CN115567814A

CN115567814A - Microphone

Info

Publication number: CN115567814A
Application number: CN202211303583.6A
Authority: CN
Inventors: 刘占锋
Original assignee: Qingdao Goertek Intelligent Sensor Co Ltd
Current assignee: Qingdao Goertek Intelligent Sensor Co Ltd
Priority date: 2022-10-24
Filing date: 2022-10-24
Publication date: 2023-01-03

Abstract

The invention relates to the technical field of electroacoustic products, and discloses a microphone which comprises a substrate and a shell arranged on the substrate, wherein an ASIC (application specific integrated circuit) chip is arranged on the substrate, a heat dissipation structure is arranged in the substrate, the top end of the heat dissipation structure is in contact with the ASIC chip, the bottom end of the heat dissipation structure is arranged on the outer side of the substrate, and the coverage area of the heat dissipation structure is more than 50% of that of the ASIC chip. The heat generated by the ASIC chip in the invention can be conducted to the heat dissipation structure in real time, and then the heat dissipation structure conducts the heat to the outer side of the substrate in real time. Therefore, the invention can timely and efficiently conduct the heat generated by the ASIC chip to the external environment, avoid the back cavity air heating, reduce the thermal noise and improve the signal-to-noise ratio and the anti-electromagnetic radiation interference capability of the microphone.

Description

Microphone

Technical Field

The invention relates to the technical field of electroacoustic products, in particular to a microphone.

Background

The microphone comprises a substrate and a shell arranged on the substrate, wherein an ASIC chip and an MEMS chip are arranged on the substrate, and a sound hole is formed in the substrate corresponding to the MEMS chip. The ASIC chip is directly attached to the upper surface of the substrate, when the ASIC chip works normally or receives an RF signal, heat can be generated and cannot be conducted to the external environment in time, so that the air of a back cavity of the microphone generates thermal disturbance, thermal noise is generated, the noise reduction performance of the microphone is poor, and the signal-to-noise ratio performance and the anti-electromagnetic interference capacity of the microphone are reduced.

Disclosure of Invention

Aiming at the defects, the technical problems to be solved by the invention are as follows: the heat dissipation mechanism is in contact with the ASIC chip, so that heat generated by the ASIC chip is conducted to the external environment, thermal noise is reduced, and the signal-to-noise ratio and the anti-electromagnetic radiation interference capability of the microphone are improved.

In order to solve the technical problems, the technical scheme of the invention is as follows:

a microphone comprises a substrate and a shell arranged on the substrate, wherein an ASIC chip is arranged on the substrate, a heat dissipation structure is arranged in the substrate, the top end of the heat dissipation structure is in contact with the ASIC chip, the bottom end of the heat dissipation structure is arranged on the outer side of the substrate, and the coverage area of the heat dissipation structure is larger than 50% of that of the ASIC chip.

The preferred mode does, heat radiation structure includes many heat dissipation copper posts, every the top of heat dissipation copper post is all established the inboard surface of base plate, every the bottom of heat dissipation copper post is all established the outside surface of base plate.

Preferably, all the heat dissipation copper columns are arranged in an array.

The preferred mode is that all heat dissipation copper posts are arranged in uniform order.

Preferably, the coverage area of the heat dissipation structure is the coverage area of the ASIC chip.

The preferable mode is that copper plating layers are respectively arranged on the upper side and the lower side of the substrate, and each heat dissipation copper column is integrally structured with the copper plating layers on the two sides.

Preferably, the outer side of the copper plating layer on each side is exposed outside the insulating layer

Preferably, an MEMS chip is further disposed on the substrate, and the substrate corresponding to the MEMS chip is provided with a sound hole.

Preferably, the ASIC chip is electrically connected to the MEMS chip.

Preferably, the ASIC chip and the MEMS chip, and the ASIC chip and the substrate are electrically connected by gold wires, respectively.

After the technical scheme is adopted, the invention has the beneficial effects that:

the microphone comprises a substrate and a shell arranged on the substrate, wherein an ASIC chip is arranged on the substrate, a heat dissipation structure is arranged in the substrate, the top end of the heat dissipation structure is in contact with the ASIC chip, the bottom end of the heat dissipation structure is arranged on the outer side of the substrate, and the coverage area of the heat dissipation structure is larger than 50% of that of the ASIC chip. The heat generated by the operation of the ASIC chip can be conducted to the heat dissipation structure in real time, and then the heat dissipation structure is conducted to the outer side of the substrate in real time. Therefore, the invention can conduct the heat generated by the ASIC chip to the external environment in time and efficiently, so as to avoid back cavity air heating, reduce thermal noise, improve the signal-to-noise ratio and the anti-electromagnetic radiation interference capability of the microphone, and has simple structure and easy realization.

Because heat radiation structure includes many heat dissipation copper posts, the inside surface at the base plate is all established on the top of every heat dissipation copper post, and the outside surface at the base plate is all established to the bottom of every heat dissipation copper post, and this heat radiation structure has simple structure, easily manufacturing's advantage.

Because all the heat dissipation copper columns are arranged in an array manner, the heat conduction is uniform, and the heat dissipation efficiency is improved.

Because the coverage area of the heat dissipation structure is the coverage area of the ASIC chip, the heat conduction efficiency is improved by increasing the contact area.

Because the upper and lower both sides of base plate are provided with the copper facing respectively, every heat dissipation copper post all sets up with both sides copper facing body structure, and this mode of setting is convenient for manufacturing, is convenient for dispel the heat.

In conclusion, the invention solves the technical problems that the heat generated by the ASIC chip of the microphone in the prior art can not be dissipated in time, thereby causing thermal noise, reducing the signal-to-noise ratio of the microphone and the like; the invention arranges the heat radiation copper column on the substrate below the ASIC chip, directly and efficiently conducts heat to the external environment through the heat radiation copper column, reduces thermal noise, improves the signal-to-noise ratio and the anti-electromagnetic radiation interference capability of the microphone, and has simple structure and easy manufacture.

Drawings

FIG. 1 is a schematic diagram of a microphone according to the present invention;

in the figure: 1-substrate, 10-copper plating layer, 11-insulating layer, 2-shell, 3-ASIC chip, 4-MEMS chip, 5-heat dissipation structure, 50-heat dissipation copper column and 6-sound hole.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

As shown in figure 1, the microphone comprises a substrate 1 and a shell 2 arranged on the substrate 1, wherein an ASIC chip 3 and an MEMS chip 4 are arranged on the substrate 1, a sound hole 6 is formed on the substrate 1 corresponding to the MEMS chip 4, and the sound hole 6 is communicated with a back cavity of the MEMS chip 4.

The substrate 1 is a PCB, the shell 2 is welded on the substrate 1 through solder paste, and the ASIC chip 3 and the MEMS chip 4 are respectively glued on the substrate 1. The ASIC chip 3 is electrically connected to the MEMS chip 4, preferably, the ASIC chip 3 is electrically connected to the MEMS chip 4 by a gold wire, and the ASIC chip 3 is electrically connected to the substrate 1 by another gold wire.

As shown in fig. 1, in the present invention, a heat dissipation structure 5 is disposed in a substrate 1, a top end of the heat dissipation structure 5 is in contact with an ASIC chip 3, a bottom end of the heat dissipation structure 5 is disposed outside the substrate 1, and a coverage area of the heat dissipation structure 5 is greater than 50% of a coverage area of the ASIC chip 3, preferably, the coverage area of the heat dissipation structure 5 is the coverage area of the ASIC chip 3, and the coverage area is set to increase a heat conduction area and improve a heat conduction efficiency.

The heat that ASIC chip 3 work produced can conduct in real time to the heat radiation structure 5 rather than contacting, and heat radiation structure 5 conducts the outside to base plate 1 in real time again, and the heat that ASIC chip 3 produced can in time conduct to the external environment high-efficiently promptly, has avoided arousing the back of the body chamber air to generate heat, has reduced thermal noise, has improved the SNR and the anti-electromagnetic radiation interference ability of microphone.

As shown in fig. 1, the heat dissipation structure 5 includes a plurality of heat dissipation copper pillars 50, a top end of each heat dissipation copper pillar 50 is disposed on an inner surface of the substrate 1 and contacts with a lower surface of the ASIC chip 3 to conduct heat, and a bottom end of each heat dissipation copper pillar 50 is disposed on an outer surface of the substrate 1. In a preferred embodiment, all the heat-dissipating copper pillars 50 are arranged in an array. Of course, all the heat dissipation copper pillars 50 can also be arranged uniformly, and are not required to be arranged in an array, and the array heat dissipation copper pillars 50 are convenient to process and manufacture, and can uniformly conduct heat, thereby improving the heat dissipation efficiency.

As shown in fig. 1, copper plating layers 10 are respectively disposed on the upper and lower sides of a substrate 1, and each heat dissipation copper pillar 50 is integrally disposed with the copper plating layers 10 on the two sides, so that the integrated structure is convenient for manufacturing and reduces the manufacturing cost, and the heat dissipation structure 5 can uniformly conduct heat generated by the ASIC chip 3 by means of the copper plating layers 10, and can help heat conduction and improve heat conduction efficiency.

In the embodiment, an insulating layer 11 is arranged on the outer side of each copper-plated layer 10; and both ends of each heat dissipation copper pillar 50 are respectively exposed outside the insulating layer 11 of the corresponding side, thereby indirectly improving the heat dissipation efficiency.

Of course, the heat dissipation structure 5 is not limited to the heat dissipation copper pillar 50 listed above, and may be a heat dissipation structure such as a heat sink, a heat dissipation pillar, or a combination of a heat dissipation paste, as long as it can timely conduct heat generated by the ASIC chip 3 to the outside of the substrate 1.

The above description is only for the purpose of illustrating the preferred embodiments of the present invention and should not be taken as limiting the invention, and any modifications, equivalents and improvements made within the spirit and principles of the present invention should be included in the scope of the present invention.

Claims

1. A microphone comprises a substrate and a shell arranged on the substrate, wherein an ASIC chip is arranged on the substrate, and the microphone is characterized in that a heat dissipation structure is arranged in the substrate, the top end of the heat dissipation structure is in contact with the ASIC chip, the bottom end of the heat dissipation structure is arranged on the outer side of the substrate, and the coverage area of the heat dissipation structure is larger than 50% of the coverage area of the ASIC chip.

2. The microphone of claim 1, wherein the heat dissipation structure comprises a plurality of heat dissipation copper pillars, a top end of each heat dissipation copper pillar is disposed on an inner side surface of the substrate, and a bottom end of each heat dissipation copper pillar is disposed on an outer side surface of the substrate.

3. The microphone of claim 2, wherein all of the heat dissipating copper pillars are arranged in an array.

4. The microphone of claim 2, wherein all of the heat-dissipating copper pillars are arranged in a uniform array.

5. The microphone of claim 1, wherein a footprint of the heat dissipation structure is a footprint of the ASIC chip.

6. The microphone of claim 2, wherein copper plating layers are respectively disposed on the upper and lower sides of the substrate, and each of the heat-dissipating copper pillars is integrally formed with the copper plating layers on both sides.

7. The microphone of claim 6, wherein an insulating layer is provided on the outside of the copper plating layer on each side; and two ends of each heat dissipation copper column are respectively exposed outside the insulating layer on the corresponding side.

8. The microphone according to any one of claims 1 to 7, wherein a MEMS chip is further disposed on the substrate, and the substrate corresponding to the MEMS chip is provided with a sound hole.

9. The microphone of claim 8, wherein the ASIC chip is electrically connected with the MEMS chip.

10. The microphone according to claim 9, wherein the ASIC chip and the MEMS chip, and the ASIC chip and the substrate are electrically connected by gold wires, respectively.