CN207427481U - A kind of microphone test device - Google Patents
A kind of microphone test device Download PDFInfo
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- CN207427481U CN207427481U CN201721312025.0U CN201721312025U CN207427481U CN 207427481 U CN207427481 U CN 207427481U CN 201721312025 U CN201721312025 U CN 201721312025U CN 207427481 U CN207427481 U CN 207427481U
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Abstract
The utility model discloses a kind of microphone test device, including test probe, power amplifier module, audio playing module and power module.Wherein, the test probe is electrically connected on microphone to be measured, and audio input signal is converted to the electric signal to be formed for gathering microphone to be measured, the electric signal is sent to the power amplifier module.The test probe and the audio playing module is electrically connected in the power amplifier module, for amplifying the power of the electric signal, and the electric signal is sent to the audio playing module.The audio playing module is used to the electric signal being converted to audio output signal, and plays the audio output signal.The power module is used to provide power supply for the microphone test device.The microphone test device is realized quick detection microphone, has been reduced or remitted the step of tearing machine testing open, saved detection time and human resources by said structure.
Description
Technical field
The utility model is related to mobile electronic device fields, more particularly to a kind of microphone test device.
Background technology
In order to promote prouctiveness, in the production process of mobile electronic device, by surface mounting technology (Surface
Mount Technology, SMT) PCBA mainboards after processing generally without audio-frequency test, during being mounted, hold
Easily occur to go wrong due to patch or welding, the microphone of mobile electronic device is caused to break down, so that defective products
General assembly flow is flow to, microphone is detected at this time and the mobile electron, it is necessary to completing assembling is carried out maintenance to defective products
Equipment carries out tearing machine open, treats to ressemble the component of mobile electronic device after microphone repair again, this process consumes not
Few time and human resources cause detection efficiency low.
Utility model content
In view of the deficiencies in the prior art, the utility model provides a kind of microphone test device, improves detection efficiency,
Save time and human resources.
To achieve these goals, the utility model takes following technical solution：
The utility model provides a kind of microphone test device, is played including test probe, power amplifier module, audio
Module and power module, wherein, the test probe is electrically connected on microphone to be measured, for gathering microphone to be measured by sound
Frequency input signal converts the electric signal to be formed, and the electric signal is sent to the power amplifier module；The power amplification mould
The test probe and the audio playing module is electrically connected in block, for amplifying the power of the electric signal, and by institute
It states electric signal and is sent to the audio playing module；The audio playing module is used to the electric signal being converted to audio output
Signal, and play the audio output signal；The power module is used to provide power supply for the microphone test device.
Preferably, the microphone test device further includes filter module, and the filter module is electrically connected at the survey
Between probe header and power amplifier module, the electric signal for the test probe to be gathered is filtered, and will be passed through
Electric signal after filtering process is sent at the power amplifier module.
Preferably, the audio playing module includes loud speaker, earphone and plays switching switch, the broadcasting switching switch
For the loud speaker and earphone to be selected an electrical communication to the power amplifier module.
Preferably, the power module includes external power interface, built-in power and power change-over switch, the external electricity
Source interface is electrically connected to the power amplifier module, and the built-in power is connected to the power by power change-over switch and puts
Big module, the power change-over switch are used for when the external power interface does not connect with external power supply, the power supply switching
Switch connects the built-in power and the power amplifier module by being closed.
Preferably, the external power interface external direct current power supply, the built-in power are DC power supply.
Preferably, the power amplifier module includes power amplifier chip, and the power amplifier chip includes reversely input
Pin, positive input pin, shut-off pin, bypass pin, reversed output pin, positive output pin, energization pins and ground connection
Pin, the reversed input pin passes sequentially through the first capacitor C1 and first resistor R1 is connected on the filter module, and
It passes sequentially through second resistance R2 and 3rd resistor R3 and is connected in series to the reversed output pin, the forward direction input pin and the side
Pass foot is grounded by the second capacitor C2, and the shut-off pin ground connection, the reversed output pin is opened with the broadcasting switching
Series connection is closed, the forward direction output pin is connected on the positive terminal of the loud speaker, the energization pins and the power supply mould
Block is connected, and passes through series connection the 3rd capacitor C3 ground connection, the grounding pin ground connection.
Preferably, the broadcasting switching switch is connected in series to the negative terminals of the loud speaker, and passes through the 4th resistance R4
Respectively with the L channel circuit of the earphone and the right channel circuit connected in series of the earphone, the L channel circuit of the earphone and institute
It is parallel with one another to state the right channel circuit of earphone, and is grounded together.
Preferably, the external power interface is parallel on the access between the energization pins and the 3rd capacitor C3,
One end of the power change-over switch is parallel to by the 5th resistance R5 between the external power interface and the energization pins
Access on, the other end is connected to the supply voltage interface of built-in power, and the power change-over switch connects with the external power supply
Between mouth node in parallel and the access of the energization pins, the 4th capacitor C4 of ground connection and the be grounded the 5th are parallel with respectively
Capacitor C5.
Preferably, the test probe includes the first thimble and the second thimble, and first thimble is to be measured for being connected to
Access where the anode of microphone, second thimble are used for access where being connected to the cathode of microphone to be measured.
Preferably, the filter module includes the first inductor L1 and the second inductor L2, the first inductor L1's
One end is connected to second thimble, and ground connection is parallel between the first inductor L1 and the access of second thimble connection
The 6th capacitor C6, the other end of the first inductor L1 is directly grounded, while the other end of the first inductor L1
Pass sequentially through the 6th resistance R6 and the 7th resistance R7 ground connection；One end of the second inductor L2 is connected to first thimble,
It is parallel with the 7th capacitor C7 of ground connection between the second inductor L2 and the access of first thimble connection, described second
The other end of inductor L2 passes sequentially through first resistor R1 and the first capacitor C1 is connected to the reversed input pin, simultaneously
The other end of the second inductor L2 pass sequentially through the 8th resistance R8, the 9th resistance R9 and the tenth resistance R10 be connected to it is described
On access between external power interface and the energization pins, the filter module further includes the 8th capacitor C8, and described
One end of eight capacitor C8 is connected between the 6th resistance R6 and the 7th resistance R7, and the other end is connected to the 8th resistance
Between R8 and the 9th resistance R9.
A kind of microphone test device provided by the utility model, by the way that the test probe is electrically connected to wheat to be measured
On gram wind, after the microphone to be measured receives the audio input signal of sound source, played according to the audio of microphone test device
Module whether can normal sounding, realization quickly judges whether the microphone to be measured normal, microphone test device operation
It is convenient, detection efficiency is improved, saves time and human resources.
Description of the drawings
Fig. 1 is the structure diagram for the microphone test device that the utility model embodiment provides；
Fig. 2 is the circuit diagram for the microphone test device that the utility model embodiment provides.
Specific embodiment
To make the purpose of this utility model, technical solution and advantage clearer, below in conjunction with the accompanying drawings to the utility model
Specific embodiment be described in detail.The example of these preferred embodiments is illustrated in the accompanying drawings.Institute in attached drawing
Show what is be merely exemplary with the embodiment of the utility model described with reference to the accompanying drawings, and the utility model is not limited to this
A little embodiments.
Here, it should also be noted that, in order to avoid because having obscured the utility model during unnecessary details, in the accompanying drawings
The structure and/or processing step closely related with scheme according to the present utility model are illustrate only, and is omitted and this practicality
The little other details of new relationship.
Shown referring to Figures 1 and 2, the utility model embodiment provides a kind of microphone test device, is visited including test
First 1, power amplifier module 2, audio playing module 3 and power module 4.
Wherein, the test probe 1 is electrically connected on microphone to be measured, for gathering microphone to be measured by audio input
Signal converts the electric signal to be formed, and the electric signal is sent to the power amplifier module 2.The power amplifier module 2 divides
The test probe 1 and the audio playing module 3 are not electrically connected, for amplifying the power of the electric signal, and by described in
Electric signal is sent to the audio playing module 3.The audio playing module 3 is used to the electric signal being converted to audio output
Signal, and play the audio output signal.The power module 4 is used to provide power supply for the microphone test device.
The microphone test device, can be by testing by the way that the test probe 1 is electrically connected on microphone to be measured
Personnel make the microphone to be measured receive the audio input signal of extraneous sound source, if described to modes such as microphone sounding to be measured
Microphone to be measured is normal, then audio input signal can be converted to electric signal and gathered by the test probe 1, through the power
After amplification module 2 amplifies the electric signal, the electric signal is converted into audio output letter by the audio playing module 3
Number, i.e., whether tester can make a sound whether just to judge the microphone to be measured according to the audio playing module 3
Often.Test probe 1 need to only be connected on microphone to be measured and can be detected by the microphone test device, realize to Mike
The quick test of wind, saves detection time and human resources.
Further, the microphone test device further includes filter module 5, and the filter module 5 is electrically connected at institute
It states between test probe 1 and power amplifier module 52, the electric signal for the test probe 1 to be gathered is filtered,
And treated that electric signal is sent at the power amplifier module 2 by filtered.
The electric signal that the filter module 5 gathers the test probe 1 is filtered, and can be made in the electric signal
Noise signal remove, retaining needs the electric signal that detects so that tester can clearly hear the audio playing module 3
The output audio of broadcasting, to make accurate evaluation to microphone to be measured.
Further, the audio playing module 3 includes loud speaker 31, earphone 32 and plays switching switch 33, described
Switching switch 33 is played to be used to the loud speaker 31 and earphone 32 selecting an electrical communication to the power amplifier module 2.
In the present embodiment, by the broadcasting switching switch 33, the sound is selectively played by the loud speaker 31
Frequency output signal plays the audio output signal by the earphone 32, i.e. tester can be according to Site Detection environment
Demand, selection plays output audio with the more visible earphone 32 of output audio or using relatively convenient loud speaker 31.
Further, the power module 4 includes external power interface 41, built-in power 42 and power change-over switch
43, the external power interface 41 is electrically connected to the power amplifier module 2, and the built-in power 42 is opened by power supply switching
Close 43 and be connected to the power amplifier module 2, the power change-over switch 43 be used for when the external power interface 41 not with outside
During portion's power supply connection, the power change-over switch 43 connects the built-in power 42 and the power amplifier module by being closed
2。
In the present embodiment, the microphone test device can connect external power supply confession by the external power interface 41
Electricity, can be by being closed the power change-over switch 43, even when Site Detection environment is inconvenient or progress outside is not allowed to connect electricity
Lead to the built-in power 42, powered by the built-in power 42 for the microphone detection device.
Specifically, 41 external direct current power supply of external power interface, the built-in power 42 are DC power supply.This implementation
In the range of the operating voltage for the microphone test device that example provides is preferably 2V-5.5V, usable charging adapter connects
Electricity, USB port power supply connect the modes such as external dc power, external dc power are linked into external power interface 41, for institute
State the power supply of microphone test device.
In the present embodiment, above-mentioned power amplifier module 2, audio playing module 3, power module 4 and filter module 5 be together
It is integrated on printed circuit board (PCB).
As shown in fig.2, the internal circuit configuration of the microphone test device is as follows：The power amplifier module
2 include power amplifier chip 21, and the power amplifier chip 21 includes reversed input pin (- IN pins), positive input pin
(+IN pins), shut-off pin (SHUTDOWN pins), bypass pin (BYPASS pins), (- OUT draws reversed output pin
Foot), positive output pin (+OUT pins), energization pins (VDO pins) and grounding pin (GND pin), the reversed input
Pin passes sequentially through the first capacitor C1 and first resistor R1 and is connected on the filter module 5, and passes sequentially through second resistance
R2 and 3rd resistor R3 is connected in series to the reversed output pin, the forward direction input pin and the bypass pin and passes through the second electricity
Container C2 is grounded, and the shut-off pin ground connection, the reversed output pin is connected with the broadcasting switching switch 33, the forward direction
Output pin is connected on the positive terminal of the loud speaker 31, and the energization pins are connected with the power module 4, and are passed through
The 3rd capacitor C3 that connects is grounded, the grounding pin ground connection.Illustratively, the resistance value of the first resistor R1 is 10K Ω, the
The resistance value of two resistance R2 is 22K Ω, and the resistance value of 3rd resistor R3 is that the capacitance of 2K Ω, the second capacitor C2 are 1 μ F.
Specifically, the broadcasting switching switch 33 is connected in series to the negative terminals of the loud speaker 31, and passes through the 4th electricity
It hinders right channel circuits 322 of the R4 respectively with the L channel circuit 321 of the earphone 32 and the earphone 32 to connect, the earphone 32
L channel circuit 321 and the earphone 32 right channel circuit 322 it is parallel with one another, and be grounded together.
Specifically, the external power interface 41 is parallel to the access between the energization pins and the 3rd capacitor C3
On, one end of the power change-over switch 43 is parallel to the external power interface 41 by the 5th resistance R5 and draws with the power supply
On access between foot, the other end is connected to the supply voltage interface (VBAT interfaces) of built-in power 42, and the power supply switching is opened
Between the access for closing 43 nodes and the energization pins in parallel with the external power interface 41, the of ground connection is parallel with respectively
Four capacitor C4 and the 5th capacitor C5 of ground connection.Illustratively, the resistance value of the 5th resistance R5 be 15K Ω, the described 4th
The capacitance that the capacitance of capacitor C4 is 10 μ F, the 5th capacitor C5 is 470 μ F.
Specifically, the test probe 1 includes the first thimble and the second thimble, and first thimble is to be measured for being connected to
Access where the anode of microphone, second thimble are used for access where being connected to the cathode of microphone to be measured.In this implementation
In example, where first thimble is connected to the anode of microphone to be measured on the inductance of access, tell that the second thimble is connected to wheat to be measured
Where the cathode of gram wind on the inductance of access.
Specifically, the filter module 5 includes the first inductor L1 and the second inductor L2, the first inductor L1's
One end is connected to second thimble, and ground connection is parallel between the first inductor L1 and the access of second thimble connection
The 6th capacitor C6, the other end of the first inductor L1 is directly grounded, while the other end of the first inductor L1
Pass sequentially through the 6th resistance R6 and the 7th resistance R7 ground connection；One end of the second inductor L2 is connected to first thimble,
It is parallel with the 7th capacitor C7 of ground connection between the second inductor L2 and the access of first thimble connection, described second
The other end of inductor L2 passes sequentially through first resistor R1 and the first capacitor C1 is connected to the reversed input pin, simultaneously
The other end of the second inductor L2 pass sequentially through the 8th resistance R8, the 9th resistance R9 and the tenth resistance R10 be connected to it is described
On access between external power interface 41 and the energization pins, the filter module 5 further includes the 8th capacitor C8, institute
The one end for stating the 8th capacitor C8 is connected between the 6th resistance R6 and the 7th resistance R7, and the other end is connected to the described 8th
Between resistance R8 and the 9th resistance R9.Illustratively, the resistance value of the 6th resistance R6 is 1.5K Ω, the 7th resistance R7's
Resistance value is that the resistance value of 10K Ω, the 8th resistance R8 are 1.5K Ω, and the resistance value of the 9th resistance R9 is 1K Ω, the described tenth
The resistance value of resistance R10 is that the inductance value of 7.5K Ω, the first inductor L1 and the second inductor L2 are 10uH, the described 6th
The capacitance of capacitor C6 and the 7th capacitor C7 are 0.1 μ F, and the capacitance of the 8th capacitor C8 is 4.7 μ F.
In the present embodiment, printed circuit board (PCB) is first made according to foregoing circuit figure, including by the power amplifier module 2,
Audio playing module 3, power module 4 and filter module 5 are integrated on printed circuit board (PCB), and test probe 1 is connected to filtering mould
Block 5, and corresponding wiring line connection is carried out, after printed circuit board (PCB) is made, shell is made using black appliances wood material, by the print
Printed circuit board is fitted into shell, exposes 1 probe 1 of test, the microphone test device is made.
In conclusion a kind of microphone test device that the utility model embodiment provides, by by the test probe 1
It is electrically connected on microphone to be measured, after the microphone to be measured receives the audio input signal of sound source, is surveyed according to microphone
The audio playing module 3 that trial assembly is put whether can normal sounding, realization quickly judge whether the microphone to be measured normal, the wheat
Gram wind test device is easy to operate, improves detection efficiency, saves time and human resources.
It should be noted that herein, relational terms such as first and second and the like are used merely to a reality
Body or operation are distinguished with another entity or operation, are deposited without necessarily requiring or implying between these entities or operation
In any this actual relation or order.Term " comprising ", "comprising" or its any other variant are intended to non-row
His property includes, so that process, method, article or equipment including a series of elements not only include those elements, and
And it further includes other elements that are not explicitly listed or further includes as this process, method, article or equipment institute inherently
Element.In the absence of more restrictions, the element limited by sentence "including a ...", it is not excluded that including institute
State in process, method, article or the equipment of element that also there are other identical elements.
The above is only the specific embodiment of the application, it is noted that for the ordinary skill people of the art
For member, on the premise of the application principle is not departed from, several improvements and modifications can also be made, for these changes and profit
Decorations, also should be regarded as the protection domain of the application.
Claims (10)
1. a kind of microphone test device, which is characterized in that played including test probe (1), power amplifier module (2), audio
Module (3) and power module (4), wherein,
The test probe (1) is electrically connected on microphone to be measured, turns audio input signal for gathering microphone to be measured
The electric signal to be formed is changed, the electric signal is sent to the power amplifier module (2)；
The test probe (1) and the audio playing module (3) is electrically connected in the power amplifier module (2), is used for
Amplify the power of the electric signal, and the electric signal is sent to the audio playing module (3)；
The audio playing module (3) is used to the electric signal being converted to audio output signal, and plays the audio output
Signal；
The power module (4) is used to provide power supply for the microphone test device.
2. microphone test device according to claim 1, which is characterized in that the microphone test device further includes filter
Ripple module (5), the filter module (5) are electrically connected between the test probe (1) and power amplifier module (2), are used for
The electric signal that the test probe (1) gathers is filtered, and treated that electric signal is sent to institute by filtered
It states at power amplifier module (2).
3. microphone test device according to claim 2, which is characterized in that the audio playing module (3) includes raising
Sound device (31), earphone (32) and broadcasting switching switch (33), the broadcasting switching switch (33) are used for the loud speaker (31)
An electrical communication is selected to the power amplifier module (2) with earphone (32).
4. microphone test device according to claim 3, which is characterized in that the power module (4) includes external electricity
Source interface (41), built-in power (42) and power change-over switch (43), the external power interface (41) are electrically connected to described
Power amplifier module (2), the built-in power (42) are connected to the power amplifier module by power change-over switch (43)
(2), the power change-over switch (43) is used for when the external power interface (41) does not connect with external power supply, the power supply
Switching switch (43) connects the built-in power (42) and the power amplifier module (2) by being closed.
5. microphone test device according to claim 4, which is characterized in that the external power interface (41) is external straight
Galvanic electricity source, the built-in power (42) are DC power supply.
6. microphone test device according to claim 4, which is characterized in that the power amplifier module (2) includes work(
Rate amplification chip (21), the power amplifier chip (21) include reversed input pin, positive input pin, shut-off pin, side
Pass foot, reversed output pin, positive output pin, energization pins and grounding pin, the reversed input pin pass sequentially through
First capacitor C1 and first resistor R1 is connected on the filter module (5), and passes sequentially through the electricity of second resistance R2 and the 3rd
Resistance R3 is connected in series to the reversed output pin, and the forward direction input pin and the bypass pin are connect by the second capacitor C2
Ground, the shut-off pin ground connection, the reversed output pin are connected with the broadcasting switching switch (33), and the positive output is drawn
Foot is connected on the positive terminal of the loud speaker (31), and the energization pins are connected with the power module (4), and pass through string
Join the 3rd capacitor C3 ground connection, the grounding pin ground connection.
7. microphone test device according to claim 6, which is characterized in that the broadcasting switching switch (33) is connected in series to
The negative terminals of the loud speaker (31), and pass through L channel circuits of the 4th resistance R4 respectively with the earphone (32)
(321) connect with the right channel circuit of the earphone (32) (322), the L channel circuit (321) of the earphone (32) and described
The right channel circuit (322) of earphone (32) is parallel with one another, and is grounded together.
8. microphone test device according to claim 6, which is characterized in that the external power interface (41) is parallel to
On access between the energization pins and the 3rd capacitor C3, one end of the power change-over switch (43) passes through the 5th resistance
R5 is parallel on the access between the external power interface (41) and the energization pins, and the other end is connected to built-in power
(42) supply voltage interface, the power change-over switch (43) node in parallel with the external power interface (41) with it is described
Between the access of energization pins, the 4th capacitor C4 of ground connection and the 5th capacitor C5 of ground connection are parallel with respectively.
9. microphone test device according to claim 8, which is characterized in that the test probe (1) includes the first top
Pin and the second thimble, first thimble are used for access where being connected to the anode of microphone to be measured, and second thimble is used for
Access where being connected to the cathode of microphone to be measured.
10. microphone test device according to claim 9, which is characterized in that the filter module (5) includes the first electricity
One end of sensor L1 and the second inductor L2, the first inductor L1 are connected to second thimble, first inductor
The 6th capacitor C6 of ground connection is parallel between L1 and the access of second thimble connection, the first inductor L1's is another
End is directly grounded, while the other end of the first inductor L1 passes sequentially through the 6th resistance R6 and the 7th resistance R7 ground connection；Institute
The one end for stating the second inductor L2 is connected to first thimble, and the second inductor L2 is connected logical with first thimble
The 7th capacitor C7 of ground connection is parallel between road, the other end of the second inductor L2 passes sequentially through first resistor R1 and
One capacitor C1 is connected to the reversed input pin, while the other end of the second inductor L2 passes sequentially through the 8th resistance
R8, the 9th resistance R9 and the tenth resistance R10 are connected to the access between the external power interface (41) and the energization pins
On, the filter module (5) further includes the 8th capacitor C8, and one end of the 8th capacitor C8 is connected to the 6th resistance
Between R6 and the 7th resistance R7, the other end is connected between the 8th resistance R8 and the 9th resistance R9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721312025.0U CN207427481U (en) | 2017-10-11 | 2017-10-11 | A kind of microphone test device |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201721312025.0U CN207427481U (en) | 2017-10-11 | 2017-10-11 | A kind of microphone test device |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN207427481U true CN207427481U (en) | 2018-05-29 |
Family
ID=62311062
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201721312025.0U Expired - Fee Related CN207427481U (en) | 2017-10-11 | 2017-10-11 | A kind of microphone test device |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN207427481U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112399320A (en) * | 2019-08-16 | 2021-02-23 | 神讯电脑(昆山)有限公司 | Electret microphone detection circuit |
| CN118433603A (en) * | 2024-07-04 | 2024-08-02 | 歌尔股份有限公司 | Test circuit and headphone |
-
2017
- 2017-10-11 CN CN201721312025.0U patent/CN207427481U/en not_active Expired - Fee Related
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN112399320A (en) * | 2019-08-16 | 2021-02-23 | 神讯电脑(昆山)有限公司 | Electret microphone detection circuit |
| CN112399320B (en) * | 2019-08-16 | 2022-04-19 | 神讯电脑(昆山)有限公司 | Electret microphone detection circuit |
| CN118433603A (en) * | 2024-07-04 | 2024-08-02 | 歌尔股份有限公司 | Test circuit and headphone |
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| CF01 | Termination of patent right due to non-payment of annual fee |
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| CF01 | Termination of patent right due to non-payment of annual fee |