Microelectromechanical gyroscope with self-test function and control method

A method for controlling a microelectromechanical gyroscope, comprising:

• providing a microstructure including a first mass oscillatable along a first axis at a driving frequency and a second mass;
• coupling the second mass to the first mass so that, the first mass configured to move the second mass is drawn along the first axis by the first mass and oscillates along a second axis in response to a rotation of the microstructure at the driving frequency;
• feedback controlling a velocity of the first mass to maintain the first mass in oscillation at a driving frequency;
• and
• performing a self-test by applying an electrostatic force to the second mass via self-test terminals at the driving frequency by, the self-test including alternatingly coupling the self-test terminals to a supply line and to a ground line to and moving the second mass along the second axis by alternatingly receive receiving a supply voltage and a ground voltage so as to move the second mass along the second axis at the self-test terminals.

A circuit adapted configured for use with a microelectromechanical gyroscope having a first mass and a second mass oscillatable in response to oscillations of the first mass, the circuit comprising:

• a driving circuit coupled to the first mass to drive the first mass in oscillation at a driving frequency;
• a reading device coupled to the second mass and adapted configured to detect displacements of the second mass;
• and
• a self-test actuation system coupled to the second mass via self-test electrodes and structured to drive the second mass through application of an electrostatic force at a driving frequency by coupling the self-test electrodes alternatingly to a supply voltage and a ground voltage in order to move the second mass.

A system, comprising:

• a control circuit;
• a microelectromechanical gyroscope that comprises coupled to the control circuit, the gyroscope including:
• a microstructure having a first mass configured to oscillate at a driving frequency;
• and
• a second mass coupled to the first mass, the second mass configured to oscillate in response to oscillations of the first mass;
• a driving device comprising:
• a driving circuit coupled to the first mass to drive the first mass in oscillation at a driving frequency;
• a reading device coupled to the second mass and adapted configured to detect displacements of the second mass;
• and
• a self-test actuation system coupled to the second mass and structured to drive the second mass through application of an electrostatic force at a driving frequency by coupling, the self-test actuation system configured to couple the second mass alternatingly to a supply voltage line and a ground voltage line in order to move drive the second mass during a self-test.

A microelectromechanical gyroscope, comprising:

• a microstructure, including a first mass and a second mass, wherein the first mass is oscillatable along a first axis and the second mass is coupled to the first mass so as to be drawn along the first axis by the first mass and to oscillate along a second axis perpendicular to the first axis in response to a rotation of the microstructure;
• a driving device coupled to the microstructure to maintain the first mass in oscillation at a driving frequency;
• a reading device structured to detect displacements of the second mass along the second axis;
• and
• a self-test actuation system coupled to the second mass via self-test terminals and structured to apply an electrostatic force at the driving frequency so as to move the second mass along the second axis, the self-test actuation system structured to be selectively enabled in a first operating mode and disabled in a second operating mode, and wherein in the second operating mode the self-test terminals are connected to a reference line issuing a constant reference voltage.

A device, comprising:

• a substrate;
• a driving mass suspended above the substrate and configured to oscillate at a driving frequency;
• a sensing mass suspended above the substrate, elastically coupled to the driving mass, and configured to move in response to the driving mass, the sensing mass including:
• detection electrodes;
• and
• actuation electrodes;
• and
• a self-test module coupled to the sensing mass and configured to move the sensing mass at the driving frequency during a self-test mode, the self-test module configured to alternatingly connect self-test terminals to a supply line and a ground line to alternatingly receive a supply voltage and a ground voltage.