Magnetic inertial sensor and method for operating the same

A portable system, comprising:

• a processor;
• an inertial sensor coupled to the processor, the inertial sensor including:
• a body of semiconductor material having a first surface and a second surface, the body including:
• an excitation coil;
• a first sensing coil extending at a first distance from the excitation coil along a first axis;
• a suspended mass including a magnetic-field concentrator, the suspended mass extending above the first surface and being magnetically coupled to the excitation coil and to the first sensing coil, and configured to displace by way of inertia;
• and
• a supply and sensing circuit, electrically coupled to the excitation coil and to the first sensing coil, and configured to generate a time-variable flow of electric current through the excitation coil to generate a magnetic field that, in use, interacts with said magnetic-field concentrator to induce an electrical quantity in the first sensing coil, the supply and sensing circuit being configured to measure a value of said electrical quantity induced in the first sensing coil to detect a quantity associated to the displacement of the suspended mass.

A method, comprising:

• operating an inertial sensor that includes a body having a first surface and a second surface, the body including an excitation coil and a first sensing coil both electrically coupled to a supply and sensing circuit, the first sensing coil extending at a first distance from the excitation coil along a first axis, the sensor including a suspended mass that has a magnetic-field concentrator extending above the first surface, the operating including:
• coupling magnetically the suspended mass to the excitation coil and to the first sensing coil;
• generating a magnetic field by generating a time-variable flow of electric current in the excitation coil;
• obtaining an interaction between the magnetic field and the magnetic-field concentrator;
• inducing an electrical quantity in the first sensing coil;
• measuring a value of said electrical quantity induced in the first sensing coil;
• and
• obtaining, on the basis of the measured value of said electrical quantity, a quantity associated with a displacement of the suspended mass.