CN104301850A

CN104301850A - Silicon microphone

Info

Publication number: CN104301850A
Application number: CN201410632724.8A
Authority: CN
Inventors: 侯杰
Original assignee: Shandong Gettop Acoustic Co Ltd
Current assignee: Shandong Gettop Acoustic Co Ltd
Priority date: 2014-11-11
Filing date: 2014-11-11
Publication date: 2015-01-21

Abstract

The invention discloses a silicon microphone, which comprises an MEMS (micro-electromechanical system) chip, a PCB (printed circuit board), a first shell mounted on the PCB and a second shell, wherein a shell cavity is formed in the second shell, and can be communicated with a chip cavity of the MEMS chip; the chip cavity and the shell cavity form a rear cavity. According to the silicon microphone, the rear cavity is formed by the chip cavity and the shell cavity, and the volume of the rear cavity of the silicon microphone is increased, so that a vibrating diaphragm of the silicon microphone can easily vibrate, and the sensitivity of the silicon microphone is improved.

Description

Silicon microphone

Technical field

The present invention relates to microphone techniques field, particularly a kind of silicon microphone.

Background technology

Along with socioeconomic development, the living standard of people is more and more higher, and microphone has been widely used in the devices such as cell phone, portable electronic device, digital camera and notebook computer in consumer field.Wherein silicon microphone is because compact size, stability are strong and can the feature of reflow soldering be widely used.

As shown in Figure 1, the housing 01 that traditional silicon microphone comprises MEMS chip 02, integrated circuit 06, pcb board 05 and covers at above pcb board 05, wherein MEMS chip 02 and integrated circuit 06 are installed on pcb board 05, and be all positioned at housing 01 inner chamber, housing 01 is provided with sound hole 04, housing 01 inner surface and pcb board 05, MEMS chip 02 outer surface and integrated circuit 06 outer surface form ante-chamber 03, form back cavity 07 between MEMS chip 02 inside and pcb board 05.

But, due to ante-chamber 03 to enter sound channel volume comparatively large, back cavity 07 only has MEMS chip 02 inner space part volume, causes the higher frequency of silicon microphone to respond too high, the sensitivity decrease of silicon microphone.

Therefore, how improving the sensitivity of silicon microphone, is those skilled in the art's technical problems urgently to be resolved hurrily.

Summary of the invention

The object of this invention is to provide a kind of silicon microphone, the sensitivity of this silicon microphone improves.

For achieving the above object, the invention provides a kind of silicon microphone, comprise MEMS chip, pcb board and be arranged on the first housing on described pcb board, it is characterized in that, also comprise the second housing, described second enclosure interior is provided with the shell cavity that can be communicated with the chip cavity of described MEMS chip, and described chip cavity and described shell cavity form back cavity.

Preferably, described second housing is fixed on described pcb board, and with the separate setting of described first housing.

Preferably, described pcb board inside is provided with the water conservancy diversion cavity being communicated with described chip cavity and described shell cavity.

Preferably, described first housing and described second housing all weld with described pcb board.

Preferably, described first housing is identical with the height of described second housing.

Preferably, described first housing and described second housing are integral type structure.

Preferably, a sidewall in described first housing and a sidewall in described second housing share.

Preferably, along the direction of transfer of sound, described chip cavity flaring.

In technique scheme, silicon microphone provided by the invention comprises MEMS chip, pcb board, is arranged on the first housing on pcb board and the second housing, second enclosure interior is provided with the shell cavity that can be communicated with the chip cavity of MEMS chip, and chip cavity and shell cavity form back cavity.

Known by foregoing description, in silicon microphone provided by the invention, because back cavity is formed by chip cavity and shell cavity, relative in above-mentioned background technology, the situation that back cavity only has chip cavity to form, the back cavity volume of the silicon microphone that the application provides increases, then the vibrating diaphragm of silicon microphone easily shakes, and the sensitivity of silicon microphone improves.

Accompanying drawing explanation

Fig. 1 is the structural representation of traditional silicon microphone;

The structural representation of the silicon microphone that Fig. 2 provides for the embodiment of the present invention.

Wherein in Fig. 1-2: 01-housing, 02-MEMS chip, 03-ante-chamber, 04-sound hole, 05-PCB plate, 06-integrated circuit, 07-back cavity;

1-first housing, 2-MEMS chip, 3-ante-chamber, 4-sound hole, 5-PCB plate, 6-integrated circuit, 7-chip cavity, 8-water conservancy diversion cavity, 9-second housing, 10-shell cavity, 11-welding plate.

Embodiment

Core of the present invention is to provide a kind of silicon microphone, and the sensitivity of this silicon microphone improves.

In order to make those skilled in the art understand technical scheme of the present invention better, below in conjunction with drawings and embodiments, the present invention is described in further detail.

Please refer to Fig. 2, in a kind of embodiment, silicon microphone provided by the invention comprises MEMS chip 2, pcb board 5, integrated circuit 6, is arranged on the first housing 1 and the second housing 9 above pcb board 5, wherein the second housing 9 can be arranged on the first housing 1, also can be arranged in juxtaposition with the first housing 1, be arranged on pcb board 5.Integrated circuit 6 English abbreviation is ASIC, and MEMS chip 2 is called sound transducer again in silicon microphone, is also called MEMS DIE.MEMS chip 2 and integrated circuit 6 are installed on pcb board 5, MEMS chip 2 is connected with integrated circuit 6, MEMS chip 2 and integrated circuit 6 are all positioned at the first housing 1, ante-chamber 3 is formed between first housing 1 inner surface and MEMS chip 2 outer surface and pcb board 5, second housing 9 inside is provided with shell cavity 10, chip cavity 7 and shell cavity 10 form back cavity, its chips cavity 7 and shell cavity 10 can pass through pipeline connection, preferably, pcb board 5 inside is provided with the water conservancy diversion cavity 8 being communicated with chip cavity 7 and shell cavity 10.Concrete, in order to avoid ante-chamber 3 and back cavity disturb mutually, the first housing 1 and the second housing 9 can be the housing of separate setting.First housing 1 is provided with sound hole 4, and sound hole 4 is specifically as follows one, concrete, and along the direction of transfer of sound at sound hole 4, MEMS chip 2 is positioned at immediately below sound hole 4.First housing 1 and the second housing 9 can all with pcb board 5 interference seal.

Operationally, outside sound enters ante-chamber 3 by sound hole 4 to silicon microphone, is delivered on the vibrating diaphragm of MEMS chip 2, makes diaphragm vibration, and produce the signal of telecommunication by wire, be delivered on integrated circuit 6, after chip process, audio signal exports from pcb board 5.

Known by foregoing description, in the silicon microphone that the specific embodiment of the invention provides, because back cavity is formed by chip cavity 7 and shell cavity 10, relative in above-mentioned background technology, the situation that back cavity only has chip cavity 7 to form, the back cavity volume of the silicon microphone that the application provides increases, then the vibrating diaphragm of silicon microphone easily shakes, the sensitivity of silicon microphone improves, and then improves the signal to noise ratio of silicon microphone.

For the ease of staff's processing and assembling silicon microphone, preferably, first housing 1 and the second housing 9 are integral type structure, and wherein the first housing 1 and the second housing 9 can share a sidewall, and namely a sidewall in the first housing 1 and a sidewall in the second housing 9 share.

In order to avoid external substance damages the first housing 1 and the second housing 9, preferably, the first housing 1 is identical with the height of the second housing 9.

In order to improve the sealing of the first housing 1 and the second housing 9 and pcb board 5, the first housing 1 and the second housing 9 all weld with pcb board 5.Because the first housing 1 and the second housing 9 all weld with pcb board 5, reduce the processing request of staff to the first housing 1, second housing 9 and pcb board 5.

Further, as shown in Figure 2, for the ease of sound transmission, preferably, along the direction of transfer of sound, chip cavity 7 flaring.

In this specification, each embodiment adopts the mode of going forward one by one to describe, and what each embodiment stressed is the difference with other embodiments, between each embodiment identical similar portion mutually see.

To the above-mentioned explanation of the disclosed embodiments, professional and technical personnel in the field are realized or uses the present invention.To be apparent for those skilled in the art to the multiple amendment of these embodiments, General Principle as defined herein can without departing from the spirit or scope of the present invention, realize in other embodiments.Therefore, the present invention can not be restricted to these embodiments shown in this article, but will meet the widest scope consistent with principle disclosed herein and features of novelty.

Claims

1. a silicon microphone, the first housing (1) comprising MEMS chip (2), pcb board (5) and be arranged on described pcb board (5), it is characterized in that, also comprise the second housing (9), described second housing (9) inside is provided with the shell cavity (10) that can be communicated with the chip cavity (7) of described MEMS chip (2), and described chip cavity (7) and described shell cavity (10) form back cavity.

2. silicon microphone according to claim 1, is characterized in that, described second housing (9) is fixed on described pcb board (5), and with the separate setting of described first housing (1).

3. silicon microphone according to claim 2, is characterized in that, described pcb board (5) inside is provided with the water conservancy diversion cavity (8) being communicated with described chip cavity (7) and described shell cavity (10).

4. silicon microphone according to claim 2, is characterized in that, described first housing (1) and described second housing (9) all weld with described pcb board (5).

5. silicon microphone according to claim 2, is characterized in that, described first housing (1) is identical with the height of described second housing (9).

6. silicon microphone according to claim 1, is characterized in that, described first housing (1) and described second housing (9) are integral type structure.

7. silicon microphone according to claim 6, is characterized in that, a sidewall in described first housing (1) and a sidewall in described second housing (9) share.

8. the silicon microphone according to any one of claim 1-7, is characterized in that, along the direction of transfer of sound, and described chip cavity (7) flaring.