CN205305058U - Microphone circuit board and mems microphone - Google Patents

Abstract

The utility model relates to a microphone circuit board and a MEMS microphone. This microphone circuit board includes: the base plate, the cavity has in the base plate, the cavity includes three rectangle lateral wall, two waist lateral walls and a topside lateral wall, the metal level, the metal level covers on the upper surface and/or lower surface of base plate, the metal level extends to on the rectangle lateral wall and topside lateral wall of cavity. The utility model discloses a technical problem that will solve reduces the electromagnetic interference of external electromagnetic wave to setting up the electron device in the cavity.

Description

Microphone circuit plate and MEMS microphone

Technical field

This utility model belongs to technical field of electronic products, and specifically, this utility model relates to a kind of microphone circuit plate and a kind of MEMS microphone.

Background technology

Mike is as the important component part that acoustic-electrical transducer part is electronic product, and along with the correlation technique of electronic product is fast-developing, the application of mike is very extensive. Wherein, MEMS microphone is to apply maximum mike devices in the electronic product such as mobile phone, panel computer at present. Owing to the mike in electronic product is proposed higher performance requirement by consumer, those skilled in the art are updating acoustical behavior and the stability of MEMS microphone.

Owing to the electronic product such as mobile phone, panel computer having the circuit of multiple electromagnetic device and complexity, so the electromagnetic environment of complexity can be formed in electronic product. And MEMS microphone is more sensitive electronic device, if subjected to the interference of external electromagnetic field, then the acoustic-electric energy transform performance cannot brought into normal play, thus reducing the call of user, recording quality. When being subject to serious electromagnetic interference, MEMS microphone likely produces the performance damage that cannot recover.

Thus, it is necessary to the structure of MEMS microphone is improved, reduce its electromagnetic interference being subject in electronic product, to provide good acoustic-electric transducing effect.

Utility model content

A purpose of the present utility model is to provide shielding protection for the device in mike.

According to an aspect of the present utility model, it is provided that a kind of microphone circuit plate, including:

Substrate, has cavity in described substrate, described cavity includes three rectangular side wall, two waist sidewalls and a top margin sidewall;

Metal level, described metal level covers on upper surface and/or the lower surface of described substrate, and described metal level extends on rectangular side wall and the top margin sidewall of described cavity.

Alternatively, described metal level has wlding portion.

Alternatively, described metal level limits cabling district on the upper surface and/or following table of described substrate, is provided with lead-in wire via in described cabling district. Preferably, described metal level limits Liang Ge cabling district on the upper surface of described substrate, and described cabling district lays respectively at the outside of two described waist sidewalls, and two described cabling districts are separated by the metal level extended on described top margin sidewall.

More preferably, described metal level having two wlding portions, described wlding portion is disposed side by side between two described cabling districts.

More preferably, described wlding portion exposes described substrate.

Further, this utility model additionally provides a kind of MEMS microphone, including:

Upper plate, lower plate and above-mentioned microphone circuit plate, described microphone circuit plate is fixedly installed in described lower plate, and described upper plate is fixedly installed on described microphone circuit plate, and described cavity is formed with described upper plate, lower plate and holds chamber;

MEMS chip and asic chip, described MEMS chip and asic chip are arranged in described accommodation chamber.

One of the present utility model has technical effect that, extends to the metal level on the sidewall of described cavity and can form composition electro-magnetic screen layer on described sidewall, thus protection is likely to the electronic device being arranged in described cavity, reduces electromagnetic interference.

By referring to the accompanying drawing detailed description to exemplary embodiment of the present utility model, further feature of the present utility model and advantage thereof will be made apparent from.

Accompanying drawing explanation

The accompanying drawing of the part constituting description describes embodiment of the present utility model, and is used for together with the description explaining principle of the present utility model.

The top view of the microphone circuit plate that Fig. 1 this utility model specific embodiment provides.

Detailed description of the invention

Of the present utility model various exemplary embodiment is described in detail now with reference to accompanying drawing. It should also be noted that unless specifically stated otherwise, the parts otherwise set forth in these embodiments and positioned opposite, the numerical expression of step and numerical value are not intended to scope of the present utility model.

Description only actually at least one exemplary embodiment is illustrative below, never as any restriction to this utility model and application or use.

The technology and equipment that person of ordinary skill in the relevant is known is likely to be not discussed in detail, but in the appropriate case, described technology and equipment should be considered a part for description.

Shown here with in all examples discussed, any occurrence should be construed as merely exemplary, not as restriction. Therefore, other example of exemplary embodiment can have different values.

It should also be noted that similar label and letter below figure represent similar terms, therefore, once a certain Xiang Yi accompanying drawing is defined, then it need not be further discussed in accompanying drawing subsequently.

This utility model provides a kind of microphone circuit plate, including substrate and metal level. This microphone circuit plate is usually used as the la m of MEMS microphone structure, for forming the accommodation chamber holding MEMS chip, so, described substrate has cavity. Described metal level covers on the surface of described substrate, for instance, it is possible to cover on an upper, it is also possible to cover on the lower surface. Preferably, the upper and lower surface of described substrate is covered with metal level. Especially, described metal level should extend to the sidewall of described cavity from the upper and lower surface of described substrate. When described microphone circuit plate is as the la m of MEMS microphone, described metal level answers ground connection, to form shield effectiveness. Owing to described metal level extends on the sidewall of described cavity, thus it is possible to low potential layer is enclosed in formation one around described cavity, thus forming effectiveness, the electromagnetic wave in the minimizing external world, electromagnetic field enter in described cavity from the direction of described sidewall.

The shape of described cavity is not limited by this utility model, and which sidewall that described metal level does not also specifically extend to cavity limits. Generally, each part of sidewall, if able to extend to each sidewall of described cavity, is covered by described metal level, then can bring best effectiveness. Certainly, the factor such as those skilled in the art can require according to the actual performance of mike, shape of cavity, which sidewall that described metal level specifically extends to cavity selects, designs.

Specifically, as it is shown in figure 1, in a kind of embodiment of the present utility model, the shape of the cavity 11 of described substrate 1 is observed in the approximate rectangular combination of shapes with isosceles trapezoid from depression angle.Described cavity 11 includes 111, two waist sidewalls 112 of three rectangular side wall and a top margin sidewall 113. Described metal level 2 covers on the surface of described substrate 1; metal level 2 can extend directly on three described rectangular side wall 111 and described top margin sidewall 113; so; described metal level 2 can form complete shielding construction substantially around described cavity 11, to carry out electromagnetic shielding protection to cavity 11 is internal. Especially, if the upper and lower surface of described substrate 1 is all covered with metal level 2, then described metal level 2 can extend to the lower surface of described substrate 1 from the upper surface of described substrate 1 through described sidewall, and described sidewall is formed complete covering, the effectiveness of strengthening sidewall.

Further, described metal level 2 can limit cabling district 12 by hollow out on the upper surface of described substrate 1 and/or lower surface, and described cabling district 12 is for arranging the signal lead of mike. Described cabling district 12 can be provided with lead-in wire via 13, the through described substrate 1 of described lead-in wire via 13, the inwall of lead-in wire via 13 and end face can be covered with conductive layer 131. What described lead-in wire via 13 was signal lead arranges offer accommodation space. This utility model is not limiting as described metal level must surround the cabling district of which kind of shape, is also not intended on described substrate and to form how many cabling districts. Those skilled in the art can be designed according to practical situation.

Specifically, as it is shown in figure 1, in a kind of embodiment of the present utility model, described metal level 2 can limit Liang Ge cabling district 12 on described substrate 1, and described cabling district 12 lays respectively at the outside of two described waist sidewalls 112. In order to arrange lead-in wire via 13 in the two position, so, described metal level 2 does not directly extend to described waist sidewall 112 from the surface of substrate 1. Described metal level 2 can pass through rectangular side wall 111 and top margin sidewall 113 extends on described waist sidewall 112. Especially, outside described top margin sidewall 113, described metal level 2 by two described cabling districts 12 separately, and extends on described top margin sidewall 113. This structure of described metal level 2 better can provide electromagnetic shielding for the space in cavity 11.

Further, since described microphone circuit plate needs and other welding circuit boards, encapsulation when constituting mike, so, described microphone circuit plate needs to weld. In order to prevent welding material from flowing in other positions or the cavity 11 of substrate 1 in the molten state, the overall performance of mike is impacted, described metal level 2 can have wlding portion 21, and described wlding portion 21 is for limiting the position of wlding, it is prevented that wlding flow to other regions. Such as, as it is shown in figure 1, in a kind of embodiment of the present utility model, described metal level 2 can have two wlding portions 21, described wlding portion 21 is disposed side by side between two described cabling districts 12. When described microphone circuit plate is welded by needs, it is possible to wlding is set on described weld part, welds. Especially, described wlding portion 21 can be depression, it is also possible to be hollow out, and wlding can be limited in described wlding portion 21 by depression or hollow out. Preferably, described wlding portion 21 is hollow out, exposes the substrate 1 in this region. So, described substrate 1 can carry out more firm being welded and fixed with other circuit boards.

Further, this utility model additionally provides a kind of MEMS microphone, and this MEMS microphone includes: MEMS chip, asic chip, and upper plate, lower plate and above-mentioned microphone circuit plate.Described microphone circuit plate is fixedly installed in described lower plate, and described upper plate is then fixedly installed on described microphone circuit plate, and described cavity is formed with described upper plate, lower plate and holds chamber. Described MEMS chip and asic chip are arranged in described accommodation chamber. Wherein, described microphone circuit plate constitutes the sidewall sections of described MEMS microphone, owing to described metal level extends on the sidewall of described cavity, so, metal level can provide good effectiveness at the sidewall sections of MEMS microphone. It addition, described cabling district is also provided with holding wire, draw for the acoustical signal that MEMS microphone is collected.

Although specific embodiments more of the present utility model being described in detail already by example, but it should be appreciated by those skilled in the art, above example is merely to illustrate, rather than in order to limit scope of the present utility model. It should be appreciated by those skilled in the art, when without departing from scope and spirit of the present utility model, above example can be modified. Scope of the present utility model is defined by the following claims.

Claims (7)

1. a microphone circuit plate, it is characterised in that including:

Substrate (1), having cavity (11) in described substrate (1), described cavity (11) includes three rectangular side wall (111), two waist sidewalls (112) and a top margin sidewall (113);

Metal level (2), described metal level (2) covers on upper surface and/or the lower surface of described substrate (1), and described metal level (2) extends on rectangular side wall (111) and the top margin sidewall (113) of described cavity (11).

2. microphone circuit plate according to claim 1, it is characterised in that there is on described metal level (2) wlding portion (21).

3. microphone circuit plate according to claim 1, it is characterized in that, described metal level (2) limits cabling district (12) on the upper surface and/or following table of described substrate (1), is provided with lead-in wire via (13) in described cabling district (12).

4. microphone circuit plate according to claim 3, it is characterized in that, described metal level (2) limits Liang Ge cabling district (12) on the upper surface of described substrate (1), described cabling district (12) lays respectively at the outside of two described waist sidewalls (112), and two described cabling districts (12) are separated by the metal level (2) extended on described top margin sidewall (113).

5. microphone circuit plate according to claim 4, it is characterized in that, having two wlding portions (21) on described metal level (2), described wlding portion (21) is disposed side by side between two described cabling districts (12).

6. the microphone circuit plate according to claim 2 or 5, it is characterised in that described wlding portion (21) exposes described substrate (1).

7. a MEMS microphone, it is characterised in that including:

One of upper plate, lower plate and claim 1-6 are any described microphone circuit plate, described microphone circuit plate is fixedly installed in described lower plate, described upper plate is fixedly installed on described microphone circuit plate, and described cavity (11) is formed with described upper plate, lower plate and holds chamber;

MEMS chip and asic chip, described MEMS chip and asic chip are arranged in described accommodation chamber.