Flexible printed cable and information processing device

1. A flexible printed cable, comprising:

a signal line pattern configured to transmit a communication signal;

an upper signal protective line pattern which is opposed to an upper surface of the signal line pattern and a lower signal protective line pattern which is separate from the upper signal protective line pattern and is opposed to a lower surface of the signal line pattern, wherein each of the upper signal protective line pattern and the lower signal protective line pattern has a width equal to or larger than a width of the signal line pattern,

wherein the signal protective line patterns are provided overlapping along the signal line pattern within a first region that requires tamper resistance,

wherein, in at least the first region of the cable, each portion of the signal line pattern is disposed between respective overlapping portions of the upper signal protective line pattern and the lower signal protective line pattern, and

wherein different potentials are applied to the upper signal protective line pattern and the lower signal protective line pattern; and

an insulating layer separating the signal line pattern, the upper signal protective line pattern, and the lower signal protective line pattern from one another and covering the signal line pattern, the upper signal protective line pattern, and the lower signal protective line pattern.

2. An information processing device, comprising:

the flexible printed cable according to claim 1 ; and

a control unit comprising:

a detector which detects a change in potential of the signal protective line patterns; and

an illegal connection information generator connected to the detector, which generates illegal connection information for notifying that illegal connection has been made when the detector detects the change in the potential.

3. The information processing device according to claim 2 , wherein, when the illegal connection information is received, the information processing device performs processing of stopping an operation of a unit connected to the signal line pattern and/or processing of erasing important information owned by the information processing device.

4. The information processing device according to claim 2 , further comprising:

at least one power source connected to the upper signal protective line pattern and the lower signal protective line pattern via a first resistive section, and configured to apply a voltage, different from a voltage of the signal line pattern, to the upper signal protective line pattern and the lower signal protective line pattern;

a ground section, connected to the upper signal protective line pattern and the lower signal protective line pattern via a second resistive section, which grounds the signal protective line patterns.

5. The information processing device according to claim 4 , wherein:

the upper signal protective line pattern and the lower signal protective line pattern are configured to have different potentials.

6. The information processing device according to claim 5 , wherein:

the upper signal protective line pattern is connected to the power source via a first power source side resistive element of the first resistive section, and is connected to the ground section via a first ground side resistive element of the second resistive section;

the lower signal protective line pattern is connected to the power source via a second power source side resistive element of the first resistive section, and is connected to the ground section via a second ground side resistive element of the second resistive section; and

the first power source side resistive element, the second power source side resistive element, the first ground side resistive element, and the second ground side resistive element have electrical resistance values so that a potential of the upper signal protective line pattern between the first power source side resistive element and the first ground side resistive element has a value closer to a potential of the ground section than a potential of the lower signal protective line pattern between the second power source side resistive element and the second ground side resistive element.

7. The information processing device according to claim 2 , wherein:

a plurality of the signal line patterns are provided; and

said information processing device is configured so that different potentials are applied to adjacent ones of the signal protective line patterns.

8. The information processing device according to claim 4 , wherein the power source comprises a power source for applying a constant voltage or a dynamically changing voltage.

9. A flexible printed cable, comprising:

a signal line pattern configured to transmit a communication signal;

a signal protective line pattern which is opposed to only any one of an upper surface and a lower surface of the signal line pattern, wherein the signal protective line pattern has a width equal to or larger than a width of the signal line pattern,

wherein the signal protective line pattern is provided overlapping along the signal line pattern within a first region that requires tamper resistance, and

wherein, in at least the first region of the cable, each portion of the signal line pattern is disposed between an overlapping portion of the signal protective line pattern and the other of the upper surface and the lower surface of the signal line pattern; and

an insulating layer separating the signal line pattern and the signal protective line pattern from one another and covering the signal line pattern and the signal protective line pattern.

10. An information processing device, comprising:

the flexible printed cable according to claim 9 ; and

a control unit comprising:

a detector which detects a change in potential of the signal protective line pattern; and

an illegal connection information generator connected to the detector, which generates illegal connection information for notifying that illegal connection has been made when the detector detects the change in the potential.