READING CIRCUIT FOR A MULTI-AXIS MEMS GYROSCOPE HAVING DETECTION DIRECTIONS INCLINED WITH RESPECT TO THE REFERENCE AXES, AND CORRESPONDING MULTI-AXES MEMS GYROSCOPE

• US 20130180331A1
• Filed: 03/07/2013
• Published: 07/18/2013
• Est. Priority Date: 11/26/2008
• Status: Active Grant

• Current Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Original Assignee: STMicroelectronics SRL (STMicroelectronics NV)
• Inventors: Prandi, Luciano, Caminada, Carlo
• Granted Patent: US 8,813,565 B2
• Time in Patent Office: Days
• US Class Current: 73/504.02
• CPC Class Codes: G01C 19/56 Turn-sensitive devices using vibrating masses, e.g. vibratory angular rate sensors based on Coriolis forces
• CPC Class Codes: G01C 19/5712 the devices involving a micromechanical structure

Abstract

A multi-axis gyroscope includes a microelectromechanical structure configured to rotate with respective angular velocities about respective reference axes, and including detection elements, which are sensitive in respective detection directions and generate respective detection quantities as a function of projections of the angular velocities in the detection directions. The gyroscope including a reading circuit that generates electrical output signals, each correlated to a respective one of the angular velocities, as a function of the detection quantities. The reading circuit includes a combination stage that combines electrically with respect to one another electrical quantities correlated to detection quantities generated by detection elements sensitive to detection directions different from one another, so as to take into account a non-zero angle of inclination of the detection directions with respect to the reference axes.

Claims

1. A device, comprising:

a multi-axis gyroscope configured to rotate in response to angular velocities about a first reference axis and a second reference axis, the gyroscope including;

a first pair and a second pair of detection elements, each pair being positioned along a first and second detection direction, respectively, the first and second directions being different from one another and being at a non-zero angle of inclination from the first and second reference axes, and each detection element being configured to generate a detection signal as a function of projections of said angular velocities in said first and second detection directions;

a reading circuit coupled to the gyroscope, the reading circuit including;

a combination stage configured to combine the detections signals of one of the first pair of detection elements with one of the second pair of detection elements to produce a first and second combination signal, the combination stage configured to account for the non-zero angle of inclination of said first and second detection directions with respect to said reference axes; and

an output stage configured to provide a first and a second electrical output signal based on the first and second combination signals received from the combination stage, the first output signal being correlated to the angular velocity about the first reference axis and the second output signal being correlated to the angular velocity about the second reference axis.

2. The device of claim 1, wherein the reading circuit includes a plurality of inputs electrically connected between outputs from the gyroscope and inputs of the combination stage.

3. The device of claim 2, wherein the combination stage is configured to receive timing signals to short circuit in pairs one of the detection elements from the first pair and one of the detection elements from the second pair.

4. The device of claim 3, wherein the timing signals include a first timing signal and a second timing signal, the combination stage including a plurality of switches configured to receive the first and second timing signals, the plurality of switches being configured to short circuit one of the detection elements from the first pair and one of the detection elements from the second pair in response to the first timing signal and to short circuit the other one of the detection elements from the first pair and the other one of the detection elements from the second pair in response to the second timing signal.

5. The device of claim 4, wherein the combination stage is configured to generate a first combination of charge contributions in response to the first timing signal and a second combination of charge contributions in response to the second timing signal.