CN211240080U

CN211240080U - MEMS vibration sensor

Info

Publication number: CN211240080U
Application number: CN201921693268.2U
Authority: CN
Inventors: 罗旭辉
Original assignee: Sichuan Ruihao Microelectronics Technology Co ltd
Current assignee: Sichuan Ruihao Microelectronics Technology Co ltd
Priority date: 2019-10-10
Filing date: 2019-10-10
Publication date: 2020-08-11
Anticipated expiration: 2029-10-10

Abstract

The utility model discloses a MEMS vibration sensor, which comprises a PCB and a first shell, wherein the PCB and the first shell enclose a containing space, the first shell is provided with a sound inlet, and an MEMS chip and an ASIC chip which are arranged on the PCB are arranged in the containing space; the second shell covers the first shell, a vibration space is formed between the second shell and the first shell, and the sound inlet is communicated with the accommodating space and the vibration space; be equipped with the vibration unit who fixes in second casing bottom in the vibration space, the vibration unit includes: the stretching film ring is fixed at the bottom of the second shell, the vibrating film is arranged on the stretching film ring in a tensioning mode, and the vibrator is arranged on the vibrating film. The MEMS vibration sensor of the utility model can pick up vibration signals and convert the vibration signals into electric signals, thereby being used as a bone conduction microphone; and PCB and second casing adopt full seal structure, possess high level waterproof, dampproofing, dustproof performance.

Description

MEMS vibration sensor

Technical Field

The utility model relates to a sensor technical field, concretely relates to MEMS vibration sensor.

Background

A silicon microphone, i.e., an MEMS (micro electro mechanical Systems) microphone, is an electroacoustic transducer fabricated by micromachining technology, and has the characteristics of small volume, good frequency response, low noise, and the like.

The conventional silicon microphone mainly includes: a housing and a PCB (printed Circuit board), a MEMS chip and an ASIC (Application Specific Integrated Circuit) chip attached to the PCB inside the housing; the MEMS chip, the ASIC chip and the PCB are connected through gold wires to realize electric communication, and sound signals enter the shell through the sound inlet hole in the shell and are transmitted to the vibrating diaphragm of the MEMS chip, so that the vibrating diaphragm acts to realize acoustoelectric conversion.

Conventional silicon microphones can pick up sound signals that propagate through the air.

SUMMERY OF THE UTILITY MODEL

An object of the utility model is to provide a MEMS vibration sensor based on traditional MEMS microphone realizes the extraction to vibration signal.

The technical scheme is as follows: an MEMS vibration sensor comprises a PCB and a first shell arranged on the PCB, wherein the PCB and the first shell enclose a containing space, the first shell is provided with a sound inlet, and an MEMS chip and an ASIC chip which are arranged on the PCB are arranged in the containing space; the PCB is characterized by further comprising a second shell arranged on the PCB, the second shell covers the first shell, a vibration space is formed between the second shell and the first shell, and the sound inlet hole is communicated with the accommodating space and the vibration space; be equipped with in the vibration space and fix the vibration unit of second casing bottom, the vibration unit includes: the film stretching ring is fixed at the bottom of the second shell, the vibrating film is arranged on the film stretching ring in a tensioning mode, and the vibrator is arranged on the vibrating film.

According to the technical solution provided by the utility model, the embodiment of the utility model has the following advantage:

this MEMS vibration sensor constitutes vibration space between two-layer shell through addding the second shell to at the inside vibration unit that increases in vibration space, then, when this MEMS vibration sensor receives external force vibration, the oscillator of vibration unit can present synchronous vibration because of accepting vibration signal on the vibrating diaphragm, and then the vibrating diaphragm of vibration unit can promote the air vibration in vibration space and the accommodation space, make the MEMS chip can detect air vibration and change into the signal of telecommunication, thereby realized converting vibration signal into the signal of telecommunication.

The MEMS vibration sensor with the structure can pick up vibration signals conducted by solids and convert the vibration signals into electric signals, so that the MEMS vibration sensor can be used as a bone conduction microphone and is used for bone conduction transmission of a human body.

Furthermore, because PCB and second casing adopt full seal structure, work under the full seal condition, possess high level waterproof, dampproofing, dustproof performance.

Drawings

In order to more clearly illustrate the technical solution of the embodiment of the present invention, the drawings used in the description of the embodiment will be briefly introduced below.

Fig. 1 is a schematic cross-sectional structural diagram of a MEMS vibration sensor provided by the present invention.

Detailed Description

In order to make the technical solution of the present invention better understood, the technical solution of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings in the embodiments of the present invention, and it is obvious that the described embodiments are only some embodiments of the present invention, not all embodiments. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative efforts shall belong to the protection scope of the present invention.

The following is a detailed description of specific embodiments.

Referring to fig. 1, an embodiment of the present invention provides a MEMS vibration sensor (sensor for short). The MEMS vibration sensor is a silicon microphone body, the silicon microphone body comprises a PCB1 and a first shell 2 arranged on a PCB1, the PCB1 and the first shell 2 enclose a containing space, and a MEMS chip 3 and an ASIC chip 4 which are arranged (for example, mounted) on the PCB1 are arranged in the containing space; the MEMS chip 3 and the ASIC chip 4, and the ASIC chip 4 and the PCB1 can be connected through gold wires; the first shell 2 is provided with a sound inlet 5. The silicon microphone body is a complete microphone for converting sound signals propagated through the air into electrical signals.

Specifically, the MEMS vibration sensor of the present embodiment further includes a second case 6 disposed on the PCB1, the second case 6 encloses the first case 2, a vibration space is formed between the second case 6 and the first case 2, and the sound inlet 5 communicates the accommodating space and the vibration space.

Still be equipped with in the vibration space and fix the vibration unit of second casing 10 bottom, the vibration unit includes: a film stretching ring 9 fixed at the bottom of the second shell 10-2, a vibrating film 8 arranged on the film stretching ring 9 in a tensioning way, and a vibrator 7 arranged on the vibrating film 8.

Optionally, the diaphragm 8 is disposed on a side of the film stretching ring 9 facing the first housing 2, and the vibrator 7 is disposed on a side of the diaphragm 8 facing the first housing 2.

Optionally, the thickness of the vibrator 7 is smaller than that of the film stretching ring 9.

Optionally, the vibrator 7 is a metal vibrator, the metal vibrator may be a square or rectangular or circular or polygonal metal block, and the metal vibrator may be made of stainless steel, copper or other materials.

Based on the vibrating unit, when the sensor receives external force vibration, oscillator 7 can present synchronous vibration because of accepting the signal on vibrating diaphragm 8, and vibrating diaphragm 8 can compress/promote the air vibration in the vibration space, and then makes the air vibration in the accommodation space through sound inlet 5, and the pressure of air vibration acts on MEMS chip 3, and MEMS chip 3 converts vibration energy into the signal of telecommunication. Thereby achieving the pickup of the vibration signal.

In order to transmit the vibration signal and reduce the noise signal interference, it is preferable that the second casing 10 is a fully enclosed casing, and the sensor operates under a fully sealed condition.

The totally-enclosed working environment has low requirements on the working environment, the influence of water vapor, moisture, dust and the like on the product is less, and high-level waterproof, moistureproof and dustproof performances can be realized.

The totally closed working environment can also reduce noise interference, especially low-frequency interference,

the above embodiments are only used to illustrate the technical solution of the present invention, and not to limit it; those of ordinary skill in the art will understand that: the technical solutions described in the above embodiments may still be modified, or some technical features may be equivalently replaced; such modifications and substitutions do not depart from the spirit and scope of the present invention in its corresponding aspects.

Claims

1. A MEMS vibration sensor comprises a silicon microphone body, wherein the silicon microphone body comprises a PCB and a first shell arranged on the PCB, the PCB and the first shell form an accommodating space in a surrounding mode, the first shell is provided with a sound inlet, and an MEMS chip and an ASIC chip which are arranged on the PCB are arranged in the accommodating space; it is characterized in that the preparation method is characterized in that,

the PCB is provided with a first shell, the PCB is provided with a sound inlet hole, the PCB is provided with a second shell, the second shell is arranged on the PCB, the second shell is a totally enclosed shell, the second shell covers the first shell, a vibration space is formed between the second shell and the first shell, and the sound inlet hole is communicated with the accommodating space and the vibration space;

be equipped with in the vibration space and fix the vibration unit of second casing bottom, the vibration unit includes: the film stretching ring is fixed at the bottom of the second shell, the vibrating film is arranged on the film stretching ring in a tensioning mode, and the vibrator is arranged on the vibrating film.

2. The MEMS vibration sensor of claim 1,

the vibrating membrane is arranged on one side of the membrane stretching ring facing the first shell, and the vibrator is arranged on one surface of the vibrating membrane, which is far away from the first shell.

3. The MEMS vibration sensor of claim 1,

the thickness of the vibrator is smaller than that of the film stretching ring.

4. The MEMS vibration sensor of claim 1,

the oscillator is a metal block with a square shape, a rectangular shape, a circular shape or a polygonal shape.