CN107037237B - Triaxial capacitive accelerometer and electronic device - Google Patents
Triaxial capacitive accelerometer and electronic device Download PDFInfo
- Publication number
- CN107037237B CN107037237B CN201710333977.9A CN201710333977A CN107037237B CN 107037237 B CN107037237 B CN 107037237B CN 201710333977 A CN201710333977 A CN 201710333977A CN 107037237 B CN107037237 B CN 107037237B
- Authority
- CN
- China
- Prior art keywords
- axis
- capacitance detection
- mass
- capacitive accelerometer
- mass block
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Active
Links
Images
Classifications
-
- G—PHYSICS
- G01—MEASURING; TESTING
- G01P—MEASURING LINEAR OR ANGULAR SPEED, ACCELERATION, DECELERATION, OR SHOCK; INDICATING PRESENCE, ABSENCE, OR DIRECTION, OF MOVEMENT
- G01P15/00—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration
- G01P15/02—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses
- G01P15/08—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values
- G01P15/125—Measuring acceleration; Measuring deceleration; Measuring shock, i.e. sudden change of acceleration by making use of inertia forces using solid seismic masses with conversion into electric or magnetic values by capacitive pick-up
Landscapes
- Physics & Mathematics (AREA)
- General Physics & Mathematics (AREA)
- Pressure Sensors (AREA)
Abstract
The invention discloses a triaxial capacitive accelerometer and an electronic device, comprising: the first mass block and the second mass block are arranged symmetrically, coupled and connected through an elastic structure, and movably arranged on the substrate through at least one fixed anchor point corresponding to the mass block, so that when an acceleration is applied to the triaxial capacitive accelerometer, the mass block generates a motion corresponding to the acceleration; the mass block multiplexing movable structure is fixed on the substrate and used for generating specific capacitance value change with acceleration when the acceleration is applied to the triaxial capacitive accelerometer. The technical scheme provided by the invention is beneficial to the trend of lightness and thinness of the triaxial capacitive accelerometer, and effectively reduces the zero point deviation and the sensitivity deviation of the accelerometer.
Description
Technical Field
The invention relates to the technical field of triaxial capacitive accelerometers, in particular to a triaxial capacitive accelerometer and an electronic device.
Background
Micro-accelerometers manufactured based on Micro-Electro-Mechanical-systems (MEMS) have been increasingly used in a wide variety of fields, such as industry, medical treatment, civil use, and military, due to their advantages, such as small size, low cost, good integration, and excellent performance. At present, the mobile terminal is applied to various products such as mobile terminals, cameras, game pads, navigators and the like, and becomes standard configuration to a certain extent. In the development process, a capacitive type accelerometer, a resistive type accelerometer and a piezoelectric type accelerometer are mainly applied mechanisms, wherein the capacitive type accelerometer is the most popular accelerometer due to the advantages of simple structure, low cost, high sensitivity, high linearity and the like in a low-frequency range. However, the existing triaxial capacitive accelerometer generally sets different mass blocks for different axial capacitance detection areas, and the mass blocks occupy larger area and weight, which is not favorable for the trend of lightness and thinness of the triaxial capacitive accelerometer.
Disclosure of Invention
In view of this, the present invention provides a three-axis capacitive accelerometer and an electronic device, wherein the capacitance detection areas of the three-axis capacitive accelerometer share the first mass block and the second mass block, so as to reduce the number of mass blocks, thereby facilitating the trend of light weight and thinness of the three-axis capacitive accelerometer.
In order to realize the purpose, the technical scheme provided by the invention is as follows:
a three-axis capacitive accelerometer comprising:
the device comprises a first mass block and a second mass block which are symmetrically arranged in structure, wherein the first mass block and the second mass block are coupled and connected through an elastic structure, and the mass blocks are movably arranged on a substrate through at least one fixed anchor point corresponding to the mass blocks and are used for generating motion corresponding to acceleration when the acceleration is applied to the three-axis capacitive accelerometer;
and a plurality of detection areas located in any mass block range, wherein any detection area comprises a detection capacitor consisting of a fixed structure and a movable structure, the mass block is multiplexed with the movable structure, and the fixed structure is fixed on the substrate and used for generating specific capacitance value change with the acceleration when the triaxial capacitive accelerometer applies the acceleration.
Optionally, the mass block includes a first Z-axis capacitance detection area, a second capacitance detection portion, a third capacitance detection portion, and a second Z-axis capacitance detection area, which are arranged along a first direction, where the second capacitance detection portion is provided with a first X-axis capacitance detection area, a first Y-axis capacitance detection area, and a second X-axis capacitance detection area along a second direction, and the third capacitance detection portion is sequentially provided with a third X-axis capacitance detection area, a second Y-axis capacitance detection area, and a fourth X-axis capacitance detection area along the second direction;
wherein the first direction is the first mass-second mass direction, and the second direction intersects the first direction.
Optionally, the mass block corresponding to the first X-axis capacitance detection area, the second X-axis capacitance detection area, the third X-axis capacitance detection area and the fourth X-axis capacitance detection area are all hollow areas;
the X-axis capacitance detection area comprises a first movable structure, a first fixed structure, a second movable structure and a second fixed structure which are arranged along the first direction, wherein the first movable structure and the first fixed structure form a first X-axis detection capacitor, and the second movable structure and the second fixed structure form a second X-axis detection capacitor;
when the acceleration of the X-axis direction is applied to the three-axis capacitive accelerometer, the capacity change of the first X-axis detection capacitor and the capacity change of the second X-axis detection capacitor are opposite.
Optionally, the mass block corresponding to the first Y-axis capacitance detection area and the second Y-axis capacitance detection area are both hollow areas;
the Y-axis capacitance detection area comprises a first movable structure, a first fixed structure, a second movable structure and a second fixed structure which are arranged along the first direction, wherein the first movable structure and the first fixed structure form a first Y-axis detection capacitor, and the second movable structure and the second fixed structure form a second Y-axis detection capacitor;
when the triaxial capacitive accelerometer is applied with acceleration in the Y-axis direction, the capacity change of the first Y-axis detection capacitor and the capacity change of the second Y-axis detection capacitor are opposite.
Optionally, the first Z-axis capacitance detection area and the second Z-axis capacitance detection area corresponding to the mass block are both hollow areas;
the Z-axis capacitance detection area comprises the fixed structure and the movable structure surrounding the fixed structure, wherein the fixed structure and the movable structure of the first Z-axis capacitance detection area form a first Z-axis detection capacitor, and the fixed structure and the movable structure of the second Z-axis capacitance detection area form a second Z-axis detection capacitor;
when the triaxial capacitive accelerometer is applied with acceleration in the Z-axis direction, the capacity change of the first Z-axis detection capacitor and the capacity change of the second Z-axis detection capacitor are opposite.
Optionally, there is a height difference between the movable structure and the fixed structure of any Z-axis capacitance detection region.
Optionally, the mass block is correspondingly arranged as the movable structure corresponding to the first Z-axis capacitance detection area and the second Z-axis capacitance detection area;
the fixed structure and the movable structure of the first Z-axis capacitance detection area form a first Z-axis detection capacitor, and the fixed structure and the movable structure of the second Z-axis capacitance detection area form a second Z-axis detection capacitor;
when the triaxial capacitive accelerometer is applied with acceleration in the Z-axis direction, the capacity change of the first Z-axis detection capacitor and the capacity change of the second Z-axis detection capacitor are opposite.
Optionally, an elastic connection portion is disposed between the second capacitance detection portion and the third capacitance detection portion of the mass block, and the elastic connection portion is provided with at least one of the fixed anchor point and the mass block in elastic connection.
Optionally, the mass block is provided with a first elastic hollowed-out area and a second elastic hollowed-out area which are arranged along the second direction, corresponding to the elastic connecting portion;
the elastic hollowed area is provided with a fixed anchor point, the fixed anchor point is connected with the mass block through a first elastic beam extending along the second direction, and the first elastic beam of the first elastic hollowed area and the first elastic beam of the second elastic hollowed area are arranged oppositely.
Optionally, the resilient structure comprises a first and a second bullet-shaped structure arranged along the first direction, and a rigid beam located between the first and second bullet-shaped structures;
the first bullet-shaped structure comprises two second elastic beams arranged along the second direction, opposite ends of the two second elastic beams are connected with the rigid beam, and the other ends of the two second elastic beams are connected with the first mass block;
and the second bullet-shaped structure comprises two third elastic beams arranged along the second direction, opposite ends of the two third elastic beams are connected with the rigid beam, and the other ends of the two third elastic beams are connected with the second mass block.
Correspondingly, the invention also provides an electronic device which comprises the three-axis capacitive accelerometer.
Compared with the prior art, the technical scheme provided by the invention at least has the following advantages:
the invention provides a triaxial capacitive accelerometer and an electronic device, comprising: the three-axis capacitive accelerometer comprises a first mass block and a second mass block which are symmetrically arranged structurally, wherein the first mass block and the second mass block are coupled and connected through an elastic structure, and the mass blocks are movably arranged on a substrate through at least one fixed anchor point corresponding to the mass blocks and are used for generating motion corresponding to acceleration when the acceleration is applied to the three-axis capacitive accelerometer; and a plurality of detection areas located in any mass block range, wherein any detection area comprises a detection capacitor consisting of a fixed structure and a movable structure, the mass block is multiplexed with the movable structure, and the fixed structure is fixed on the substrate and used for generating specific capacitance value change with the acceleration when the triaxial capacitive accelerometer applies the acceleration. According to the technical scheme provided by the invention, the capacitance detection areas of the triaxial capacitive accelerometer share the first mass block and the second mass block, so that the number of the mass blocks is reduced, and the lightening and thinning tendency of the triaxial capacitive accelerometer is facilitated; in addition, the two coupled mass blocks are beneficial to eliminating the influence of stress generated in the process that the accelerometer is welded along with packaging or the temperature changes and the like, and the zero deviation and the sensitivity deviation of the accelerometer are effectively reduced.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, it is obvious that the drawings in the following description are only embodiments of the present invention, and for those skilled in the art, other drawings can be obtained according to the provided drawings without creative efforts.
Fig. 1 is a schematic structural diagram of a three-axis capacitive accelerometer according to an embodiment of the present disclosure;
FIG. 2 is a schematic structural diagram of a movable structure and a fixed structure of a Z-axis capacitance detection area provided in an embodiment of the present application;
fig. 3 is a schematic structural diagram of another triaxial capacitive accelerometer according to an embodiment of the present application;
FIG. 4 is a schematic structural diagram of another movable structure and a fixed structure of a Z-axis capacitance detection area provided in an embodiment of the present application;
fig. 5 is a schematic structural diagram of a three-axis capacitive accelerometer according to an embodiment of the present application, illustrating detection in the X axis;
fig. 6 is a schematic structural diagram of a three-axis capacitive accelerometer according to an embodiment of the present application, illustrating detection in the Y-axis;
fig. 7 is a schematic structural diagram of a three-axis capacitive accelerometer provided in an embodiment of the present application for detecting in a Z-axis;
fig. 8 is a schematic structural diagram of another triaxial capacitive accelerometer provided in an embodiment of the present application;
fig. 9 is a schematic structural diagram of another triaxial capacitive accelerometer according to an embodiment of the present application.
Detailed Description
The technical solutions in the embodiments of the present invention will be clearly and completely described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only a part of the embodiments of the present invention, and not all of the embodiments. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.
As described in the background art, capacitive accelerometers have become the most popular type of accelerometer due to their simple structure, low cost, and high sensitivity and linearity in low frequency range. However, the existing triaxial capacitive accelerometer generally has different mass blocks respectively arranged for different axial capacitance detection areas, and the mass blocks have large occupied area and weight, which is not favorable for the trend of lightness and thinness of the triaxial capacitive accelerometer.
Based on this, the embodiments of the present application provide a three-axis capacitive accelerometer and an electronic device, wherein the capacitance detection areas of the three-axis capacitive accelerometer share the first mass block and the second mass block, so as to reduce the number of mass blocks, which is beneficial to the trend of lightness and thinness of the three-axis capacitive accelerometer. In order to achieve the above object, the technical solutions provided by the embodiments of the present application are described in detail below, specifically with reference to fig. 1 to 9.
Referring to fig. 1, a schematic structural diagram of a three-axis capacitive accelerometer provided in an embodiment of the present application is shown, where the three-axis capacitive accelerometer includes:
the first mass block M1 and the second mass block M2 are arranged in structural symmetry, wherein the first mass block M1 and the second mass block M2 are coupled and connected through an elastic structure, and the mass blocks are movably arranged on the substrate through at least one fixed anchor point corresponding to the mass blocks and used for generating motion corresponding to acceleration when the acceleration is applied to the triaxial capacitive accelerometer;
and a plurality of detection areas located in any mass block range, wherein any detection area comprises a detection capacitor consisting of a fixed structure and a movable structure, the mass block is multiplexed with the movable structure, and the fixed structure is fixed on the substrate and used for generating specific capacitance value change with the acceleration when the triaxial capacitive accelerometer applies the acceleration.
In an embodiment of the present application, referring to fig. 1, the mass block includes a first Z-axis capacitance detection region Cz1, a second capacitance detection portion, a third capacitance detection portion, and a second Z-axis capacitance detection region Cz2 disposed along the first direction Y, wherein the second capacitance detection portion is provided with a first X-axis capacitance detection region Cx1, a first Y-axis capacitance detection region Cy1, and a second X-axis capacitance detection region Cx2 along the second direction X, and the third capacitance detection portion is provided with a third X-axis capacitance detection region Cx3, a second Y-axis capacitance detection region Cy2, and a fourth X-axis capacitance detection region Cx4 in sequence along the second direction; any detection area comprises a detection capacitor consisting of a fixed structure and a movable structure, the mass block multiplexes the movable structure, and the fixed structure is fixed on the substrate;
wherein the first direction Y is the first mass M1-second mass M2 direction, and the second direction X intersects with the first direction Y. Optionally, the first direction and the second direction are perpendicular to each other. That is, the plurality of detection regions within any one mass block range includes a first Z-axis capacitance detection region Cz1, a second Z-axis capacitance detection region Cz2, a first X-axis capacitance detection region Cx1, a first Y-axis capacitance detection region Cy1, a second X-axis capacitance detection region Cx2, a third X-axis capacitance detection region Cx3, a second Y-axis capacitance detection region Cy2, and a fourth X-axis capacitance detection region Cx 4.
It should be noted that, in an embodiment of the present application, when the first direction Y is perpendicular to the second direction X, an X axis of the three-axis capacitive accelerometer is the same as the second direction, a Y axis thereof is the same as the first direction, and a Z axis thereof is perpendicular to a plane formed by the X axis and the Y axis.
As shown in fig. 1, in an embodiment of the present application, the proof mass corresponds to the first X-axis capacitance detection region Cx1, the second X-axis capacitance detection region Cx2, the third X-axis capacitance detection region Cx3, and the fourth X-axis capacitance detection region Cx4, which are all hollow regions;
the X-axis capacitance detection area comprises a first movable structure, a first fixed structure, a second movable structure and a second fixed structure which are arranged along the first direction Y, wherein the first movable structure and the first fixed structure form a first X-axis detection capacitor 101, and the second movable structure and the second fixed structure form a second X-axis detection capacitor 102;
when acceleration in the X-axis direction is applied to the three-axis capacitive accelerometer, the capacitance changes of the first X-axis detection capacitor 101 and the second X-axis detection capacitor 102 are opposite.
As shown in fig. 1, in an embodiment of the present application, the mass block corresponds to both the first Y-axis capacitance detection area Cy1 and the second Y-axis capacitance detection area Cy2, which are hollow areas;
and the Y-axis capacitance detection area comprises a first movable structure, a first fixed structure, a second movable structure and a second fixed structure arranged along the first direction Y, wherein the first movable structure and the first fixed structure constitute a first Y-axis detection capacitor 201, and the second movable structure and the second fixed structure constitute a second Y-axis detection capacitor 202;
when acceleration in the Y-axis direction is applied to the three-axis capacitive accelerometer, the capacitance changes of the first Y-axis detection capacitor 201 and the second Y-axis detection capacitor 202 are opposite.
And, with reference to fig. 1 and fig. 2, fig. 2 is a schematic structural diagram of a movable structure and a fixed structure of a Z-axis capacitance detection area provided in an embodiment of the present application, where the mass block corresponds to both the first Z-axis capacitance detection area Cz1 and the second Z-axis capacitance detection area Cz2 which are hollow areas;
the Z-axis capacitance detection area comprises a fixed structure and a movable structure surrounding the fixed structure, wherein the fixed structure and the movable structure of the first Z-axis capacitance detection area form a first Z-axis detection capacitor 301, and the fixed structure and the movable structure of the second Z-axis capacitance detection area form a second Z-axis detection capacitor 302;
when a Z-axis acceleration is applied to the triaxial capacitive accelerometer, the capacitance changes of the first Z-axis detection capacitor 301 and the second Z-axis detection capacitor 302 are opposite.
As shown in fig. 2, the embodiment of the present application provides a height difference between the movable structure Z1 and the fixed structure Z2 of the Z-axis capacitance detection area. The specific parameters of the height difference provided in the embodiments of the present application are not limited, and it needs to be specifically designed according to practical applications, where the movable structure Z1 and the fixed structure Z2 may have a height difference at any two ends in the same direction, and the present application is not limited specifically. In an embodiment of the present application, the movable structure Z1 and the fixed structure Z2 of any Z-axis capacitance detection area have a height difference at the same direction end.
In another embodiment of the present application, the Z-axis capacitance detection area structure may also be in other structural forms. With reference to fig. 3 and 4, fig. 3 is a schematic structural diagram of another three-axis capacitive accelerometer provided in the embodiment of the present application, and fig. 4 is a schematic structural diagram of another movable structure and a fixed structure of a Z-axis capacitance detection area provided in the embodiment of the present application. Wherein the mass block is correspondingly arranged as the movable structure corresponding to the first Z-axis capacitance detection area Cz1 and the second Z-axis capacitance detection area Cz 2;
the fixed structure is fixed on the substrate and is arranged corresponding to the movable structure, wherein the fixed structure and the movable structure of the first Z-axis capacitance detection area form a first Z-axis detection capacitor 301, and the fixed structure and the movable structure of the second Z-axis capacitance detection area form a second Z-axis detection capacitor 302;
when a Z-axis acceleration is applied to the triaxial capacitive accelerometer, the capacitance changes of the first Z-axis detection capacitor 301 and the second Z-axis detection capacitor 302 are opposite.
In the sectional view along AA' direction in fig. 3 as shown in fig. 4, in the substrate-mass direction, the movable structure Z1 and the fixed structure Z2 of the Z-axis capacitance detection area are overlapped, and a gap is provided between the movable structure Z1 and the fixed structure Z2 to form a Z-axis detection capacitance.
It should be noted that, the specific manners of the movable structure and the fixed structure of the Z-axis capacitance detection area are only two of the structures in the present application, and the movable structure and the fixed structure of the Z-axis capacitance detection area may also be formed into the detection capacitor in other manners in other embodiments of the present application, and the present application is not limited specifically.
As shown in fig. 1, in an embodiment of the present application, an elastic connection portion is disposed between the second capacitive detection portion and the third capacitive detection portion of the mass, and the elastic connection portion is provided with at least one of the anchor points and is elastically connected to the mass.
The mass block is provided with a first elastic hollow area 410 and a second elastic hollow area 420 which are arranged along the second direction X corresponding to the elastic connecting part;
the elastic hollow area is provided with one of the fixed anchors 400, and the fixed anchor 400 is connected to the mass block through a first elastic beam 430 extending along the second direction X, wherein the first elastic beam 430 of the first elastic hollow area 410 and the first elastic beam 430 of the second elastic hollow area 420 are disposed opposite to each other. The triaxial capacitive accelerometer provided by the embodiment of the application realizes the purpose that two mass blocks commonly detect three accelerations in different axial directions by using a mode that a fixed anchor point is not located at the center position of the fixed anchor point. And each mass block is fixed by two fixed anchor points, so that the asymmetry caused by process deviation is reduced, and the reliability and the stability of the triaxial capacitive accelerometer are improved.
And, as shown in fig. 1, the elastic structure comprises a first bullet-shaped structure and a second bullet-shaped structure arranged along the first direction Y, and a rigid beam 600 located between the first bullet-shaped structure and the second bullet-shaped structure;
the first bullet-shaped structure comprises two second elastic beams 510 arranged along the second direction X, opposite ends of the two second elastic beams 510 are connected with the rigid beam 600, and the other ends of the two second elastic beams 510 are connected with the first mass M1;
and, the second bullet-shaped structure includes two third elastic beams 520 arranged along the second direction X, opposite ends of the two third elastic beams 520 are connected to the rigid beam 600, and the other ends of the two third elastic beams 520 are connected to the second mass M2. The two mass blocks are connected by the elastic beam coupling structure, so that the displacement width of the two mass blocks is limited, and the problem of adhesion or fracture caused by overlarge displacement is avoided. In addition, according to the technical scheme provided by the embodiment of the application, the two mass blocks are respectively subjected to differential detection of the capacitance, so that the influence of the stress caused by the processes of process deviation, packaging, welding or environmental temperature change and the like on a single mass block is reduced.
The detection process of the three-axis capacitive accelerometer provided in the embodiment of the present application is described in detail below with reference to schematic diagrams shown in fig. 5 to 7.
Referring to fig. 5, a schematic structural diagram of the three-axis capacitive accelerometer provided in this embodiment of the application for detecting in the X axis is shown, where when the three-axis capacitive accelerometer has an acceleration in the X axis, due to an uneven structural mass formed by the first mass M1 and the second mass M2, a position motion displacement of the first mass M1 and the second mass M2 close to the rigid beam 600 may be greater than a position motion displacement of positions away from both sides of the rigid beam 600. Taking the direction identified in fig. 3 as an example, the capacitances of the first X detection capacitance 101 of the first X-axis capacitance detection region Cx1 and the third X-axis capacitance detection region Cx3, and the second X detection capacitance 102 of the second X-axis capacitance detection region Cx2 and the fourth X-axis capacitance detection region Cx4 are reduced; and the capacitance of the second X-axis detection capacitance 102 of the first X-axis capacitance detection region Cx1 and the third X-axis capacitance detection region Cx3, and the capacitance of the first X-axis detection capacitance 101 of the second X-axis capacitance detection region Cx2 and the fourth X-axis capacitance detection region Cx4, which are opposite thereto, are increased. The subsequent detection circuit can measure the acceleration of the triaxial capacitive accelerometer in the X-axis direction through the differential capacitance change of the eight capacitance-reduced X-axis detection capacitors and the eight capacitance-increased X-axis detection capacitors in total in the first mass M1 and the second mass M2.
Referring to fig. 6, a schematic structural diagram of the three-axis capacitive accelerometer provided in the embodiment of the present application for detecting in the Y-axis is shown, where when the three-axis capacitive accelerometer has acceleration in the Y-axis, the first mass M1 and the second mass M2 move toward the Y-axis direction. Taking the direction indicated in fig. 4 as an example, the capacitance of the first Y-axis capacitance detection area Cy1 and the first Y-axis detection capacitance 201 of the second Y-axis capacitance detection area Cy2 is thereby reduced; and the capacitance of the second Y-axis detection capacitor 202 of the first and second Y-axis capacitance detection areas Cy1 and Cy2, which are opposite thereto, is increased. The subsequent detection circuit can measure the acceleration of the three-axis capacitive accelerometer in the Y-axis direction through the differential capacitance change of the four reduced-capacitance Y-axis detection capacitors and the four increased-capacitance Y-axis detection capacitors in the first mass M1 and the second mass M2.
And referring to fig. 7, a schematic structural diagram of the triaxial capacitive accelerometer provided in the embodiment of the present application for detecting in the Z axis is shown, where when the triaxial capacitive accelerometer has an acceleration in the Z axis, due to an uneven structural mass formed by the first mass M1 and the second mass M2, a displacement of a position motion of the first mass M1 and the second mass M2 close to the rigid beam 600 is greater than a displacement of a position motion of positions of the two masses M2 away from two sides of the rigid beam 600. Taking the orientation of fig. 5 as an example, the capacitance of the first Z-axis detection capacitor 301 of the first Z-axis capacitance detection region Cz1 is thereby decreased; and the capacitance of the second Z-axis detection capacitor 302 of the opposite second Z-axis capacitance detection region is increased. The subsequent detection circuit can measure the acceleration of the triaxial capacitive accelerometer in the Z-axis direction through the differential capacitance change of the two capacitance-reduced first Z-axis detection capacitors 301 and the two capacitance-increased second Z-axis detection capacitors 302 in the first mass M1 and the second mass M2.
In any of the above embodiments of the present application, the fixed structure is a fixed electrode plate, the movable structure is a movable electrode plate, wherein any detection area includes the fixed electrode plate and a detection capacitor formed by the movable electrode plate, and the mass block multiplexes the movable electrode plate, and the fixed electrode plate is fixed on the substrate.
The triaxial capacitive accelerometer comprises a first mass block and a second mass block which are arranged in a coupling connection mode, wherein the first mass block and the second mass block in the coupling connection mode have a correlation in movement in a certain dimension. Specifically, when the first mass block and the second mass block provided in the embodiment of the present application are subjected to acceleration in a certain direction, if the first mass block rotates clockwise, the second mass block rotates counterclockwise, and the coupling connection can ensure that the rotation angles of the first mass block and the second mass block are consistent.
In the three-axis capacitive accelerometer provided by the present application, the purpose of detecting the acceleration in the X-axis, Y-axis and Z-axis directions can be achieved by the X-axis capacitance detection area, the Y-axis capacitance detection area and the Z-axis capacitance detection area, respectively, wherein, in the three-axis capacitive accelerometer provided by the present application, not limited to the limitations regarding the number and positions of the X-axis capacitance detection area, the Y-axis capacitance detection area and the Z-axis capacitance detection area provided by the above-mentioned embodiments shown in fig. 1 to 5, the number of the X-axis capacitance detection area, the Y-axis capacitance detection area and the Z-axis capacitance detection area can be increased or decreased on the basis of the number provided by the above-mentioned embodiments, and the positions of the X-axis capacitance detection area, the Y-axis capacitance detection area and the Z-axis capacitance detection area can also be changed on the basis of the positions provided by the above-mentioned embodiments, as long as triaxial capacitive accelerometer guarantees first quality piece and second quality piece coupling connection, and can realize the detection purpose of the acceleration of X axle, Y axle and Z axle direction can, promptly, on first quality piece and second quality piece coupling connection, and can realize the basis of the detection of the acceleration of X axle, Y axle and Z axle direction, all belong to the scheme that this application protected to the deformation of quantity and position that X axle electric capacity detection area, Y axle electric capacity detection area and Z axle electric capacity detection area go on.
The structures of two other three-axis capacitive accelerometers provided by the present application are described with reference to fig. 8 and 9.
Referring to fig. 8, a schematic structural diagram of another three-axis capacitive accelerometer provided in an embodiment of the present application is shown, wherein a Y-axis capacitance detection area and a Z-axis capacitance detection area of the three-axis capacitive accelerometer shown in fig. 8 are the same as those shown in fig. 1, that is, the first mass M1 and the second mass M2 include a first Y-axis capacitance detection area Cy1 and a second Y-axis capacitance detection area Cy2, and include a first Z-axis capacitance detection area Cz1 and a second Z-axis capacitance detection area Cz 2.
Unlike in fig. 1, in the three-axis capacitive accelerometer of fig. 8 of the present application, both the number and the location of the X-axis capacitance sensing areas are varied, that is, each of the first mass M1 and the second mass M2 includes only two X-axis capacitive sensing regions, a first X-axis capacitive sensing region Cx1 and a second X-axis capacitive sensing region Cx2, and the first X-axis capacitance detection region Cx1 and the second X-axis capacitance detection region Cx2 are respectively provided on opposite sides of the proof mass in the second direction X, and the first X-axis capacitance detection region Cx1 and the second X-axis capacitance detection region Cx2 extend in the same direction as the first direction Y, the movable structure and the fixed structure are arranged opposite to each other in the second direction X, so as to ensure that, in the presence of an acceleration on the X axis, capacitance between the movable structure and the fixed structure extending in the first direction Y changes, and acceleration is detected based on the change in capacitance.
And, referring to fig. 9, a schematic structural diagram of another three-axis capacitive accelerometer provided in the embodiment of the present application is shown, wherein a Z-axis capacitance detection region of the three-axis capacitive accelerometer shown in fig. 8 is the same as the structure shown in fig. 1, that is, the first mass M1 and the second mass M2 include a first Z-axis capacitance detection region Cz1 and a second Z-axis capacitance detection region Cz 2.
Unlike in fig. 1, in the three-axis capacitive accelerometer of fig. 9 of the present application, the position of the X-axis capacitance detection region is changed, that is, each of the first mass M1 and the second mass M2 includes a first X-axis capacitance detection region Cx1, a second X-axis capacitance detection region Cx2, a third X-axis capacitance detection region Cx3, and a fourth X-axis capacitance detection region Cx4, wherein each of the first X-axis capacitance detection region Cx1, the second X-axis capacitance detection region Cx2, the third X-axis capacitance detection region Cx3, and the fourth X-axis capacitance detection region Cx4 is disposed in an inclined manner toward the central region of the mass.
And, unlike the other point in fig. 1, in the three-axis capacitive accelerometer of the present application shown in fig. 9, the number and the positions of the Y-axis capacitance detection areas are changed, that is, each of the first mass M1 and the second mass M2 includes a first Y-axis capacitance detection area Cy1, a second Y-axis capacitance detection area Cy2, a third Y-axis capacitance detection area Cy3, and a fourth Y-axis capacitance detection area Cy 4. The first Y-axis capacitance detection area Cy1 and the second Y-axis capacitance detection area Cy2 are sequentially arranged along the second direction X, the third Y-axis capacitance detection area Cy3 and the fourth Y-axis capacitance detection area Cy4 are sequentially arranged along the second direction X, and a combination of the first Y-axis capacitance detection area Cy1 and the second Y-axis capacitance detection area Cy2 and a combination of the third Y-axis capacitance detection area Cy3 and the fourth Y-axis capacitance detection area Cy4 are arranged on two sides of the elastic hollow area along the first direction Y and between the first Z-axis capacitance detection area Cz1 and the second Z-axis capacitance detection area Cz 2.
Correspondingly, an embodiment of the present application further provides an electronic device, including the three-axis capacitive accelerometer provided in any of the above embodiments.
The embodiment of the application provides a triaxial capacitive accelerometer and electronic device, includes: the three-axis capacitive accelerometer comprises a first mass block and a second mass block which are symmetrically arranged structurally, wherein the first mass block and the second mass block are coupled and connected through an elastic structure, and the mass blocks are movably arranged on a substrate through at least one fixed anchor point corresponding to the mass blocks and are used for generating motion corresponding to acceleration when the acceleration is applied to the three-axis capacitive accelerometer; and a plurality of detection areas located in any mass block range, wherein any detection area comprises a detection capacitor consisting of a fixed structure and a movable structure, the mass block is multiplexed with the movable structure, and the fixed structure is fixed on the substrate and used for generating specific capacitance value change with the acceleration when the triaxial capacitive accelerometer applies the acceleration. According to the technical scheme provided by the invention, the capacitance detection areas of the triaxial capacitive accelerometer share the first mass block and the second mass block, so that the number of the mass blocks is reduced, and the lightening and thinning tendency of the triaxial capacitive accelerometer is facilitated; in addition, the two coupled mass blocks are beneficial to eliminating the influence of stress generated in the process that the accelerometer is welded along with packaging or the temperature changes and the like, and the zero deviation and the sensitivity deviation of the accelerometer are effectively reduced.
The previous description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the present invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles defined herein may be applied to other embodiments without departing from the spirit or scope of the invention. Thus, the present invention is not intended to be limited to the embodiments shown herein but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.
Claims (7)
1. A three-axis capacitive accelerometer, comprising:
the three-axis capacitive accelerometer comprises a first mass block and a second mass block which are symmetrically arranged structurally, wherein the first mass block and the second mass block are coupled and connected through an elastic structure, and the mass blocks are movably arranged on a substrate through at least one fixed anchor point corresponding to the mass blocks and are used for generating motion corresponding to acceleration when the acceleration is applied to the three-axis capacitive accelerometer;
the mass block is used for multiplexing the movable structure, and the fixed structure is fixed on the substrate and used for generating specific capacitance value change corresponding to acceleration when the acceleration is applied to the three-axis capacitive accelerometer; and is
The mass block comprises a first Z-axis capacitance detection area, a second capacitance detection part, a third capacitance detection part and a second Z-axis capacitance detection area which are arranged along a first direction, wherein the second capacitance detection part is provided with a first X-axis capacitance detection area, a first Y-axis capacitance detection area and a second X-axis capacitance detection area along a second direction, and the third capacitance detection part is sequentially provided with a third X-axis capacitance detection area, a second Y-axis capacitance detection area and a fourth X-axis capacitance detection area along the second direction; wherein the first direction is the first mass-second mass direction, and the second direction intersects the first direction;
an elastic connecting part is arranged between the second capacitance detection part and the third capacitance detection part of the mass block; the mass block is provided with a first elastic hollowed-out area and a second elastic hollowed-out area which are arranged along the second direction corresponding to the elastic connecting part; the fixed anchor point is arranged in the elastic hollowed-out area and is connected with the mass block through a first elastic beam extending along the second direction, wherein the first elastic beams of the first elastic hollowed-out area and the second elastic hollowed-out area are arranged oppositely;
the elastic structure comprises a first bullet-shaped structure and a second bullet-shaped structure which are arranged along the first direction, and a rigid beam positioned between the first bullet-shaped structure and the second bullet-shaped structure; the first bullet-shaped structure comprises two second elastic beams arranged along the second direction, opposite ends of the two second elastic beams are connected with the rigid beam, and the other ends of the two second elastic beams are connected with the first mass block; the second bullet-shaped structure comprises two third elastic beams arranged along the second direction, opposite ends of the two third elastic beams are connected with the rigid beam, and the other ends of the two third elastic beams are connected with the second mass block.
2. The three-axis capacitive accelerometer of claim 1, wherein the mass corresponding to the first, second, third, and fourth X-axis capacitance detection regions are all hollowed-out regions;
the X-axis capacitance detection area comprises a first movable structure, a first fixed structure, a second movable structure and a second fixed structure which are arranged along the first direction, wherein the first movable structure and the first fixed structure form a first X-axis detection capacitor, and the second movable structure and the second fixed structure form a second X-axis detection capacitor;
when acceleration in the X axial direction is applied to the three-axis capacitive accelerometer, the capacity change of the first X-axis detection capacitor and the capacity change of the second X-axis detection capacitor are opposite.
3. The three-axis capacitive accelerometer of claim 1, wherein the mass corresponding to the first and second Y-axis capacitive sensing areas are both hollowed-out areas;
the Y-axis capacitance detection area comprises a first movable structure, a first fixed structure, a second movable structure and a second fixed structure which are arranged along the first direction, wherein the first movable structure and the first fixed structure form a first Y-axis detection capacitor, and the second movable structure and the second fixed structure form a second Y-axis detection capacitor;
when acceleration in the Y-axis direction is applied to the three-axis capacitive accelerometer, the capacity change of the first Y-axis detection capacitor and the capacity change of the second Y-axis detection capacitor are opposite.
4. The three-axis capacitive accelerometer of claim 1, wherein the proof mass corresponding to the first and second Z-axis capacitive detection areas are both hollowed-out areas;
the Z-axis capacitance detection area comprises the fixed structure and the movable structure surrounding the fixed structure, wherein the fixed structure and the movable structure of the first Z-axis capacitance detection area form a first Z-axis detection capacitor, and the fixed structure and the movable structure of the second Z-axis capacitance detection area form a second Z-axis detection capacitor;
when the triaxial capacitive accelerometer is applied with acceleration in the Z-axis direction, the capacity change of the first Z-axis detection capacitor and the capacity change of the second Z-axis detection capacitor are opposite.
5. The three-axis capacitive accelerometer of claim 4, wherein there is a height difference between the moveable and fixed structures of any Z-axis capacitive sensing area.
6. The three-axis capacitive accelerometer of claim 1, wherein the areas of the mass corresponding to the first and second Z-axis capacitive sensing areas are disposed correspondingly as the moveable structure;
the fixed structure and the movable structure are fixed on the substrate and are arranged corresponding to the movable structure, wherein the fixed structure and the movable structure of the first Z-axis capacitance detection area form a first Z-axis detection capacitor, and the fixed structure and the movable structure of the second Z-axis capacitance detection area form a second Z-axis detection capacitor;
when the triaxial capacitive accelerometer is applied with acceleration in the Z-axis direction, the capacity change of the first Z-axis detection capacitor and the capacity change of the second Z-axis detection capacitor are opposite.
7. An electronic device comprising a three-axis capacitive accelerometer according to any of claims 1 to 6.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710333977.9A CN107037237B (en) | 2017-05-12 | 2017-05-12 | Triaxial capacitive accelerometer and electronic device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710333977.9A CN107037237B (en) | 2017-05-12 | 2017-05-12 | Triaxial capacitive accelerometer and electronic device |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN107037237A CN107037237A (en) | 2017-08-11 |
| CN107037237B true CN107037237B (en) | 2022-06-24 |
Family
ID=59537178
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710333977.9A Active CN107037237B (en) | 2017-05-12 | 2017-05-12 | Triaxial capacitive accelerometer and electronic device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN107037237B (en) |
Families Citing this family (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110308308B (en) * | 2019-06-27 | 2021-07-13 | 深迪半导体(绍兴)有限公司 | In-plane translational accelerometer with compensation electrode |
| CN111208317B (en) | 2020-02-26 | 2021-07-02 | 深迪半导体(绍兴)有限公司 | MEMS inertial sensor, application method and electronic equipment |
| CN114720721B (en) * | 2022-03-17 | 2024-04-26 | 苏州敏芯微电子技术股份有限公司 | Capacitive acceleration sensor |
Family Cites Families (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| RU2251702C1 (en) * | 2004-07-02 | 2005-05-10 | Государственное образовательное учреждение высшего профессионального образования "Московский государственный институт электронной техники (технический университет)" (МИЭТ) | Micromechanical accelerometer |
| CN101852816B (en) * | 2009-12-31 | 2012-07-18 | 中国电子科技集团公司第四十九研究所 | Piezoresistive monolithic integrated tri-axial acceleration sensor and manufacturing method thereof |
| GB201322918D0 (en) * | 2013-12-23 | 2014-02-12 | Atlantic Inertial Systems Ltd | Accelerometers |
| CN204255978U (en) * | 2014-11-25 | 2015-04-08 | 东南大学 | A kind of split type difference silicon micro-resonance type accelerometer |
| CN204314330U (en) * | 2014-12-25 | 2015-05-06 | 歌尔声学股份有限公司 | Z axis structure in a kind of accelerometer and three axis accelerometer |
| CN104931729B (en) * | 2015-06-29 | 2017-12-05 | 歌尔股份有限公司 | A kind of MEMS triaxial accelerometer |
| CN105606845A (en) * | 2015-12-23 | 2016-05-25 | 北京航空航天大学 | Dual-mass-block high sensitivity silicon micro resonant accelerometer structure based on two-level micro-levers |
-
2017
- 2017-05-12 CN CN201710333977.9A patent/CN107037237B/en active Active
Also Published As
| Publication number | Publication date |
|---|---|
| CN107037237A (en) | 2017-08-11 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108020687B (en) | MEMS accelerometer | |
| US8205498B2 (en) | Multi-axis capacitive accelerometer | |
| US7210351B2 (en) | Micro accelerometer | |
| US8459114B2 (en) | Multi-axis capacitive accelerometer | |
| CN106370889B (en) | Multi-axis inertial sensor with dual mass blocks and integrated damping structure | |
| US7814794B2 (en) | Micromachined sensors | |
| CN107271722B (en) | Triaxial capacitive accelerometer | |
| JP3327595B2 (en) | 3-axis accelerometer | |
| US8333113B2 (en) | Triaxial acceleration sensor | |
| JP6303074B2 (en) | Inertial measurement module and 3-axis accelerometer | |
| JP5553846B2 (en) | Acceleration sensor and method of operating acceleration sensor | |
| CN107037237B (en) | Triaxial capacitive accelerometer and electronic device | |
| US8413511B2 (en) | Accelerometer | |
| WO2015033543A1 (en) | Acceleration sensor | |
| JP5799929B2 (en) | Acceleration sensor | |
| CN102128953A (en) | Capacitive micro-acceleration sensor with symmetrically inclined folded beam structure | |
| TW202016548A (en) | Increased sensitivity z-axis accelerometer | |
| CN113624991A (en) | Z-axis accelerometer | |
| CN110366685B (en) | Electrode layer partitioning | |
| CN107782914B (en) | Three-axis accelerometer | |
| CN107782913B (en) | Triaxial capacitive accelerometer | |
| JP6070113B2 (en) | Acceleration sensor | |
| CN216595182U (en) | Z-axis accelerometer | |
| CN107782916B (en) | Three-axis accelerometer | |
| CN115078769B (en) | MEMS accelerometer |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| CB02 | Change of applicant information | ||
| CB02 | Change of applicant information |
Address after: 312030 Building 5, intelligent innovation center, 487 Kebei Avenue, Keqiao Economic and Technological Development Zone, Keqiao District, Shaoxing City, Zhejiang Province Applicant after: Shendi semiconductor (Shaoxing) Co.,Ltd. Address before: Room 306, building a, building 1, 3000 Longdong Avenue, Shanghai pilot Free Trade Zone, 201203 Applicant before: SENODIA TECHNOLOGIES (SHANGHAI) Co.,Ltd. |
|
| GR01 | Patent grant | ||
| GR01 | Patent grant |