Patent ID: 9194703
Filing Date: 2015-11-24
Classification: G01C,H03B

Abstract:
1. An electronic drive circuit for a MEMS type resonator device, the electronic drive circuit being connected to at least one resonator of the resonator device, the resonator including a mass connected to a structure of the device by a spring and a damping element, an actuation element for setting the mass in motion in one direction on the basis of an actuation signal, which is supplied by the electronic circuit, and a detection element for detecting the motion of the mass processed in the electronic circuit to adapt at least one oscillation amplitude level of the moving mass, wherein the electronic drive circuit includes a conversion means connected to the detection element to supply a mathematical derivative signal relating to the oscillation of the moving mass, a comparison means for comparing an amplitude level of the mathematical derivative signal and a defined reference amplitude for supplying an amplitude level control signal, and a decision unit, which is connected to the conversion means and to the comparison means, and which is configured to supply an actuation signal in digital form to the actuation element, said actuation signal being formed of a series of rectangular pulses arranged and determined on the basis of the mathematical derivative signal and of the control signal to increase or decrease or maintain the oscillation amplitude of the moving mass as a function of the defined reference amplitude, wherein the conversion means is a current-voltage converter receiving a detection current from the detection element and supplying the mathematical derivative signal, which is a sinusoidal voltage signal, wherein the detection element is a detection capacitor, whose first electrode is connected to the moving mass and whose second electrode is connected to the current-voltage converter, and wherein the current-voltage converter includes an amplifier a negative input of which is connected to the second electrode of the detection capacitor and a positive electrode receives a reference voltage, a resistor being placed between the negative input and an output of the amplifier, which supplies the mathematical derivative signal in sinusoidal form referenced relative to the reference voltage with a positive alternation above the reference voltage and a negative alternation below the reference voltage.