to electronic data indicative of an internal clock of said integrated circuit operating properly.

32. A method for determining the internal operation of an integrated circuit comprising:

measuring electromagnet emissions from said integrated circuit;

configuring said integrated circuit prior to said step of measuring said electromagnetic emissions;

reconfiguring said integrated circuit differently after said step of measuring said electromagnetic emissions;

remeasuring said electromagnetic emissions from said integrated circuit after said step of reconfiguring said integrated circuit; and

analyzing said electromagnetic emissions.

33. A method according to claim 32, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF probe.

34. A method A method according to claim 33, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF close end probe.

35. A method according to claim 32, wherein said step of configuring said integrated circuit includes placing said integrated circuit in its normal operating mode.

36. A method according to claim 35, wherein said step of placing said integrated circuit chip in its normal operating mode includes providing power and any external clock signal to said integrated circuit.

37. A method according to claim 32, wherein said step of configuring said integrated circuit includes:

providing power to said integrated circuit; and

disabling any external clock signal to said integrated circuit.

38. A method according to claim 37, wherein said step of disabling any external clock signal to said integrated circuit includes:

disconnecting power to said integrated circuit;

disabling any external clock signal to said integrated circuit; and

reconnecting power to said integrated circuit.

39. A method according to claim 32, wherein said step of configuring said integrated circuit includes re-enabling a disabled external clock signal to said integrated circuit while power is supplied to said integrated circuit.

40. A method according to claim 32, wherein:

said step of configuring said integrated circuit includes supplying power and any external clock signal to said integrated circuit prior to measuring said electromagnetic emissions; and

said step of reconfiguring said integrated circuit after said step of measuring said electromagnetic emissions includes disconnecting power to said integrated circuit, disabling any external clock signal to said integrated circuit, and reconnecting power to said integrated circuit.

41. A method according to claim 40, further comprising:

reconnecting any external clock signal to said integrated circuit following said step of remeasuring said electromagnetic emissions; and

remeasuring said electromagnetic emissions from said integrated circuit a second time after said step of reconnecting any external clock signal.

42. A method according to claim 32, wherein said step of analyzing said electromagnetic emissions includes determining whether said electromagnetic emissions are below a predetermined RFI level.

43. A method according to claim 32, wherein:

said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies; and

said step of analyzing said electromagnetic emissions includes

identifying frequencies corresponding to amplitudes greater than a predetermined amplitude, and

comparing said identified frequencies to a predetermined set of frequencies to determine whether one or more clocks of said integrated circuit are operating properly.

44. A method according to claim 32, wherein:

said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies; and

said step of analyzing said electromagnetic emissions includes

identifying frequencies corresponding to amplitudes greater than a predetermined amplitude, and

comparing said identified frequencies to sets of frequencies associated with known devices to determine whether any of said known devices are embedded in said integrated circuit.

45. A method according to claim 32, wherein said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies, and said step of analyzing said electromagnetic emissions includes identifying frequencies corresponding to amplitudes greater than a predetermined amplitude, said method further comprising:

disabling any external clock signal to said integrated circuit after said step of measuring said electromagnetic emissions from said integrated circuit;

remeasuring said electromagnetic emissions from said integrated circuit while said external clock signal is disabled;

identifying frequencies corresponding to amplitudes greater than said predetermined amplitude in said remeasured electromagnetic emissions; and

comparing said identified frequencies of said measured electromagnetic emissions with said identified frequencies of said remeasured electromagnetic emissions.

46. An electronically readable medium having code embodied therein for causing an electronic device to perform the method of claim 32.

47. A method for determining the internal operation of an integrated circuit comprising:

measuring electromagnet emissions from said integrated circuit;

configuring said integrated circuit prior to said step of measuring said electromagnetic emissions; and

analyzing said electromagnetic emissions; and

wherein said step of configuring said integrated circuit includes

providing power to said integrated circuit, and

disabling any external clock signal to said integrated circuit.

48. A meted according to claim 47, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF probe.

49. A method A method according to claim 48, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF close end probe.

50. A method according to claim 47, wherein said step of configuring said integrated circuit includes placing said integrated circuit in its normal operating mode.

51. A method according to claim 47, wherein said step of disabling any external clock signal to said integrated circuit includes:

disconnecting power to said integrated circuit;

disabling any external clock signal to said integrated circuit; and

reconnecting power to said integrated circuit.

52. A method according to claim 47, wherein said step of analyzing said electromagnetic emissions includes determining whether said electromagnetic emissions are below a predetermined RFI level.

53. A method according to claim 47, wherein:

said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies; and

said step of analyzing said electromagnetic emissions includes

identifying frequencies corresponding to amplitudes greater than a predetermined amplitude, and

comparing said identified frequencies to a predetermined set of frequencies to determine whether one or more clocks of said integrated circuit are operating properly.

54. A method according to claim 47, wherein:

said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies; and

said step of analyzing said electromagnetic emissions includes

identifying frequencies corresponding to amplitudes greater than a predetermined amplitude, and

comparing said identified frequencies to sets of frequencies associated with known devices to determine whether any of said known devices are embedded in said integrated circuit.

55. A method according to claim 47, wherein said step of measuring said electromagnetic emissions includes measuring said electromagnetic emissions at several different locations with respect to said integrated circuit.

56. An electronically readable medium having code embodied therein for causing an electronic device to perform the method of claim 47.

57. A method for determining the internal operation of an integrated circuit comprising:

measuring electromagnet emissions from said integrated circuit;

configuring said integrated circuit prior to said step of measuring said electromagnetic emissions; and

analyzing said electromagnetic emissions; and

wherein said step of configuring said integrated circuit includes re-enabling a disabled external clock signal to said integrated circuit while power is supplied to said integrated circuit.

58. A method according to claim 57, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF probe.

59. A method A method according to claim 58, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF close end probe.

60. A method according to claim 57, wherein said step of configuring said integrated circuit includes placing said integrated circuit in its normal operating mode.

61. A method according to claim 60, wherein said step of placing said integrated circuit chip in its normal operating mode includes providing power and any external clock signal to said integrated circuit.

62. A method according to claim 57, wherein said step of configuring said integrated circuit includes:

providing power to said integrated circuit; and

disabling any external clock signal to said integrated circuit prior to re-enabling said external clock signal.

63. A method according to claim 62, wherein said step of disabling any external clock signal to said integrated circuit includes:

disconnecting power to said integrated circuit;

disabling any external clock signal to said integrated circuit; and

reconnecting power to said integrated circuit.

64. A method according to claim 57, further comprising:

reconfiguring said integrated circuit after said step of measuring said electromagnetic emissions by disconnecting power to said integrated circuit, disabling any external clock signal to said integrated circuit, and reconnecting power to said integrated circuit; and

remeasuring said electromagnetic emissions from said integrated circuit after reconfiguring said integrated circuit.

65. A method according to claim 64, further comprising:

reconnecting any external clock signal to said integrated circuit following said step of remeasuring said electromagnetic emissions; and

remeasuring said electromagnetic emissions from said integrated circuit a second time after said step of reconnecting any external clock signal.

66. A method according to claim 57, wherein said step of analyzing said electromagnetic emissions includes determining whether said electromagnetic emissions are below a predetermined RFI level.

67. A method according to claim 57, wherein:

said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies; and

said step of analyzing said electromagnetic emissions includes identifying frequencies corresponding to amplitudes greater than a predetermined amplitude.

68. A method according to claim 67, wherein said step of analyzing said electromagnetic emissions includes comparing said identified frequencies to a predetermined set of frequencies to determine whether one or more clocks of said integrated circuit are operating properly.

69. A method according to claim 67, wherein said step of analyzing said electromagnetic emissions includes comparing said identified frequencies to sets of frequencies associated with known devices to determine whether any of said known devices are embedded in said integrated circuit.

70. A method according to claim 67, further comprising:

disabling any external clock signal to said integrated circuit alter said step of measuring said electromagnetic emissions from said integrated circuit;

remeasuring said electromagnetic emissions from said integrated circuit while said external clock signal is disabled;

identifying frequencies corresponding to amplitudes greater than said predetermined amplitude in said remeasured electromagnetic emissions; and

comparing said identified frequencies of said measured electromagnetic emissions with said identified frequencies of said remeasured electromagnetic emissions.

71. A method according to claim 57, wherein said step of measuring said electromagnetic emissions includes measuring said electromagnetic emissions at several different locations with respect to said integrated circuit.

72. An electronically readable medium having code embodied therein for causing an electronic device to perform the method of claim 57.

73. A method for determining the internal operation of an integrated circuit comprising:

measuring electromagnet emissions from said integrated circuit; and

configuring said integrated circuit by supplying power and any external clock signal to said integrated circuit prior to measuring said electromagnetic emissions;

reconfiguring said integrated circuit after said step of measuring said electromagnetic emissions by disconnecting power to said integrated circuit, disabling any external clock signal to said integrated circuit, and reconnecting power to said integrated circuit;

remeasuring said electromagnetic emissions from said integrated circuit after reconfiguring said integrated circuit; and

analyzing said electromagnetic emissions.

74. A method according to claim 73, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF probe.

75. A method A method according to claim 74, wherein said step of measuring electromagnetic emissions from said integrated circuit includes using an RF close end probe.

76. A method according to claim 73, wherein said step of configuring said integrated circuit includes placing said integrated circuit in its normal operating mode.

77. A method according to claim 73, wherein said step of configuring said integrated circuit includes re-enabling a disabled external clock signal to said integrated circuit while power is supplied to said integrated circuit.

78. A method according to claim 73, further comprising:

reconnecting any external clock signal to said integrated circuit following said step of remeasuring said electromagnetic emissions; and

remeasuring said electromagnetic emissions from said integrated circuit a second time after said step of reconnecting any external clock signal.

79. A meted according to claim 73, wherein said step of analyzing said electromagnetic emissions includes determining whether said electromagnetic emissions are below a predetermined RFI level.

80. A method according to claim 73, wherein:

said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies; and

said step of analyzing said electromagnetic emissions includes

identifying frequencies corresponding to amplitudes greater than a predetermined amplitude, and

comparing said identified frequencies to a predetermined set of frequencies to determine whether one or more clocks of said integrated circuit are operating properly.

81. A method according to claim 73, wherein:

said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies; and

said step of analyzing said electromagnetic emissions includes

identifying frequencies corresponding to amplitudes greater than a predetermined amplitude, and

comparing said identified frequencies to sets of frequencies associated with known devices to determine whether any of said known devices are embedded in said integrated circuit.

82. A method according to claim 73, wherein said step of measuring electromagnetic emissions includes measuring the amplitude of said electromagnetic emissions over a range of frequencies, and said step of analyzing said electromagnetic emissions includes identifying frequencies corresponding to amplitudes greater than a predetermined amplitude, said method further comprising:

identifying frequencies corresponding to amplitudes greater than said predetermined amplitude in said remeasured electromagnetic emissions; and

comparing said identified frequencies of said measured electromagnetic emissions with said identified frequencies of said remeasured electromagnetic emissions.

83. A method according to claim 73, wherein said step of measuring said electromagnetic emissions includes measuring said electromagnetic emissions at several different locations with respect to said integrated circuit.

84. An electronically readable medium having code embodied therein for causing an electronic device to perform the method of claim 73.

85. An apparatus for determining the internal operation of an integrated circuit, comprising:

a probe for sensing electromagnetic radiation from said integrated circuit; and

a spectrum capture device operative to convert said electromagnetic radiation sensed by said probe into electronic data; and

a spectrum analyzer operative to process said electronic data to provide information about the internal operation of said integrated circuit; and

wherein

said spectrum capture device is operative to capture a first set of spectrum data from said integrated circuit and a second set of spectrum data from said integrated circuit;

said spectrum analyzer is operative to compare said first set of spectrum data to said second set of spectrum data to identify at least one predetermined difference; and

said spectrum capture device is operative to selectively disable an external clock signal to said integrated circuit during the capture of one of said first set of spectrum data and said second set of spectrum data.

86. An apparatus according to claim 85, further comprising a display for presenting said data from said spectrum analyzer.

87. An apparatus according to claim 86, wherein said spectrum analyzer is operative to present said data on said display in the form of an amplitude versus frequency graph.

88. An apparatus according to claim 85, wherein said spectrum capture device includes a spectrum capture routine and said spectrum analyzer includes a spectrum analyzer routine;

and said apparatus further comprising;

a processing unit for executing code and processing data; and

memory for storing said code, said code including said spectrum capture routine and said spectrum analyzer routine.

89. An apparatus according to claim 88, wherein said spectrum capture device is further operative to control the position of said probe.

90. An apparatus according to claim 85, wherein said spectrum capture device is further operative to selectively interrupt electrical power to said integrated circuit.

91. An apparatus according to claim 85, wherein said spectrum capture device is further operative to selectively enable and disable an external clock signal to said integrated circuit.

92. An apparatus according to claim 85, wherein said spectrum capture device is operative to store said electronic data as records indicative of an electromagnetic spectrum emitted by said integrated circuit.