Secure touchscreen device

1. A secure touchscreen assembly comprising:

a first patterned conductive layer comprising a plurality of first traces, each first trace comprising a conductive pad at each end;

a second patterned conductive layer comprising a plurality of second traces, each second trace comprising a conductive pad at each end;

tamper sensing circuitry that detects a tamper by detecting a change in conductivity in one of the traces in the first patterned conductive layer and the second patterned conductive layer;

touch sensing circuitry that detects a touch; and

a switch that selectably electrically couples the tamper sensing circuitry to the conductive pads for at least one of the plurality of first traces and the plurality of second traces, or electrically couples the touch sensing circuitry to one of the conductive pads for each of the plurality of first traces and the plurality of second traces at a given time.

2. The secure touchscreen assembly of claim 1 , wherein the conductive pad for each of the plurality of first traces and the plurality of second traces that is not electrically coupled to the touch sensing circuitry floats when the switch electrically couples the touch sensing circuitry to one of the conductive pads for each of the plurality of first traces and the plurality of second traces.

3. The secure touchscreen of claim 1 , wherein the change in conductivity comprises one of an open circuit and a short circuit.

4. The secure touchscreen of claim 1 , wherein the first patterned conductive layer further comprises a first tamper sensing grid that is disposed in areas of the first conductive layer where the plurality of first traces are not present and is not in physical contact with the plurality of first traces; and

wherein the touch sensing circuitry is coupled to the first tamper sensing grid and further detects the tamper by detecting a change in conductivity in the first tamper sensing grid.

5. The secure touchscreen of claim 4 , wherein the second patterned conductive layer further comprises a second tamper sensing grid that is disposed in areas of the second conductive layer where the plurality of second traces are not present and is not in physical contact with the plurality of second traces; and

wherein the touch sensing circuitry is coupled to the second tamper sensing grid and further detects the tamper by detecting a change in conductivity in the second tamper sensing grid.

6. The secure touchscreen of claim 1 , further comprising:

an electrically insulative layer disposed between the first patterned conductive layer and the second patterned conductive layer.

7. A secure touchscreen assembly comprising:

a first patterned conductive layer comprising a plurality of first traces, each first trace comprising a conductive pad at each end;

a second patterned conductive layer comprising a plurality of second traces, each second trace comprising a conductive pad at each end;

tamper sensing circuitry that detects a tamper by detecting a change in conductivity in one of the plurality of first traces or in one of the plurality of second traces;

touch sensing circuitry that detects a touch; and

a switch that selectably electrically couples the tamper sensing circuitry to the conductive pads for at least one of the plurality of first traces and the plurality of second traces, or electrically couples the touch sensing circuitry to one of the conductive pads for each of the plurality of first traces and the plurality of second traces at a given time;

wherein when the tamper sensing circuitry is electrically coupled to the conductive pads for at least one of the plurality of first traces and a change in conductivity is detected in one of the plurality of first traces, the tamper sensing circuitry detects a tamper; and

wherein when the tamper sensing circuitry is electrically coupled to the conductive pads for at least one of the plurality of second traces and a change in conductivity is detected in one of the plurality of second traces, the tamper sensing circuitry detects a tamper.

8. The secure touchscreen assembly of claim 7 , wherein the conductive pad for each of the plurality of first traces and the plurality of second traces that is not electrically coupled to the touch sensing circuitry floats when the switch electrically couples the touch sensing circuitry to one of the conductive pads for each of the plurality of first traces and the plurality of second traces.

9. The secure touchscreen of claim 7 , wherein the change in conductivity comprises one of an open circuit and a short circuit.

10. The secure touchscreen of claim 7 , wherein the first patterned conductive layer further comprises a first tamper sensing grid that is disposed in areas of the first conductive layer where the plurality of first traces are not present and is not in physical contact with the plurality of first traces; and

wherein the touch sensing circuitry is coupled to the first tamper sensing grid and further detects the tamper by detecting a change in conductivity in the first tamper sensing grid.

11. The secure touchscreen of claim 10 , wherein the second patterned conductive layer further comprises a second tamper sensing grid that is disposed in areas of the second conductive layer where the plurality of second traces are not present and is not in physical contact with the plurality of second traces; and

wherein the touch sensing circuitry is coupled to the second tamper sensing grid and further detects the tamper by detecting a change in conductivity in the second tamper sensing grid.

12. The secure touchscreen of claim 7 , further comprising:

an electrically insulative layer disposed between the first patterned conductive layer and the second patterned conductive layer.