CN206772316U - Mems gyroscope and its electronic system - Google Patents

Abstract

Disclosure MEMS gyroscope and its electronic system.Specially a kind of MEMS gyroscope (60,100), wherein, suspended mass (111 114) is removable relative to supporting construction (125,127).The removable mass is influenceed by quadrature error caused by orthogonal torque；Driving structure (77) is coupled to the suspended mass to control the removable movement of mass in the driven direction with driving frequency.The movement of the removable mass on sensing direction is detected coupled to the motion sensing electrode (130) that may move mass, and quadrature compensation electrode (121 124) may move mass to generate the compensating torque opposite with the orthogonal torque coupled to this.The gyroscope is configured for being biased these quadrature compensation electrodes using offset voltage, so that the resonant frequency of the removable mass and the difference of the driving frequency have predeterminated frequency mismatch value.

Description

MEMS gyroscope and its electronic system

Technical field

It the utility model is related to a kind of MEMS gyroscope and its electronic system.

Background technology

As it is known, MEMS (Microelectromechanical System, MEMS) by its small size, With consumer various applications are increasingly being used for using compatible cost and increased reliability.Specifically, form as The inertial sensors such as micro- integrated gyroscope and electromechanical oscillator using this technology.

Such MEMS device generally include supporter and by spring or " bending section " and be suspended on supporter it Go up and be coupled at least one removable mass of supporter.Spring is arranged to enable removable mass according to one Individual or multiple frees degree are relative to support oscillation body.The capacitively coupled multiple fixed electricity on supporter of removable mass Pole, so as to form the capacitor with variable capacitance.When MEMS device is operated as sensor, mass may move The electric capacity of capacitor is changed due to the effect for the power being applied to it relative to the movement of the fixed electrode on supporter.It is this Change allows to detect displacement of the removable mass relative to supporter, and according to the latter, can detect and cause displacement External force.On the contrary, when MEMS device is operated as actuator, such as pass through single one group of actuating or driving electrodes Apply appropriate bias voltage to removable mass, so that removable mass, which is subjected to causing, it is expected mobile electrostatic Power.

Among MEMS sensor, specifically, gyroscope has complicated electromechanical structure, and the structure is generally included relative to branch Moveable at least two mass of support body, at least two mass are coupled to each other so that with multiple frees degree, (this depends on In the framework of system).In most cases, each removable mass has one or most two frees degree.It is removable Mass is by fixed sensing electrode and removable sensing electrode and by activation electrodes or driving electrodes and capacitively coupled To supporter.

In the embodiment with two removable masses, the first removable mass be exclusively used in driving and with by Amplitude of oscillation is controlled to keep vibrating with resonant frequency.Second removable mass passes through the with (translation or rotation) oscillating movement One removable mass drives, and when micro-structural rotate around the axle of gyroscope with a fixed angular speed, and this second may move Mass is subjected to Coriolis force (Coriolis Force) proportional to angular speed itself and perpendicular to driving direction. In practice, the second (powered) removable mass serves as accelerometer, and the accelerometer makes it possible to detect Ke Liao Sharp power and detection angular speed.

In another embodiment, single suspended mass is coupled to supporter so as to only according to two relative to supporter The vertical free degree (that is, driving the free degree and the sensing free degree) is removable.The sensing free degree can be enabled to along removable kinoplaszm The planar movement (being moved in plane) of gauge block or perpendicular to the planar movement (flat out-of-plane movement).Actuating or driving equipment make to hang Hang mass and keep controlled oscillation according to one of the two frees degree.Suspended mass in response to supporter rotation (due to section Li Aolili) moved based on another free degree.

However, MEMS gyroscope has labyrinth, and for example frequently occurred due to production defect and process spread Non-ideal electromechanical interaction between suspended mass and supporter.Therefore, useful signal component mixes with parasitic component, posts The measurement of amount angular velocity estranged is not contributed and is potential noise source, and the influence of these noise sources is unpredictalbe.

For example, suspended mass and support body between elastic connection the shortcomings that may cause suspended mass not Vibration with the desired free degree in the design phase on completely the same direction.This defect is also possible to cause with fast along angle The beginning of the power of the component of the detection free degree orientation of degree.This power and then generate with unknown amplitude, frequency and carrier wave Frequency identical and the component of signal with 90 ° of phase shifts for causing the error for being referred to as " quadrature error ".

Can be from non-ideal gyroscope 1 ' (Figure 1B) representing preferable gyroscope 1 (Figure 1A) respectively and being subjected to quadrature error Movement Figure 1A and Figure 1B comparison in understand this influence, wherein, it is schematic only about part discussed below Ground illustrates gyroscope 1,1 '.

Gyroscope 1 and 1 ' have sensing mass 5, the sensing mass in a first direction (driving direction A, herein with flute The axle X of karr referential is parallel) on by by fixed electrode 7 (being connected with substrate stiffness, be not shown) and travelling electrode 8 (with Sensing mass 5 be rigidly connected) represent driver element 6 drive.By fixed electrode 11 (being connected with substrate stiffness, be not shown) and Coriolis force is detected in second direction by the sensing unit 10 represented with the sensing rigidly connected travelling electrode 12 of mass 5 Caused movement on (sensing direction B, herein parallel to the axle Z of cartesian reference system).

In preferable gyroscope 1, rightly driving senses mass 5 on driving direction A.On the contrary, in non-ideal gyro In instrument 1 ', driving sensing mass 5, the horizontal direction have the drive components along sensing direction B on horizontal direction W.

Parasitism on sensing direction B is mobile to be caused the movement influenceed by quadrature error to sensing mass 5 Detection.

In order to compensate quadrature error, in known gyroscope, it is possible to acted in each point of sensing chain.

Specifically, the solution of both the high stability of gyroscope with high-temperature stability and over time is enable It is so-called static elimination method, including the electrode under each suspended mass is provided.

For example, Fig. 2 shows the gyroscope 10 with suspended structure in a simplified manner, herein, the suspended structure forms four Individual sensing mass 11,12,13 and 14.Herein, sensing mass 11 to 14 has general quadrangle form (for example, rectangle), And relative to gyroscope 10 center C and symmetrically pacified in couples parallel to plotting planes (plane XZ) under static state Row.Specifically, respectively with quality m₁And m₂The first sensing mass 11 and second sense mass 12 along the first drive shaft D1 (herein, parallel to axle X) is driven, and relative to the second drive shaft D2 vertical and parallel with axle Y with the first drive shaft D1 (the 3rd sensing mass 13 and the 4th senses the drive shaft of mass 14) is arranged symmetrically to each other.As mentioned, the 3rd Sensing mass 13 and the 4th senses mass 14 and arranged symmetrically to each other relative to the first drive shaft D1, and is driven along second Moving axis D2 is driven.Hereinafter, this specification will relate to only first pair of sensing mass 11,12, but herein below is also fitted For second pair of mass 13,14, hence it is evident that consider respective drive and sensitive axis.

Sensing mass 11,12 is anchored into substrate (not shown) by multiple elastomeric springs or spring, wherein, the figure is only Show the spring 16 being arranged between sensing mass 11 to 14 and the centroplasm gauge block 15 that substrate is hinged at the C of center In order to around it is unshowned parallel with axle X, Y and extend through center C axle rotation.Spring 16 to sensing mass 11,12 Two frees degree are provided and more specifically allow for the translational motion along the first drive shaft D1 and sensing movement, should Sensing movement has component on the vertical direction D3 parallel with axle Z.

Each sensing mass 11,12 has opening 17,18 respectively in center of mass.In Fig. 3 schematic side elevation The two pairs of compensating electrodes 20,21 and 22,23 shown are arranged under each opening 17,18 respectively.Fig. 3 also show substrate 25, should Substrate extends under the plane of Fig. 2 suspended structure, is schematically shown herein by its mechanical equivalent.Specifically, herein, it is used for The spring 16 for being connected to centroplasm gauge block 15 is schematically illustrated as hinge, and as further spring 26, these are further The opposite end of sensing mass 11,12 of the spring arrangement in Fig. 3 expression and removable mass 11,12 is connected to Fixed structure 27 generally rigidly connected with substrate 25.Compensating electrode is arranged in what is be represented by dotted lines respectively to 20,21 and 22,23 Near corresponding opening 17,18, so that each half of compensating electrode 20 to 23 senses mass 11,12 times extensions simultaneously corresponding And half is in corresponding opening 17,18 times extensions.

In the case where quadrature error be present, the non-ideal direction outside the plane (Fig. 2 plane XZ) of gyroscope 10 M_D1、M_D2Driving sensing mass 11,12 on (Fig. 3).Specifically, non-ideal direction M_D1、M_D2May have along parallel with axle Z The component of vertical sensing measurement axle (being indicated herein by D3).Then, Fig. 2,3 gyroscope 10 can suffer from normal force F_Q(these are orthogonal Power is assumed to be with the normal forces for two sensing masses 11,12 identical and is shown here as being applied to and is coupled to The end of the sensing mass 11,12 of heart mass 15), so as to cause sensing mass 11,12 to be rotated on sensing direction D3 Mobile (being not shown, but referring to Fig. 6 A).

Electrostatic quadrature error cancelling method include to compensating electrode 20 to 23 apply corresponding to once-through type offset voltage V1, V2、V3、V4.Specifically, the offset voltage V1 to V4 applied generally has values below：

V1=V3=VCM- Δs V

V2=V4=VCM+ Δs V

Wherein, for each gyroscope 10, VCM and Δ V are determined in calibration phase.With rotor voltage V_RFurther biasing sense Mass metering block 11,12.

In practice, compensating electrode 20 to 24 generates balancing force F_C(it is here indicated as relative to electrode 20 to 23 Centre position applies), it is intended to mechanically balance normal force F_Q, eliminate caused by quadrature error and on sensing direction D3 It is mobile.

However, this not fully solves problem.In fact, asymmetry of the compensating electrode 20 to 24 due to gyroscope arrangement With it is unbalance and increase scope of activities.Further, apply auxiliary voltage and add electrostatic softening effect, i.e. due to may move zero Gyroscope elastic constant caused by existing electrical potential difference changes and the resonance of these caused equipment between part and retaining element Frequency changes.For example, in the case of electrostatic Compensation discussed above, electrostatic softening effect may need resonant frequency f₀(from 22kHz to 18kHz) sense change.This change is commonly known as " frequency mismatch ".

On the other hand, the presence of high-frequency mismatch determines the significant changes of the sensitivity of gyroscope and its drop of performance Level.

In order to overcome due to electrostatic softening and caused frequency mismatch problem, it is possible to be introduced into synchronizing frequency tuning electricity Pole, one frequency tuning electrode of each sensitive axis of gyroscope.

According to this mode, there are gyroscope 15 electrodes (to be used for what quadrature error compensated for each sensitive axis Four electrodes add three electrodes for being used for frequency mismatch compensation).Then, as shown in Figure 4, it would be desirable at least nine Driver 30,31 and at least six DAC 32,33.

In fact, make in this way, by six drive circuits 30 and three DAC32, according to provided hereinafter Equation [1], drive (should be noted in a differential manner by the quadrature error elimination electrode of Q1X, Q2X, Q1Y, Q2Y, Q1Z, Q2Z sign Meaning, Fig. 4 illustrate only one of two electrode groups under identical voltage).For constant common-mode as shown in Figure 5A electricity VCM is pressed, the Δ Vx of differential voltage 2,2 Δ Vy, the 2 Δ Vz applied to each pair electrode are optimized for generation and eliminates quadrature error Q_γThe orthogonal Q of compensation_el.Specifically, Fig. 5 A are shown：Using this solution, offset voltage V1, V2 applied is linearly Depending on the orthogonal Q of the compensation to be generated_el。

On the contrary, Fig. 5 B show by discussed above softened according to the VT VQ applied electrostatic and produced Resonant frequency f₀Change.As shown in Figure 4, VT VQ can be applied using three single-ended DAC 33.

This mode will cause presence due to further electrode Q3x, Q3y, Q3z and the increase of caused equipment size and Respective drive circuit (DAC 33 and buffer 31) size is caused to increase.

Utility model content

The purpose of this utility model is to provide solution the shortcomings that can overcoming prior art.

According to the utility model, as limited in the dependent claims, there is provided a kind of MEMS gyroscope, one kind For the method for controlling MEMS gyroscope and a kind of method for being used to set the compensating parameter of MEMS gyroscope.

Specifically, there is provided a kind of MEMS gyroscope (60,100), including：Supporting construction (125,127)；Mass (111-114), the mass are tied on driving direction (D1) perpendicular to one another and sensing direction (D3) relative to the support Structure be may move, and the removable mass is influenceed by quadrature error caused by orthogonal torque；Driving structure (77), the driving Structure Coupling is to the removable mass to control the removable mass on the driving direction with driving frequency Movement；Motion sensing electrode (130), the motion sensing electrode are coupled to the removable mass, described to detect Movement of the removable mass on the sensing direction；And quadrature compensation electrode (121-124), the quadrature compensation electrode Coupled to the removable mass, to generate the compensating torque opposite with the orthogonal torque；The removable mass With variable resonant frequency, the difference of the resonant frequency and the driving frequency is frequency mismatch；The gyroscope is configured to For being biased using offset voltage to the quadrature compensation electrode, so as to described removable to drive with predeterminated frequency mismatch Kinoplaszm gauge block.

According to one embodiment, offset voltage can with the quadrature error it is secondary change.

According to one embodiment, quadrature compensation electrode (121-124) includes the first quadrature compensation electrode and the second orthocomplement, orthogonal complement Electrode is repaid, the first quadrature compensation electrode and the second quadrature compensation electrode are configured for respectively with the first compensation electricity Press V₁With the second offset voltage V₂And biased, wherein, V₁And V₂It is selected for meeting equation：

Wherein：Δf₀It is the predeterminated frequency mismatch；V_RIt is the bias voltage of the removable mass (111-114)； ω_S0It is the resonant frequency of the removable mass；Ks/J is the parameter related to the mechanical constant of the removable mass； And f_dIt is the driving frequency.

According to one embodiment, the first offset voltage V₁With the second offset voltage V₂Meet equation：

Q_el+Q_γ=0

Wherein：Q_elIt is that the compensation provided by below equation is orthogonal：

Q_el=k_Q[(V_R-V₁)²-(V_R-V₂)²],

Q_γIt is the quadrature error, k_qIt is by the orthogonal Q of compensation_elWith the compensating torque M_elThe ratio connected is normal Number.

It is configured for according to one embodiment, including memory component (91), the memory component described in storage The value of offset voltage.

Additionally provide a kind of electronic system, including control unit (410) and above-mentioned MEMS gyroscope (60), the MEMS Gyroscope is coupled to described control unit (410).

In practice, this gyroscope is configured so that identical quadrature error compensating electrode acts to also control frequency Mismatch.As discussed hereinafter in detail, this comes to quadrature error by using with voltage that frequency mismatch has parabolic relation Compensating electrode is biased and obtained.

Brief description of the drawings

In order to more fully understand the utility model, now only by way of non-limiting example, describe this with reference to the accompanying drawings The preferred embodiment of utility model, in the accompanying drawings：

- Figure 1A and Figure 1B is illustrating for the movement of preferable gyroscope and the non-ideal gyroscope influenceed by quadrature error respectively Property represent；

- Fig. 2 is the simplification top plan view for the known gyroscope that there is quadrature error to compensate；

- Fig. 3 is the schematic cross-section of Fig. 2 gyroscope with quadrature error compensation；

- Fig. 4 shows the simplified electrical circuit diagram of the drive circuit of Fig. 2 and Fig. 3 gyroscope；

- Fig. 5 A and Fig. 5 B show the compensation rate that can be used together with Fig. 2 with Fig. 3 gyroscope；

- Fig. 6 A are the schematic cross-sections of the gyroscope with quadrature error；

- Fig. 6 B are the schematic cross-sections of the embodiment of this gyroscope；

- Fig. 6 C are the details top plan views of Fig. 6 B gyroscope；

- Fig. 7 show the function of the elastic characteristic change as Fig. 6 B gyroscope for expected frequency mismatch value It can be used for the curve of the electronic compensating amount of Fig. 6 B gyroscope；

- Fig. 8 shows that the function of compensation rate and the elastic characteristic change as Fig. 6 B gyroscope is directed to expected frequency The orthogonal Q of compensation of mismatch value_elCurve；

- Fig. 9 shows the curve of the electronic compensating amount as the gyroscope for Fig. 6 B for compensating orthogonal function；

- Figure 10 shows the flow chart of the method for testing of the electronic compensating amount for setting the gyroscope for Fig. 6 B；

- Figure 10 A show the table used in Figure 10 method of testing；

- Figure 11 shows the gyroscope including Fig. 6 B and the block diagram of the equipment of control section；

- Figure 12 shows the circuit diagram of the driving part of Fig. 6 B gyroscope；And

- Figure 13 shows the simplified block diagram of the electronic installation for the gyroscope for combining Figure 11.

Embodiment

As mentioned, the compensating electrode that this gyroscope is designed such that to be intended to eliminate quadrature error is also to frequency mismatch It is adjusted so that this has applied preset value.

Therefore, it is referred to schematically show non-compensation gyroscope 300 and according to one of the present utility model Fig. 6 A and Fig. 6 B with the gyroscope 60 of quadrature error compensation and frequency regulation of embodiment.Gyroscope 300,60 has and figure The 2 and Fig. 3 identical basic structure of gyroscope 10.Then, in Fig. 6 A to Fig. 6 C, the part similar with Fig. 3 those parts By from 100 increased same reference numerals signs and in fig. 6 by from 300 increased same references in Fig. 6 B and Fig. 6 C Label indicates.

(Fig. 6 A) in detail, gyroscope 300 include a pair of removable masses 311,312, and these removable masses exist Extend under inactive state parallel to cartesian space XYZ axle X and Y, driven on the driving direction D1 parallel with axle X, And vibrated due to Coriolis force, so as to the mobile component oriented on the sensing direction D3 parallel with axle Z. Removable mass 311,312 is hinged to centroplasm gauge block 315 via the first spring 316, and be hinged via second spring 326 To fixed structure 327.

Fig. 6 A show influence of the quadrature error to the system of mass 311,312.As shown, quadrature error be by There is component in a direction z, act on two masses 311,312 and generate orthogonal torque M_γParasitic capacity D_eAnd produce 's.

As it can be noticed, by orthogonal torque M_γHalf (the M of value_γ/ 2) put on each removable mass 311, On 312, and orthogonal torque has arm b_γ, the barycenter of the arm and each removable mass 311,312 is away from extending through second The distance of the vertical line of spring 326 is equal.From Fig. 6 A, it is further noted that, such as in U.S. Patent application 2015/ It is described in detail in 0114112, this torque passes through the first spring 316 and centroplasm gauge block due to removable mass 311,312 315 interconnection and cause the rotation of each removable mass in the opposite direction.

Fig. 6 B are shown with the basic structure similar with the basic structure of gyroscope 300 but the top with collocation structure Spiral shell instrument 60.Specifically, gyroscope 60 has compensating electrode 121 to 124, and these compensating electrodes are in removable mass 111,112 Lower extension, and the more accurately opening 117 in removable mass 111,112,118 times extensions.Compensating electrode 121 to 124 With the rectangular shape and size shown in Fig. 6 C, and more accurately there is length L₀(parallel with driving direction D1 On the X of direction) and width p (in direction y).Further, compensating electrode 121 to 124 is arranged to away from removable mass 111st, 112 certain distance a (distance measured in a direction z).

Fig. 6 B further illustrate fixed sensing electrode 130,131, and these fixation sensing electrodes are arranged at corresponding removable Kinoplaszm gauge block 111,112 times and capacitively coupled mass is may move to these.With side that is known and not discussing herein Formula, fix the related output voltage of displacement of the supply of sensing electrode 130,131 to removable mass on sensing direction D3 and believe Number s1, s2, herein, the sensing direction is oriented as parallel with axle Z.

Fig. 6 B also show that compensating electrode 121 to 124 generates on both removable masses 111,112 and be intended to By orthogonal torque M_γIt is arranged to zero compensating torque M_el.In a manner of being not shown and be described below, compensating torque M_elBy four Individual component M_el1To M_el4Superposition provide, each component is generated by corresponding compensating electrode 121 to 124.These components have corresponding Arm b₁、b₂、b₃、b₄, these arms and each compensating electrode 121 to 124 are away from extending through for coupled to fixed structure 127 The distance of the vertical line of corresponding second spring 126 is equal.

Based on these it is assumed that total compensating torque M_elIt is equal to：

M_el=(M_el1+M_el2)-(M_el3+M_el4) [1]

Wherein：

And ε₀It is permittivity of vacuum；L₀, p be the compensating electrode 121 to 124 shown in figure 6 c size；x_dIt is to drive The amplitude of dynamic movement in the direction di；aIt is compensating electrode 121 to 124 and the removable mass 111,112 under inactive state The distance between plane；V_RIt is the voltage applied to centroplasm gauge block 115；V₁、V₂、V₃、V₄It is to be applied to compensating electrode 121 to 124 The offset voltage added；And b₁、b₂、b₃、b₄It is the distance of above-mentioned compensating electrode 121 to 124.

By setting b₁=b₄And b₂=b₃And apply offset voltage V₁=V₃And V₂=V₄, we obtain：

ConsiderAccording to aforementioned equation, compensating torque is provided by below equation：

Compensating torque M_elIt can be used for quadrature error Q_γCaused orthogonal torque M_γIt is arranged to zero, generation and compensating torque M_elThe orthogonal Q of proportional compensation_el.It is possible thereby to write as：

Q_el=k_Q[(V_R-V₁)²-(V_R-V₂)²] [3]

Wherein,It is that will compensate orthogonal Q_elThe compensating torque M orthogonal with generation compensation_elContact The proportionality constant come.

As it can be noticed, compensate orthogonal Q_elDepending on offset voltage V₁、V₂.Therefore, by compensating electrode 121 with Apply the differential voltage Δ V equal with the differential voltage applied between compensating electrode 123 and 124 between 122, it is possible to generate Cause depending on the mobile x of driving_dAnd depend on offset voltage V₁、V₂Compensating torque M_elElectrostatic force.This electrostatic force is thus It can be used for eliminating orthogonal torque according to below equation：

M_el+M_γ=0 [4]

The equation, which corresponds to, to be caused：

Q_el+Q_γ=0 [4 ']

Go out as shown below, by V₁With V₂Between relation appropriate selection, via compensating electrode 121 to 124, it is further possible to regulating frequency mismatch.

In fact, apply offset voltage V to compensating electrode 121 to 124₁To V₄The system of mass 111,112 is determined The change of proof resilience constant, and thereby determined that resonant frequency f_s.Specifically, resonant frequency f_sProvided by below equation：

Wherein, J is moment of inertia, K_mIt is mechanical elasticity constant, K_{el_s}It is due to be sensed in centroplasm gauge block 115 with fixed The electrical potential difference that applies between electrode 130,131 (Fig. 6 B) and caused electrostatic elastic constant, and K_{el_q}It is due in centroplasm The differential voltage that applies between gauge block 115 and compensating electrode 121,122,123,124 and caused electrostatic elastic constant.

Specifically, electrostatic elastic constant is provided by below equation：

Consider V₁=V₃And V₂=V₄, we obtain：

Wherein

As can be seen that the voltage change on electrode 121 to 124 needs resonant frequency f from equation [6]_sChange.By This, frequency mismatch Δ f₀It is equal to：

Indicate

And equation [6] is substituted into equation [7], we obtain

It should be noted that in equation [9], ω_S0It is when with V_RSense when being biased to compensating electrode 121 to 124 Survey resonant frequency.

Equation [3] shows, because two in square brackets subtract each other, compensates orthogonal Q_elDepending on electrode 121 to 124 it Between differential voltage.On the contrary, equation [9] shows, because identical two additions, frequency mismatch Δ f in square brackets₀Depend on The common-mode voltage of these electrodes.Subsequently, for given quadrature error Q_γ, it is possible to find compensating the quadrature error and make top Spiral shell instrument 60 can be with desired frequency mismatch Δ f₀The single pair offset voltage V that value is operated₁And V₂Value.

For predeterminated frequency mismatch value Δ f₀(herein, 1kHz) and for 2% increment of theoretical expected value from- 12% (for bottom curve) to 12% (for top curve) increased different elastic constant k_sValue, it is contemplated that show to figure The offset voltage V that compensating electrode 121 to 124 in 6B gyroscope 60 applies₁、V₂The ratio between Fig. 7 and Fig. 8, this is especially clear 's.

It is to be noted that Fig. 7 and Fig. 8 curve is with applying offset voltage V₁、V₂It is corresponding, the life of these offset voltages It is equal to Q into modulus_γAnd contrary sign the orthogonal Q of compensation_elAnd follow rule represented in Fig. 9.As it can be noticed, according to Frequency mismatch and the curve of offset voltage that applies is linear no longer as in Fig. 5 A, it is but secondary, and common mode electricity Pressure is no longer constant.

The method of testing for this gyroscope is described below.In fact, equation [9] has three unknown numbers：Driving Frequency f_d, the driving frequency may change on design load；Sense resonance frequency omega_S0；And k_s/J.In these unknown numbers In, can be with direct measurement f_d, and can be by applying appropriate offset voltage V₁、V₂And measurement frequency mismatch Δ f₀Come indirect Measure ω_S0And k_s/J。

Know these three variables f_d、ω_S0And k_s/ J and seek to provide predeterminated frequency mismatch Δ f_0dThe benefit of (herein, 1kHz) Repay voltage V₁、V₂Value pair, it is possible to understand which bar curve in Fig. 7 curve describes the row of the specific gyroscope 60 in test For, i.e. which bar curve is the elastic constant k for influenceing this gyroscope_sChange.Curve and the bullet that thereby determines that using Fig. 8 Property constant k_sValue percentage change, it is possible to it is determined that eliminating quadrature error Q_γThe first offset voltage V₁Value.It is possible thereby to Curve again according to mark before Fig. 7 or the second offset voltage V of acquisition according to equation [9]₂Value.

According to the one side of this specification, during test, being tested to determination to each gyroscope 60 will grasp The offset voltage V applied during work₁、V₂Value.Specifically, test program may comprise steps of (also referring to Figure 10 flow Figure)：

- measurement driving frequency f_d, step 200；

- by applying offset voltage V appropriate as indicated above₁、V₂Value measures sensing resonance frequency omega indirectly_S0 With parameter k_s/ J, step 202；

- obtain expected frequency mismatch Δ f_0d(this value and system gain are negatively correlated, and are generally consolidated in the design phase for value It is fixed), step 204；

- with step delta V (for example, 1V, from 1V to V_R(such as 10V)) apply multiple offset voltage V₁、V₂Value, and measure Corresponding frequencies mismatch Δ f₀Value；Thus obtained frequency mismatch Δ f₀Value is for example stored in the indicative table 220 shown in Figure 10 A In, step 206；

- searched in table 220 by expected frequency mismatch Δ f_0dThe point that value characterizes, step 208；In practice, these are put Set expression and the elastic constant k that the gyroscope in test may be applied_sThe corresponding curve of change (shown from Fig. 7 Curve among)；

Among the set of-point identified in a step 208, mark generation compensates orthogonal Q_elThe first offset voltage V₁'s Point value, the compensation is orthogonal to compensate quadrature error Q on the basis of equation [3] and equation [4]_γ, step 210；

The second offset voltage V is identified in-the curve identified from step 208 or using equation [9]₂Point value, Step 212；And

- by offset voltage V₁、V₂Value is to being stored in the associated with the gyroscope in test of Figure 11 descriptions as described below in references to Memory in, step 214.

Figure 11 shows the block diagram of the electronic equipment 100 using frequency mismatch compensation principle described above.

In fig. 11, electronic equipment 100 includes gyroscope 60 (herein, being represented via its functional block) and control element 65.

Gyroscope 60 is integrated in the semiconductor chip 70 schematically shown and with identical with Fig. 2 gyroscope 10 Structure.Therefore, the element of reference picture 6B descriptions is indicated by same reference numerals.In detail, centroplasm gauge block 115 is anchored into not The substrate (similar with Fig. 6 B substrate 125) shown, the centroplasm gauge block can be around the axles of (parallel with axle Z) vertical with gyroscope 60 Rotate and extend through center C.Centroplasm gauge block 115 via the first spring 116 coupled to four removable masses 111 to The only one being shown more in detail in 114, Figure 11 in this four removable masses may move mass (removable mass 117).Removable mass 111 to 114 is relative to center C asymmetrical arrangement and the top with such as Fig. 2 under static state in couples The plotting planes (plane XY) of spiral shell instrument extend parallel to.Removable mass 111 to 114 has two frees degree and is subjected to edge The powered motion of respective drive and it is subjected to that there is the sensing movement of component along the corresponding sensitive axis vertical with drive shaft.With this Thus mode known to body, removable mass 111 to 114 have similar but are configured for detection around out-of-alignment shifting Dynamic basic structure.It is subject to necessary change, thus this specification only relates to the removable mass 111 illustrated in greater detail, It is also possible to may move mass 112 to 114 applied to other.

Specifically, may move mass 111 be subjected to along the drive shaft D1 parallel with axle X powered motion and be subjected to along with Sensitive axis D3 parallel axle Z has the sensing movement of component.

Herein, schematically shown by rigidly connected sensing mass 72 and compensation mass 73 relative to each other Removable mass 111.General trapezoidal shape as shown in Figure 2 can be had by sensing mass 72.Compensation mass 73 has There is general hollow rectangular shape, cover 121,122 pairs of compensating electrode.Specifically, opening 117 is formed in compensation mass 73 simultaneously And there are two side 117A, the 117Bs parallel with axle Y.Each corresponding side surface of the compensating electrode 121,122 along opening 117 117A, 117B extend, and half is in compensation mass 73 times and half is under opening 117.

Removable mass 111 is connected in driving direction via the second spring 76 for allowing for sensing movement The actuating module 77 of removable mass 111 is driven on D1, and is moved by the 3rd spring 78 to be connected to be used to sense to drive Dynamic 79 have a detection effectively driving parameter (including driving frequency f as discussed above_d) task module.

Actuating module 77 and the module for sensing driving mobile 79 are connected to the driving control being formed in control element 65 Molding block 85.Control element 65 is generally integrated in different chips 90 and including such as ASIC (application specific integrated circuit).

Control element 65 further comprises being connected to the sensing module 88 of sensing electrode 130, storage as discussed above The offset voltage V calculated during test₁、V₂Parameter storage 91, DAC 92 and the buffer 93 of value.DAC 92 forms voltage Source, each voltage source are configured for applying offset voltage V₁、V₂, these offset voltage values are specified by the content of memory 91.

For example, each DAC 92 and associated buffer 93 can be arranged by mode as shown in Figure 12.In reality In trampling, in the embodiment illustrated, DAC 92 is by being coupled in reference voltage V_{With reference to}It is between mass and including multiple electricity The resistance divider 95 of resistance device 96 is formed, and these resistors can be opened by what is driven on the basis of the content of memory 91 Close 97 and be coupled to buffer 93.

MEMS gyroscope 60 described herein is so that can use the identical electrodes of regulation quadrature error to use Electrostatic means carry out regulating frequency mismatch and thus have the size reduced and low consumption horizontal.

Figure 13 illustrate it is with reference to electronic equipment 100 and can such as palmtop computer (personal digital assistant, PDA), may have the laptop computer or portable computer, cell phone, messaging devices, numeral of wireless capability Music player, digital camera or be designed to handle, store, transmitting or the device such as other devices of receive information in A part for the electronic system 400 used.For example, electronic equipment 100 can be used in digital camera to detect mobile and hold Row image stabilization.In a possible embodiment, electronic equipment 100 is included in the motion for computer or video game console In the user interface of activation.In a further embodiment, electronic equipment 100 is incorporated in satellite navigation, and in satellite Positioning signal is used for temporary position in the case of losing and tracked.

Figure 13 electronic system 400 includes control unit 410, input/output (I/O) unit 420 (for example, keyboard or aobvious Show device), electronic equipment 100, wave point 440 and volatibility or non-volatile types of memory 460, these parts pass through bus 150 and it is coupled to each other.Alternately, memory 460 may be at the inside of control unit 410 or can substitute in Figure 11's Memory 91 and storage inside control element 90 can be used for the parameter and amount of operation electronic equipment 100, such as offset voltage V₁、 V₂Deng.In one embodiment, battery 480 can be used for powering to system 400.However, electronic system 400 even can be wrapped only Include some units in the unit shown in Figure 13.

Control unit 410 can include such as one or more microprocessors, microcontroller.In different embodiments, It can be with the function of the control element 90 of integration map 11, and Figure 13 electronic equipment 100 can be formed by gyroscope 60.

I/O units 420 can be used for generating message.System 400 can pass through radio frequency (RF) signal using wave point 440 Come to from cordless communication network (not shown) launch and receive message.The example of wave point can include antenna, such as dipole The wireless transceivers such as antenna, although the scope of the utility model not limited to this.Further, I/O units 420 can provide expression The voltage of the content stored is as numeral output (if having stored digital information) or as simulation output (if Stored analog information).

Finally it is clear that described herein and displaying gyroscope, control method and adjusting method can be made Modifications and variations, without thus departing from the scope of the utility model as limited in the following claims.

Claims (6)

1. A kind of 1. MEMS gyroscope (60,100), it is characterised in that including：

   Supporting construction (125,127)；

   Mass (111-114), the mass driving direction (D1) perpendicular to one another and sensing direction (D3) on relative to The supporting construction be may move, and the removable mass is influenceed by quadrature error caused by orthogonal torque；

   Driving structure (77), the driving structure are described removable to be controlled with driving frequency coupled to the removable mass Movement of the kinoplaszm gauge block on the driving direction；

   Motion sensing electrode (130), the motion sensing electrode is coupled to the removable mass, described removable to detect Movement of the kinoplaszm gauge block on the sensing direction；And

   Quadrature compensation electrode (121-124), the quadrature compensation electrode are coupled to the removable mass, to generate and institute State the opposite compensating torque of orthogonal torque；

   The removable mass has a variable resonant frequency, and the difference of the resonant frequency and the driving frequency is that frequency is lost Match somebody with somebody；

   The gyroscope is configured for being biased the quadrature compensation electrode using offset voltage, so as to default Frequency mismatch drives the removable mass.
2. 2. gyroscope as claimed in claim 1, it is characterised in that the offset voltage can be secondary with the quadrature error Change.
3. 3. gyroscope as claimed in claim 1, it is characterised in that the quadrature compensation electrode (121-124) is including first just Compensating electrode and the second quadrature compensation electrode, the first quadrature compensation electrode and the second quadrature compensation electrode is handed over to be configured Into for respectively with the first offset voltage V₁With the second offset voltage V₂And biased, wherein, V₁And V₂It is selected for meeting Equation：

   <mrow> <msub> <mi>&amp;Delta;f</mi> <mn>0</mn> </msub> <mo>=</mo> <mfrac> <mn>1</mn> <mrow> <mn>2</mn> <mi>&amp;pi;</mi> </mrow> </mfrac> <msqrt> <mrow> <msubsup> <mi>&amp;omega;</mi> <mrow> <mi>s</mi> <mn>0</mn> </mrow> <mn>2</mn> </msubsup> <mo>-</mo> <mfrac> <msub> <mi>k</mi> <mi>S</mi> </msub> <mi>J</mi> </mfrac> <mo>&amp;lsqb;</mo> <msup> <mrow> <mo>(</mo> <msub> <mi>y</mi> <mi>R</mi> </msub> <mo>-</mo> <msub> <mi>V</mi> <mn>1</mn> </msub> <mo>)</mo> </mrow> <mn>2</mn> </msup> <mo>+</mo> <msup> <mrow> <mo>(</mo> <msub> <mi>V</mi> <mi>R</mi> </msub> <mo>-</mo> <msub> <mi>V</mi> <mn>2</mn> </msub> <mo>)</mo> </mrow> <mn>2</mn> </msup> <mo>&amp;rsqb;</mo> </mrow> </msqrt> <mo>-</mo> <msub> <mi>f</mi> <mi>d</mi> </msub> </mrow>

   Wherein：

   Δf₀It is the predeterminated frequency mismatch；

   V_RIt is the bias voltage of the removable mass (111-114)；

   ω_S0It is the resonant frequency of the removable mass；

   Ks/J is the parameter related to the mechanical constant of the removable mass；And

   f_dIt is the driving frequency.
4. 4. gyroscope as claimed in claim 3, it is characterised in that the first offset voltage V₁With second offset voltage V₂Meet equation：

   Q_el+Q_γ=0

   Wherein：

   Q_elIt is that the compensation provided by below equation is orthogonal：

   Q_el=k_Q[(V_R-V₁)²-(V_R-V₂)²],

   Q_γIt is the quadrature error,

   k_qIt is by the orthogonal Q of compensation_elWith the compensating torque M_elThe proportionality constant connected.
5. 5. the gyroscope as any one of Claims 1-4, it is characterised in that described to deposit including memory component (91) Memory element is configured for storing the value of the offset voltage.
6. 6. a kind of electronic system, it is characterised in that including control unit (410) and according to any one of claim 1 to 5 institute The MEMS gyroscope (60) stated, the MEMS gyroscope are coupled to described control unit (410).