DRIVING CIRCUIT FOR CONTROLLING A MEMS OSCILLATOR OF RESONANT TYPE
DRIVE
December 29, 2022
A driving circuit for controlling a MEMS oscillator includes a digital conversion stage to acquire a differential sensing signal indicative of a displacement of a movable mass of the MEMS oscillator, and to convert the differential sensing signal of analog type into a digital differential signal of digital type. Processing circuitry is configured to generate a digital control signal of digital type as a function of the comparison between the digital differential signal and a differential reference signal indicative of a target amplitude of oscillation of the movable mass which causes the resonance of the MEMS oscillator. An analog conversion stage includes a ΣΔ DAC and is configured to convert the digital control signal into a PDM control signal of analog type. A filtering stage of low-pass type, by filtering the PDM control signal, generates a control signal for controlling the amplitude of oscillation of the movable mass.
Discussion in the ATmosphere