CN208766198U - Piezoelectric vibration motivates self diagnosis mems accelerometer watch core and accelerometer - Google Patents

Abstract

The utility model discloses a kind of piezoelectric vibration excitation self diagnosis mems accelerometer watch core and accelerometer.The accelerometer watch core includes: top crown, middle plate, bottom crown and shake table, the middle plate is located at the top crown and the bottom crown middle, the middle plate is connected to fixed position by an overarm, the top crown and the middle plate constitute first capacitor, the bottom crown and the middle plate constitute the second capacitor, and the first capacitor and second capacitor constitute a pair of of differential capacitance；The shake table includes feedback layer and vibration level, and the feedback layer is located on the downside of the bottom crown, and the vibration level is located on the downside of the feedback layer；The feedback layer surface draws feedback output positive electrode and feedback output negative electrode, and the vibration layer surface draws driving positive electrode and driving negative electrode.It can be realized the detection to vibration level Oscillation Amplitude using the watch core and accelerometer of the utility model.

Description

Piezoelectric vibration motivates self diagnosis mems accelerometer watch core and accelerometer

Technical field

The utility model relates to multilayer piezoelectric ceramic fabricating technology fields, motivate more particularly to a kind of piezoelectric vibration Self diagnosis mems accelerometer watch core.

Background technique

MEMS (Micro Electro-Mechanical System) accelerometer is weight in microminiature inertial navigation system One of sensor wanted.Have the characteristics that it is small in size, at low cost, light-weight and low in energy consumption, modern military equip short distance system It leads, integrated navigation, gesture stability, motor vehicles for civilian use and consumer electronics market etc. are widely applied.

Mems accelerometer is due to by environment temperature, air pressure, mechanical couplings, residual stress release, watch core mechanical/thermal stress Etc. factors influence, cause its long-time stability poor, and after being installed, the health status of accelerometer can not be carried out real When diagnose.Therefore mems accelerometer self-test survey technology is one of the key technology for improving mems accelerometer long-time stability.

Currently, the self diagnosis detection technique of mems accelerometer is broadly divided into two classes: first is that built-in in mems accelerometer Self-detection circuit, external input pumping signal make sensitive structure generate response completion diagnosis detection by self-detection circuit； Second is that embedding micro-structure vibration source in mems accelerometer, vibration is generated by dynamic excitation signal, realizes self diagnosis detection.

, to State Intellectual Property Office, an application is applied on March 21st, 2016 in Suzhou Internet of Things research and development center Number be CN105823907A, entitled " parallel plate capacitor type mems accelerometer built-in self-test circuit and self-test method " Patent of invention, the invention belong to first kind self diagnosis detection technique, provide a kind of parallel plate capacitor type mems accelerometer Built-in self-test circuit and a kind of self-test method provide electric excitation to parallel plate capacitor accelerometer, by capacitance sensing mould The signal of block output amplifies, analog-to-digital conversion and digital processing, according to the self-test supply voltage and electricity under different condition The output response for holding sensing module analyzes its sensitivity, to realize in the sensitivity progress to parallel plate capacitor type accelerometer Build self-test.The invention has optimized the influence of external environment and parasitic capacitance to output signal, improves the standardization journey of test Test and product cost is effectively reduced to the dependency degree of complicated test equipment in degree, reduction.

In addition, ADI in 2017 be proposed two dedicated industrial state-detection accelerometer ADXL1001 and ADXL1002, this two accelerometer has complete electrostatic self-test and outranges index, but its electrostatic self-test survey technology needs Accelerometer is wanted to be detached from working condition, by applying excitation detection voltage in self-test pin, by curve of output and default setting Curve comparison completes self-test.

Although the above-mentioned prior art solves the problems, such as the dependency degree to complicated test equipment, but there is problems: Firstly, its pumping signal acts on comb teeth or parallel plate capacitor structure, the health of mems accelerometer sensitive structure can not be detected State；Secondly, it can only carry out self-test to the sensitivity of mems accelerometer, it is unable to get mems accelerometer sensitive structure Characteristic parameter (quality factor and resonance frequency)；Finally, the inspection of mems accelerometer packaging air tightness health status can not be obtained It surveys.

Chinese gongwu research electronic engineering research institute is in 29 Xiang State Intellectual Property Office December in 2016, application One application No. is CN106771366A, entitled " a kind of's mems accelerometer health status detection device and monitoring method " Patent of invention, the invention belong to the second class self diagnosis detection technique, and device includes: micro-vibration platform, peripheral platform, four water Flat supporting beam, four vertical support beams；Micro-vibration platform be it is rectangular, peripheral platform is located at the periphery of micro-vibration platform；Four water Flat supporting beam and four vertical support beams are located between micro-vibration platform and peripheral platform；One end of each horizontal shore connects Right-angle structure is formed to one end of corresponding vertical support beam, and with vertical support beam；Four right-angle structures are along clockwise direction Successively it is evenly distributed on the surrounding of micro-vibration platform；The horizontal shore and vertical support beam of each right-angle structure are respectively at micro- vibration Two sides aligned parallels of moving platform；One section of horizontal shore of each right-angle structure is connect with peripheral platform, vertical support beam one End is connected to the middle part of corresponding micro-vibration platform edges.The device and method of the invention may be implemented mems accelerometer and survey Measure health status monitoring when higher accelerations.

Although the above-mentioned prior art has the advantages that the monitoring and high integration of health status when to high acceleration, also There are problems that: firstly, the envelope of the micro-vibration platform of the health status monitoring device and peripheral platform and mems accelerometer Casing is mutually indepedent, and process for machining and manufacturing has larger difficulty；Secondly, micro-vibration platform material and encapsulating material are inconsistent, material Expect that stress influence is larger, mechanical property generates variation, and leading to excitation output, there may be drifts；Finally, micro-vibration platform structure This can occur movement with mems accelerometer sensitive structure and couple, to reduce environmental suitability as movable member.

Summary of the invention

The purpose of the utility model is to provide a kind of piezoelectric vibration excitation self diagnosis mems accelerometer watch core and acceleration Meter, solves micro-vibration platform and couples with the movement between sensitive structure, and difficulty of processing is big, environmental suitability is poor, poor reliability etc. is asked Topic realizes the miniaturization high integration, broadband, multi-parameter, the inspection of high speed real time health state self diagnosis of mems accelerometer It surveys.

To achieve the above object, the utility model provides following scheme:

A kind of piezoelectric vibration motivates self diagnosis mems accelerometer watch core, the accelerometer watch core include: top crown, in Between pole plate, bottom crown and shake table, the middle plate is located at the top crown and the bottom crown middle, the dynode Plate is connected to fixed position by an overarm, and the top crown and the middle plate constitute first capacitor, the bottom crown The second capacitor is constituted with the middle plate, the first capacitor and second capacitor constitute a pair of of differential capacitance；The vibration Dynamic platform includes feedback layer and vibration level, and the feedback layer is located on the downside of the bottom crown, and the vibration level is located at the feedback layer Downside；The feedback layer surface draws feedback output positive electrode and feedback output negative electrode, and the vibration layer surface draws driving Positive electrode and driving negative electrode.

Optionally, the feedback layer and the vibration level are all made of the preparation of low-temperature co-fired ceramics technique.

Optionally, the top crown, the middle plate and the bottom crown equal length.

Optionally, the top crown, the middle plate and the bottom crown are arranged in parallel.

Optionally, the top crown and middle plate face setting, the bottom crown and the middle plate face Setting, the top crown and bottom crown face setting.

To achieve the above object, the utility model provides following scheme:

A kind of accelerometer applied to piezoelectric vibration excitation self diagnosis mems accelerometer watch core, the accelerometer packet It includes: watch core, charge amplifier circuit, charge transport circuit, charge integrator circuits and shake table closed-loop driving circuit, the table The output end of core middle plate is connect with the input terminal of the charge amplifier circuit, the output end of the charge amplifier circuit It is connect with the input terminal of the charge transport circuit, output end and the charge integrator circuits of the charge transport circuit Input terminal connection, the watch core, the charge amplifier circuit, the charge transport circuit and the charge integrator circuits structure At negative feedback loop；The shake table part of the watch core is connect with the shake table closed-loop driving circuit.

Optionally, the charge amplifier circuit includes: clock pins, the first charge amplifier and third capacitor, described Clock includes the first clock pins and second clock pin, anode and the second clock pin of first charge amplifier Connection, the cathode of first charge amplifier are connect with first clock pins, and the capacitor is put with first charge Big device is connected in parallel, and first clock pins are connect with the output end of first charge amplifier.

Optionally, the charge transport circuit includes: the 4th capacitor and clock, the clock include the first clock pins and Second clock pin, the input terminal of the 4th capacitor and output end respectively with first clock pins and the second clock Pin connection.

Optionally, the charge integrator circuits include: the first charge integrator and the 5th capacitor, and first clock draws Foot is connect with the cathode of first charge integrator, the plus earth of first charge integrator, the first charge product Device is divided to be connected in parallel with the 5th capacitor.

Optionally, the shake table closed-loop driving circuit includes: the second gain amplifier, subtracter, multiplier, the second electricity Lotus integrator, variable gain amplifier and voltage controlled oscillator；The input terminal of external reference circuit is defeated with the subtracter respectively Enter end to connect with the voltage controlled oscillator input terminal, the input terminal of the output end of the voltage controlled oscillator and the multiplier connects It connects, the output end of the subtracter is connect with the output end of second charge integration amplifier respectively, the second charge product Divide the plus earth of amplifier, the cathode of second charge integration amplifier is connect with the vibration level, second gain The output end of amplifier is connect with the vibration level, and the anode of second gain amplifier is connect with the multiplier, described The cathode of second gain amplifier is grounded.

According to specific embodiment provided by the utility model, the utility model discloses following technical effects: this is practical new Type provides a kind of piezoelectric vibration excitation self diagnosis mems accelerometer watch core, after experiencing acceleration, since inertia force acts on, Movable plate will deviate from construction geometry symmetric position.At this point, intermediate middle plate to top crown distance be (d₀+ X), arrive bottom crown Distance is (d0-X).Total capacitance between middle plate and top crown is C1, total electricity between intermediate movable plate and bottom crown Holding is C2.Capacitor C1 and C2 constitute a pair of of differential capacitance.The vibration level of embedded piezoelectric vibration generator system is experienced by driving electrodes pair Input driving voltage when, due to inverse piezoelectric effect, ceramic crystal generates strain under electric field action, so as to cause accelerometer Top crown, bottom crown, middle plate and feedback layer vibration.Feedback layer then utilizes piezoelectric effect, generate with suffered by ceramic crystal The linear voltage signal of stress is, it can be achieved that detection to vibration level Oscillation Amplitude.

Detailed description of the invention

In order to illustrate the embodiment of the utility model or the technical proposal in the existing technology more clearly, below will be to embodiment Needed in attached drawing be briefly described, it should be apparent that, the accompanying drawings in the following description is only the utility model Some embodiments for those of ordinary skill in the art without any creative labor, can also basis These attached drawings obtain other attached drawings.

Fig. 1 is that the utility model embodiment piezoelectric vibration motivates self diagnosis mems accelerometer watch core schematic diagram；

Fig. 2 is that the utility model embodiment piezoelectric vibration motivates self diagnosis mems accelerometer watch core composition schematic diagram；

Fig. 3 is that the utility model embodiment piezoelectric vibration motivates self diagnosis mems accelerometer internal circuit connection figure；

It is the embedded driving source self diagnosis accelerometer outline structural diagram of inventive embodiments in Fig. 4；

Fig. 5 is the embedded piezoelectric vibration generator system electrode schematic diagram of the utility model embodiment.

Specific embodiment

The following will be combined with the drawings in the embodiments of the present invention, carries out the technical scheme in the embodiment of the utility model Clearly and completely describe, it is clear that the described embodiments are only a part of the embodiments of the utility model, rather than whole Embodiment.Based on the embodiments of the present invention, those of ordinary skill in the art are without making creative work Every other embodiment obtained, fall within the protection scope of the utility model.

To keep the above objects, features, and advantages of the utility model more obvious and easy to understand, with reference to the accompanying drawing and have Body embodiment is described in further detail the utility model.

Fig. 1 is that the utility model embodiment piezoelectric vibration motivates self diagnosis mems accelerometer watch core schematic diagram.Fig. 2 is this Utility model embodiment piezoelectric vibration motivates self diagnosis mems accelerometer watch core composition schematic diagram.A kind of piezoelectric vibration excitation from Mems accelerometer watch core is diagnosed, as depicted in figs. 1 and 2, the accelerometer watch core includes: sensitive structure (110) and vibration Platform (120), the sensitive structure (110) include top crown (111), middle plate (112), bottom crown (113), the dynode Plate (112) is located at the top crown (111) and the bottom crown (113) middle, and the middle plate (112) is outstanding by one Beam is connected to fixed position, and the top crown (111) and the dynode (112) plate constitute first capacitor, the bottom crown (113) the second capacitor is constituted with the middle plate (112), the first capacitor and second capacitor constitute a pair of of differential electrical Hold；The shake table includes feedback layer (121) and vibration level (122), and the feedback layer (121) is located at the bottom crown (113) Downside, the vibration level (122) are located on the downside of the feedback layer (121)；Drawing feedback output just in feedback layer (121) surface Electrode (123) and feedback output negative electrode (124), the vibration layer surface draw driving positive electrode (125) and driving negative electrode (126)。

The feedback layer (121) and the vibration level (122) are all made of the preparation of low-temperature co-fired ceramics technique.

The top crown (111), the middle plate (112) and the equal length of the bottom crown (113) and it is parallel just To setting.

The equal spacing of construction geometry symmetric position and upper bottom crown (111) and (113) is d0.Experiencing acceleration Afterwards, since inertia force acts on, movable plate (112) will deviate from construction geometry symmetric position (diagram dotted line position).At this point, intermediate Movable plate (112) to top crown (111) distance be (d0+X), to bottom crown 130 apart from for (d0-X).Intermediate movable plate with Total capacitance between top crown is C1, and the total capacitance between intermediate movable plate and bottom crown is C2.Capacitor C1 and C2 constitute one To differential capacitance.The vibration level (122) of embedded piezoelectric vibration generator system (120), which is experienced, inputs (125-126) by driving electrodes When obtaining driving voltage, due to inverse piezoelectric effect, ceramic crystal generates strain under electric field action, so as to cause accelerometer sensitive Structure (110) and feedback layer (121) vibration.Feedback layer (121) then utilize piezoelectric effect, generate with ceramic crystal suffered by stress at The voltage signal of linear relationship is, it can be achieved that detection to vibration level (122) Oscillation Amplitude.

Piezoelectric vibration motivates the accelerometer of self diagnosis mems accelerometer watch core, and the accelerometer includes: watch core, electricity Lotus amplifier circuit, charge transport circuit, charge integrator circuits and shake table closed-loop driving circuit, the watch core middle plate Output end connect with the input terminal of the charge amplifier circuit, the output end of the charge amplifier circuit and the charge The input terminal connection of circuit is transported, the output end of the charge transport circuit and the input terminal of the charge integrator circuits connect It connects, the watch core, the charge amplifier circuit, the charge transport circuit and the charge integrator circuits constitute negative-feedback Circuit；The shake table part of the watch core is connect with the shake table closed-loop driving circuit.

The charge amplifier circuit includes: clock pins, the first charge amplifier and third capacitor, and the clock includes The anode of first clock pins and second clock pin, first charge amplifier is connect with the second clock pin, institute The cathode for stating the first charge amplifier is connect with first clock pins, and the capacitor is in parallel with first charge amplifier Connection, first clock pins are connect with the output end of first charge amplifier.

The charge transport circuit includes: the 4th capacitor and clock, when the clock includes the first clock pins and second Clock pin, the input terminal and output end of the 4th capacitor connect with first clock pins and the second clock pin respectively It connects.

The charge integrator circuits include: the first charge integrator and the 5th capacitor, first clock pins and institute State the first charge integrator cathode connection, the plus earth of first charge integrator, first charge integrator with 5th capacitor is connected in parallel.

The shake table closed-loop driving circuit includes: the second gain amplifier, subtracter, multiplier, the second charge integration Device, variable gain amplifier and voltage controlled oscillator；The input terminal of external reference circuit respectively with the input terminal of the subtracter and The voltage controlled oscillator input terminal connection, the output end of the voltage controlled oscillator is connect with the input terminal of the multiplier, described The output end of subtracter is connect with the output end of second charge integration amplifier respectively, second charge integration amplifier Plus earth, the cathode of second charge integration amplifier connect with the vibration level, second gain amplifier Output end is connect with the vibration level, and the anode of second gain amplifier is connect with the multiplier, second gain The cathode of amplifier is grounded.

Fig. 3 is that the utility model embodiment piezoelectric vibration motivates self diagnosis mems accelerometer internal circuit connection figure.It is embedding Entering formula driving source self diagnosis accelerometer detection circuit (200) is a typical charge self-balancing switched capacitor open loop detection Circuit, entire circuit are mutually made of Φ 1 with 2 two clocks of Φ.

Sensitive structure (110) equivalent circuit link (410), wherein (111), (112) and (113) are respectively upper in Fig. 1 Pole plate, intermediate movable plate, bottom crown, C1 and C2 are the differential capacitance pair in micro-acceleration gauge sensitive structure.In 1 clock of Φ Phase, top crown (111) are connected to positive supply VS, and bottom crown (113) is connected to negative supply-VS, and intermediate movable plate (112) is connected to operation

Amplifier A2 exports VM, and positive-negative power charges to differential capacitance pair C1 and C2.In 2 clock phase of Φ, upper and lower pole plate (111) and (113) are connected to operational amplifier A2 output VM, and intermediate movable plate (112) is connected to operational amplifier A1 reverse side.This When, since operational amplifier A1 void is short, reverse side is equal with in-phase end voltage, be also VM, that is, differential capacitance pair top crown (111), Intermediate movable plate (112), bottom crown (113) electrode voltage are equal, the electric charge transfer that differential capacitance pair C1 and C2 are filled with.

Charge amplifier (420) collects the charge of sensitive structure differential capacitance pair C1 and C2 transfer.In 1 clock phase of Φ, instead Feed holds C3 and is switched on and off short circuit reset.In 2 clock phase of Φ, movable plate among operational amplifier A1 reverse side and sensitive structure (112) it is connected.The charge on differential capacitance pair C1 and C2 starts transfer electric discharge at this time, and feedback capacity C3 collects the charge of transfer.

Charge transport link (430) is made of a capacitor C4 and four switches.Connect respectively at 1 both ends clock phase C4 Φ Be connected to and operational amplifier A2 backward end.Know that operational amplifier A2 backward end is ground level, the i.e. both ends capacitor C4 by void is short Voltage is equal, and capacitor C4 discharges at this time.In 2 clock phase of Φ, capacitor C4 is coupled with operational amplifier A1 output and calculates amplifier A2 exports VM.Operational amplifier A1 has charge due to collecting on C4 to generate output voltage Vo, is pre-charged to capacitor C4.Capacitor Two electrode plates of C4 need and switch accurate fit, so that charge integrator operational amplifier A2 output feedback network (450) is Negative-feedback.

Charge integrator (440), 1 clock phase reverse input end of Φ meet capacitor C4, collect the charge of its release and accumulate to it Point.1 clock phase reverse input end of Φ and C4 are disconnected, and operational amplifier A2 output is kept.

Operational amplifier A2 output is fed back to capacitor C4 and operational amplifier A1 and sensitivity by negative feedback loop (450) Structure top crown (111), intermediate movable plate (112), bottom crown (113).Since charge integrator (440) act on, constitute deep Negative-feedback is spent, realizes that charge self-balancing is the effect in 1 clock phase supply voltage VS of Φ ,-VS and operational amplifier A2 output VM Under, differential capacitance pair C1 and C2 charging total amount are 0.

At this point, having formula (1) establishment, i.e.,

C1 (VM-VS)+C2 (VM+VS)=0 (1)

It can be obtained shown in accelerometer (200) output VM such as formula (2) by formula (1).

That is the amount of accelerometer detection is (C1-C2)/(C1+C2)

As shown in Figure 1, ideally, by parallel plate capacitor formula, the size of C1 and C2 are respectively such as formula (3) and (4) institute Show.

Wherein A and ε is respectively polar plate area and dielectric constant.By formula (3) and (4) bring into formula (2) and arrange can obtain it is as follows Input/output relation:

I.e. output voltage is directly proportional to middle plate displacement x, and middle plate is displaced with inertia force (acceleration) at just Than, therefore charge self-balancing accelerometer output voltage VM and acceleration are linear.

Embedded piezoelectric vibration generator system closed-loop driving circuit (460), controls pressure for the reference voltage Vref externally supplied all the way It controls oscillator Osc and generates the voltage signal that frequency is fs；Another way is anti-by subtracter and embedded piezoelectric vibration generator system (120) Feedback output electrode subtracts each other (123-124) feedback voltage exported, which enters variable gain amplifier VGA, Two paths of signals enters gain amplifier A3 after multiplier M multiplication and amplifies to obtain frequency to be fs, and amplitude is the embedded piezoelectricity of Vd Shake table (120) drive voltage signal VD, the signal are input to the driving electrodes of embedded piezoelectric vibration generator system (120) to (125- 126) driving multilayer piezoelectric ceramic vibration level (122) generates vibration.The vibration that multilayer piezoelectric ceramic vibration level (122) generates makes one Aspect makes feedback layer (121) to generate deformation and then generates feedback detectable voltage signals by feedback detecting electrode to (123-124) It is input to charge integration amplifier A4, obtains feedback voltage signal Vfb, the closed loop for forming embedded piezoelectric vibration generator system (120) is driven Rotating ring road；On the other hand, multilayer piezoelectric ceramic vibration level (122) generate vibration make accelerometer sensitive structure (100) by Inertia force effect, by detection circuit (200), can be detected to obtain the output voltage signal linear with acceleration.It can Change and detect output voltage signal by fixed step size by process control reference voltage Vref, detection output electricity can be established Relationship between pressure and driving voltage frequency fs, the corresponding driving voltage frequency fs of detection output voltage maximum point are to add The intrinsic frequency of speedometer.For accelerometer, obtained by measurement sensitive structure (100) intrinsic frequency using mechanical equation The parameter as system equation is obtained into detection output and calibration factor S to rigidity k and damped coefficient.

Similarly, according to characteristic quantity, (mapping relations between Q value and intrinsic frequency f) and air pressure, test volume are Quality factor q and resonance frequency, using damping characteristic, damped coefficient c obtains the coefficient of viscosity according to hydrodynamics.With environment pressure By force, temperature is related, it is possible thereby to air pressure change be judged, to realize the diagnosis of hermetic properties.

It is the embedded driving source self diagnosis accelerometer outline structural diagram of inventive embodiments in Fig. 4；

It (310) is the embedded driving source self diagnosis accelerometer sealing cap of this patent；

It (320) is the ceramic package shell of this patent；

It (330) is the embedded driving source self diagnosis accelerometer sensitive chip of this patent；

(340) chip is handled for the interface of the embedded driving source self diagnosis accelerometer of this patent；

It (350) is the embedded piezoelectric vibration generator system of this patent；

(351) positive electrode is driven for the embedded piezoelectric vibration generator system of this patent；

(352) negative electrode is driven for the embedded piezoelectric vibration generator system of this patent；

(351a), (351b), (351c) ... (351j) be driving positive electrode lamination exit；

(352a), (352b), (352c) ... (352j) be driving negative electrode array be layered exit.

Fig. 5 is the embedded piezoelectric vibration generator system electrode schematic diagram of the utility model embodiment.

The embedded driving source self diagnosis accelerometer uses all solid state low-temperature co-fired ceramics (LTCC, Low Temperature Co-fired Ceramic) substrate and embedded piezoelectric vibration generator system, sensitive chip and interface handles chip The method that integral system encapsulates (SIP, System in a package), the process of encapsulation are as shown in Figure 4；

Step 1: the good micro-acceleration gauge sensitive chip (330) of scribing is accurately fixed on using adhesive low temperature co-fired On the embedded piezoelectric vibration generator system (350) of ceramic package shell (320) substrate.

Step 2: micro-acceleration gauge interface, which is handled the electrode on chip (340), using metal lead wire guides to embedded vibration The surface drive electrode of dynamic platform (350) is to upper (351,352).

Step 3: package casing is sealed using sealing cap (310) after completing the electrical connection in encapsulation.

The embedded piezoelectric vibration generator system electrode structure of this patent is as shown in Figure 4.

Using the axially vertical direction definition of embedded piezoelectric vibration generator system as Z axis, the horizontal direction vertical with Z axis is defined as definition X-axis, the direction definition vertical with the plane that X-axis and Z axis form are Y-axis.

Driving positive electrode (351) be by Piezoelectric Driving positive electrode lamination exit (351a), (351b), (351c) ... (351j) is distributed across Z axis axial direction connection positive electrode with lamination planar structure and forms.

Driving negative electrode (352) is to be layered exit by Piezoelectric Driving negative electrode array with the friendship of metal throuth hole array structure Fork is distributed and axially connects formation along Z axis.

The manufacturing method of embedded piezoelectric vibration generator system, its step are as follows:

Step A: by PZT, PMnN and PMgN piezoceramic material according to weight ratio 0.92:0.05:0.03 mixed grinding And drying is granulated, vegetation obtains PZT-PMnN-PMgN piezoceramic material powder；

Step B: added in the PZT-PMnN-PMgN piezoceramic material powder being prepared in step: 85% it is molten The weight ratio of agent, the dispersing agent of 1.5%-2%, the adhesive and plasticizer of 3%-4%, plasticizer and adhesive is 0.4: 1；And ceramic diaphragm is prepared by casting technique, ceramic diaphragm with a thickness of 0.05-0.1mm；

Step C: using silver-colored palladium electrode material, wherein the weight ratio of metallic silver and palladium is 7:3, prepares silver-colored palladium electrode slurry, The PZT-PMnN-PMgN piezoceramic material powder prepared in the step A of 0.3%-0.5% is added in silver-colored palladium electrode slurry, By being uniformly mixing to obtain electrode material；

Step D: it uses puncher and is punched for the ceramic diaphragm being prepared in step B, by printing machine in ceramic diaphragm The electrode material being prepared in upper print steps C, then by lamination, etc. static pressure, dumping, sintering, by silver block and reflux Welding procedure completes piezoelectric vibration generator system.

Not more than 920 DEG C of sintering temperature in sintering process in the step D.

Step E: the polarization process stage is drawn electrode group by polarization clamp using oil bath polarization method simultaneously, polarized electric field For 3Kv/mm-6Kv/mm, poling temperature is 100 DEG C -150 DEG C, polarization time 20min-50min.

The solvent is the mixture for having dimethylbenzene and n-butanol to mix, mixed proportion 7:3.

Described adhesive is polyvinyl butyral.

The plasticizer is neck dibatyl phithalate.

Each embodiment in this specification is described in a progressive manner, the highlights of each of the examples are with other The difference of embodiment, the same or similar parts in each embodiment may refer to each other.

Specific case used herein is expounded the principles of the present invention and embodiment, above embodiments Explanation be merely used to help understand the method and its core concept of the utility model；Meanwhile for the general technology of this field Personnel, based on the idea of the present invention, there will be changes in the specific implementation manner and application range.In conclusion The content of the present specification should not be construed as a limitation of the present invention.

Claims (10)

1. a kind of piezoelectric vibration motivates self diagnosis mems accelerometer watch core, which is characterized in that the accelerometer watch core includes: Top crown, middle plate, bottom crown and shake table, the middle plate are located at the top crown and the bottom crown middle, The middle plate is connected to fixed position by an overarm, and the top crown and the middle plate constitute first capacitor, The bottom crown and the middle plate constitute the second capacitor, and the first capacitor and second capacitor constitute a pair of of differential electrical Hold；The shake table includes feedback layer and vibration level, and the feedback layer is located on the downside of the bottom crown, and the vibration level is located at institute It states on the downside of feedback layer；The feedback layer surface draws feedback output positive electrode and feedback output negative electrode, the vibration layer surface Draw driving positive electrode and driving negative electrode.

2. piezoelectric vibration according to claim 1 motivates self diagnosis mems accelerometer watch core, which is characterized in that described anti- Feedback layer and the vibration level are all made of the preparation of low-temperature co-fired ceramics technique.

3. piezoelectric vibration according to claim 1 motivates self diagnosis mems accelerometer watch core, which is characterized in that on described The equal length of pole plate, the middle plate and the bottom crown.

4. piezoelectric vibration according to claim 1 motivates self diagnosis mems accelerometer watch core, which is characterized in that on described Pole plate, the middle plate and the bottom crown are arranged in parallel.

5. piezoelectric vibration according to claim 1 motivates self diagnosis mems accelerometer watch core, which is characterized in that on described Pole plate and middle plate face setting, the bottom crown and middle plate face setting, the top crown and described The setting of bottom crown face.

6. a kind of motivate self diagnosis mems accelerometer watch core applied to piezoelectric vibration described in claim 1-5 any one Accelerometer, which is characterized in that the accelerometer includes: watch core, charge amplifier circuit, charge transport circuit, charge product Point device circuit and shake table closed-loop driving circuit, the output end of the watch core middle plate are defeated with the charge amplifier circuit Enter end connection, the output end of the charge amplifier circuit is connect with the input terminal of the charge transport circuit, the charge fortune The output end on transmission of electricity road is connect with the input terminal of the charge integrator circuits, the watch core, the charge amplifier circuit, institute It states charge transport circuit and the charge integrator circuits constitutes negative feedback loop；The shake table part of the watch core and the vibration Dynamic platform closed-loop driving circuit connection.

7. accelerometer according to claim 6, which is characterized in that the charge amplifier circuit includes: clock, first Charge amplifier and third capacitor, the clock include the first clock pins and second clock pin, the first charge amplification The anode of device is connect with the second clock pin, and the cathode of first charge amplifier and first clock pins connect It connects, the capacitor is connected in parallel with first charge amplifier, first clock pins and first charge amplifier Output end connection.

8. accelerometer according to claim 6, which is characterized in that the charge transport circuit include: the 4th capacitor and Clock, the clock include the first clock pins and second clock pin, and the input terminal and output end of the 4th capacitor are distinguished It is connect with first clock pins and the second clock pin.

9. accelerometer according to claim 8, which is characterized in that the charge integrator circuits include: the first charge Integrator and the 5th capacitor, first clock pins are connect with the cathode of first charge integrator, first charge The plus earth of integrator, first charge integrator are connected in parallel with the 5th capacitor.

10. accelerometer according to claim 6, which is characterized in that the shake table closed-loop driving circuit includes: second Gain amplifier, subtracter, multiplier, the second charge integrator, variable gain amplifier and voltage controlled oscillator；External reference electricity The input terminal on road is connect with the input terminal of the subtracter and the voltage controlled oscillator input terminal respectively, the voltage controlled oscillator Output end is connect with the input terminal of the multiplier, the output end of the subtracter respectively with second charge integration amplifier Output end connection, the plus earth of second charge integration amplifier, the cathode of second charge integration amplifier with The vibration level connection, the output end of second gain amplifier are connect with the vibration level, second gain amplifier Anode connect with the multiplier, the cathode of second gain amplifier is grounded.