Active protection device for protecting circuit against mechanical and electromagnetic attack

1. An active protection device for protecting an integrated circuit containing at least one layer of active semiconductor material against an electromagnetic attack, eventually after a mechanical or chemical attack, wherein the active protection device comprises:

at least one layer of active semiconductor material, this layer being electrically connected to contact pads for interfacing external electronic circuits

at least one field generator able to create a magnetic field next to the circuit to protect,

at least one magnetic sensor able to measure the value of the magnetic field,

an intrusion checking device, called integrity circuit, connected either to the at least one magnetic sensor and to the one layer of active semiconductor material from the circuit to protect and/or external electronic circuits, said integrity circuit being able to perform an emergency safety process in order to modify the functioning of the circuit to protect and/or to send an electrical signal to inform an attack happens or happened if the measured value of the magnetic field made by the magnetic sensor is out of a predetermined range, said range varies according to the value of the induced magnetic field.

2. An active protection device according to claim 1 , wherein the at least one field generator are at least two, and are attached on the same side of the circuit to protect.

3. An active protection device according to claim 1 , wherein the at least one field generator are at least two, and are attached on both sides of the circuit to protect.

4. An active protection device according to claim 1 , wherein the at least one field generator is made of a permanent magnet.

5. An active protection device according to claim 4 , wherein the permanent magnet is made of a magnetic material chosen among the group of magnetic material comprising the Ferrites, CoPt, SmCo 5 , and NdFeB material.

6. An active protection device according to claim 1 , wherein the at least one field generator is made of a coil driven with a continuous current supplied by an electronic driver.

7. An active protection device according to claim 1 , wherein the at least one field generator is made of a coil driven with an alternating current supplied by an electronic driver, and the signals delivered by the at least one magnetic sensor are processed by a demodulator before being compared to a magnetic range in the integrity circuit.

8. An active protection device according to claim 7 , wherein the electronic driver supplying alternating current in the coil is frequency adjustable, and its frequency is determined by a frequency controller, an electric signal function of this frequency being sent to the demodulator.

9. An active protection device according to claim 1 , wherein the at least one magnetic sensor is a Hall-effect type sensor.

10. An active protection device according to claim 1 , wherein the at least one magnetic sensor is a magnetoresistance type sensor.

11. An active protection device according to claim 1 , wherein the at least one magnetic sensors are at least two, and separated by a distance range between 50 μm and 150 μm.

12. An active protection device according to claim 1 , wherein the number of the at least one magnetic sensor is even, and those sensors are half bridge or bridge connected.

13. An active protection device according to claim 12 , wherein the number of the at least one magnetic sensor is included in the range from 4 to 10.

14. An active protection device according to claim 1 , wherein the emergency safety process consists in the emission of a trigger toward either the circuit to protect or toward an external electronic circuit via an electrical contact pad.

15. An active protection device according to claim 1 , wherein the emergency safety process consists in the processing of a specific sequence that modifies the functioning of the circuit to protect.

16. An active protection device according to claim 15 , wherein the specific sequence inhibits at least one functionality of the circuit to protect.

17. An active protection device according to claim 15 , wherein the circuit to protect contains at least a memory circuit, and the specific sequence erases at least a part of this memory circuit.

18. An active protection device according to claim 15 , wherein the circuit to protect contains at least a processor, and the specific sequence modifies at least a part of this processor's program.

19. An active protection device according to claim 1 , wherein the field generator is made of a magnetic material covering the places generating the stronger or the most informative electrical signals.

20. An active protection device according to claim 2 , wherein:

the at least one field generator are at least two, and are attached on both sides of the circuit to protect;

the at least one field generator is made of a permanent magnet;

the at least one field generator is made of one of a coil driven with a continuous current supplied by an electronic driver and a coil driven with an alternating current supplied by an electronic driver, and the signals delivered by the at least one magnetic sensor are processed by a demodulator before being compared to a magnetic range in the integrity circuit;

the electronic driver supplying alternating current in the coil is frequency adjustable, and its frequency is determined by a frequency controller, an electric signal function of this frequency being sent to the demodulator;

the at least one magnetic sensor is a Hall-effect type sensor;

the at least one magnetic sensor is a magnetoresistance type sensor;

the at least one magnetic sensors are at least two, and separated by a distance range between 50 μm and 150 μm;

the number of the at least one magnetic sensor is even, and those sensors are half bridge or bridge connected;

the number of the at least one magnetic sensor is included in the range from 4 to 10;

the emergency safety process consists in the emission of a trigger toward either the circuit to protect or toward an external electronic circuit via an electrical contact pad;

the emergency safety process consists in the processing of a specific sequence that modifies the functioning of the circuit to protect;

the circuit to protect contains one of at least a memory circuit, and the specific sequence erases at least a part of this memory circuit and at least a processor, and the specific sequence modifies at least a part of this processor's program; and

the field generator is made of a magnetic material covering the places generating the stronger or the most informative electrical signals.