Variable capacitance electronic device and microelectromechanical device incorporating such electronic device

A microelectromechanical device, comprising:

• an inertial sensor;
• a charge amplifier coupled to the inertial sensor;
• and
• a compensation stage, wherein the compensation stage comprises a variable capacitance electronic device that includes:
• a capacitive component, having a variable capacitance;
• a control stage, coupled to the capacitive component configured to control the variable capacitance, based on a reference signal, having a reference frequency, and on an excitation signal, having an excitation frequency that is a multiple of the reference frequency;
• wherein the capacitive component comprises a variable capacitive network having a plurality of switched capacitors, each of which is selectively switchable between a first configuration, in which the switched capacitor is connected between a first signal terminal and a second signal terminal of the capacitive component, and a second configuration, in which the switched capacitor is connected to at most one of the first signal terminal and the second signal terminal;
• the control stage comprises a logic module, coupled to the variable capacitive network and configured to periodically switch each switched capacitor between the first and the second configuration, based on the reference signal;
• and
• a sign circuit, coupled to the capacitive component and configured to provide a control signal having concordant edges with the excitation signal in one half-period of each cycle of the reference signal and discordant edges with the excitation signal in the other half-period of each cycle of the reference signal.

A system, comprising:

• a control unit, and
• a device coupled to the control unit, the device comprising:
• an inertial sensor;
• a charge amplifier coupled to the inertial sensor;
• and
• a compensation stage, wherein the compensation stage comprises a variable capacitance electronic device that includes:
• a capacitive component, having a variable capacitance;
• a control stage, coupled to the capacitive component configured to control the variable capacitance, based on a reference signal, having a reference frequency, and on an excitation signal, having an excitation frequency that is a multiple of the reference frequency;
• wherein the capacitive component comprises a variable capacitive network having a plurality of switched capacitors, each of which is selectively switchable between a first configuration, in which the switched capacitor is connected between a first signal terminal and a second signal terminal of the capacitive component, and a second configuration, in which the switched capacitor is connected to at most one of the first signal terminal and the second signal terminal;
• the control stage comprises a logic module, coupled to the variable capacitive network and configured to periodically switch each switched capacitor between the first and the second configuration, based on the reference signal;
• and
• a sign circuit, coupled to the capacitive component and configured to provide a control signal having concordant edges with the excitation signal in one half-period of each cycle of the reference signal and discordant edges with the excitation signal in the other half-period of each cycle of the reference signal.

An electrical wafer sorting test apparatus for a driving device of a microelectromechanical gyroscope, comprising:

• a semiconductor wafer incorporating a driving device, connectable to a microelectromechanical gyroscope configured to maintain a driving mass of the microelectromechanical gyroscope in oscillation at a resonance frequency;
• and
• a variable capacitance electronic device that comprises:
• a capacitive component, having a variable capacitance;
• a control stage, coupled to the capacitive component configured to control the variable capacitance, based on a reference signal, having a reference frequency, and on an excitation signal, having an excitation frequency that is a multiple of the reference frequency;
• wherein the capacitive component comprises a variable capacitive network having a plurality of switched capacitors, each of which is selectively switchable between a first configuration, in which the switched capacitor is connected between a first signal terminal and a second signal terminal of the capacitive component, and a second configuration, in which the switched capacitor is connected to at most one of the first signal terminal and the second signal terminal;
• the control stage comprises a logic module, coupled to the variable capacitive network and configured to periodically switch each switched capacitor between the first and the second configuration, based on the reference signal;
• and
• a sign circuit, coupled to the capacitive component and configured to provide a control signal having concordant edges with the excitation signal in one half-period of each cycle of the reference signal and discordant edges with the excitation signal in the other half-period of each cycle of the reference signal;
• and wherein the capacitive component is connected to an input terminal of the driving device.

A method of forming a microelectromechanical device, the method comprising:

• forming an inertial sensor;
• forming a charge amplifier coupled to the inertial sensor;
• forming a compensation stage having a variable capacitance electronic device, wherein forming the compensation stage includes:
• forming a capacitive component, having a variable capacitance;
• forming a control stage, coupled to the capacitive component configured to control the variable capacitance, based on a reference signal, having a reference frequency, and on an excitation signal, having an excitation frequency that is a multiple of the reference frequency;
• forming a variable capacitive network in the capacitive component, the variable capacitive network having a plurality of switched capacitors, each of which is selectively switchable between a first configuration, in which the switched capacitor is connected between a first signal terminal and a second signal terminal of the capacitive component, and a second configuration, in which the switched capacitor is connected to at most one of the first signal terminal and the second signal terminal;
• forming a logic module in the control stage, coupled to the variable capacitive network and configured to periodically switch each switched capacitor between the first and the second configuration, based on the reference signal;
• and
• forming a sign circuit, coupled to the capacitive component and configured to provide a control signal having concordant edges with the excitation signal in one half-period of each cycle of the reference signal and discordant edges with the excitation signal in the other half-period of each cycle of the reference signal.