Resonant micro-electro-mechanical system with analog driving

An integrated micro-electro-mechanical gyroscope, comprising:

• a microstructure having a first mass which is free to oscillate along a first axis;
• a driving device coupled to said first mass for maintaining said first mass in oscillation at a resonance frequency, said driving device including:
• a differential sense amplifier supplying first signals indicative of a velocity of oscillation of said first mass;
• an actuation and control stage supplying second signals for driving said first mass on the basis of said first signals;
• and
• a filter, of a high-pass type, connected between said differential sense amplifier and said actuation and control stage and having a bandpass including said resonance frequency;
• and
• an inertial sensor mechanically coupled to said first mass so as to be fixedly drawn along by said first mass along said first axis and having an axis of detection perpendicular to said first axis.

An integrated micro-electro-mechanical system, comprising:

• a microstructure including a first mass constrained to oscillate along a first axis and a second mass constrained to oscillate along the first axis and a second axis, the second mass coupled to the first mass;
• an analog driving device coupled to the first mass in a feedback loop for maintaining the first mass in oscillation at a resonance frequency and including:
• a differential sense amplifier electrically coupled to the first mass, the differential sense amplifier adapted to receive first signals indicative of a velocity of the first mass and generate second signals indicative of the velocity of the first mass;
• and
• a high-pass filter coupled to the differential sense amplifier and configured to filter the second signals, the high-pass filter having a bandpass that includes the resonance frequency;
• and
• an analog reading device coupled to the second mass for detecting motion of the second mass along the second axis.

A method for driving a resonant micro-electro-mechanical system, comprising the steps of:

• receiving reading currents indicative of an oscillation velocity of a driving mass constrained to move along a first axis, the driving mass being coupled to a sensing mass and the sensing mass being configured to move along the first axis and a second axis;
• convening the reading currents to reading voltages indicative of the oscillation velocity of the driving mass;
• filtering the reading voltages to eliminate offset voltages;
• generating a control voltage based upon the filtered reading voltages and a reference voltage;
• and
• amplifying the filtered reading voltages via a variable gain amplifier to generate driving signals;
• and
• applying the driving signals to the driving mass to maintain the driving mass in oscillation along the first axis at a resonance frequency.

A system, comprising:

• a microstructure having a mass which is free to oscillate in accordance with a degree of freedom;
• and
• a driving means for maintaining the mass in oscillation at a resonance frequency, coupled to the mass and including:
• means for supplying a velocity signal indicative of a velocity of oscillation of the mass;
• means for supplying a driving signal for driving the mass;
• and
• means for filtering the velocity signal coupled between the means for supplying the velocity signal and the means for supplying the driving signal.