CN205596312U - Microphone amplifier circuit and electronic equipment - Google Patents
Microphone amplifier circuit and electronic equipment Download PDFInfo
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- CN205596312U CN205596312U CN201620213483.8U CN201620213483U CN205596312U CN 205596312 U CN205596312 U CN 205596312U CN 201620213483 U CN201620213483 U CN 201620213483U CN 205596312 U CN205596312 U CN 205596312U
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Abstract
The utility model discloses a microphone amplifier circuit and electronic equipment, wherein this microphone amplifier circuit including the attenuator circuit that is used for going on adjusting to input audio signal's amplitude, be used for to an amplifier circuit and the 2nd amplifier circuit provide reference voltage bias circuit, an amplifier circuit who is used for going on amplifying to the audio signal of input, be used for controlling attenuator circuit and adjust the 2nd amplifier circuit to the audio signal amplitude of input, attenuator circuit is connected with the load through first amplifying circuit's reverse input end, bias circuit is connected with first amplifying circuit and the 2nd amplifier circuit's syntropy input respectively, and the 2nd amplifier circuit's output is connected with attenuator circuit's controlled end, the 2nd amplifier circuit's syntropy input still is connected with the 2nd amplifier circuit's output, the 2nd amplifier circuit's reverse input end ground connection. The utility model discloses technical scheme have the AGC function and the cost lower.
Description
Technical field
This utility model relates to audio signal processing technique field, particularly to a kind of microphone amplifying circuit and the electronic equipment of applying this amplifying circuit.
Background technology
Microphone amplifying circuit generally has following two application circuit at present: a kind of is the single-stage or the amplification to microphone signal of the Cascaded amplification circuit realiration applying simple amplifier to form, this circuit without pre-attenuator does not have AGC control, it is readily formed the distortion of big signal, even if equipped with amplitude limiter circuit, also distortion phenomenon can be there is at clipping point；Another kind is to use special amplifier chip, such as MAX9814 chip, has AGC (Automatic Gain Control, automatic growth control) function, and shortcoming is that price is higher.
Utility model content
Main purpose of the present utility model is to provide a kind of microphone amplifying circuit, it is intended to realize a kind of that have an AGC function and lower-cost microphone amplifying circuit.
For achieving the above object, the utility model proposes a kind of microphone amplifying circuit, including attenuator circuit, biasing circuit, the first amplifying circuit and the second amplifying circuit；The input of described attenuator circuit accesses the audio signal of mike input, and the outfan of described attenuator circuit is connected with the reverse input end of described first amplifying circuit, and the controlled end of described attenuator circuit is connected with the outfan of described second amplifying circuit；The input in the same direction of described first amplifying circuit is connected with the first outfan of described biasing circuit, the output terminating load of described first amplifying circuit；The input in the same direction of described second amplifying circuit is connected with the second outfan of described biasing circuit, and the input in the same direction of described second amplifying circuit also outfan with described first amplifying circuit is connected, the reverse input end ground connection of described second amplifying circuit；Wherein
Described first amplifying circuit, for being amplified the audio signal of input；
Described attenuator circuit, for being adjusted the audio signal amplitude of input；
Described biasing circuit, for providing reference voltage to described first amplifying circuit and the second amplifying circuit；
Described second amplifying circuit, for the audio signal according to the first amplifying circuit output, controls described attenuator circuit and is adjusted the audio signal amplitude of input.
Preferably, described attenuator circuit includes the first resistance, the second resistance, the first electric capacity, the second electric capacity and the first switching tube；The first of described first resistance terminates the audio signal into mike input, and the second end of described first resistance is connected with the first end of described first electric capacity；Second end of described first electric capacity is connected through the first end of described second electric capacity with described second resistance；Second end of described second resistance is connected with the reverse input end of described first amplifying circuit；The input end grounding of described first switching tube, the outfan of described first switching tube is connected with the outfan of described second amplifying circuit, the controlled end of described first switching tube is connected with the second end of described first electric capacity, and the controlled end of described first switching tube also outfan with described first switching tube is connected.
Preferably, described microphone amplifying circuit also includes that current rectifying and wave filtering circuit, the input of described current rectifying and wave filtering circuit are connected with the outfan of described second amplifying circuit, and the outfan of described current rectifying and wave filtering circuit is connected with the controlled end of described attenuator circuit.
Preferably, described current rectifying and wave filtering circuit includes the 3rd resistance, the 4th resistance, the 3rd electric capacity, the 4th electric capacity, the first diode and the second diode；First end of described 3rd resistance is connected with the outfan of described first switching tube, and the second end of described 3rd resistance is connected with the first end of described 4th resistance；Second end of described 4th resistance is connected with the negative electrode of described first diode；The anode of described first diode is connected with the outfan of described second amplifying circuit；First end of described 3rd electric capacity is connected with the first end of described 4th resistance, the second end ground connection of described 3rd electric capacity；The first of described 4th electric capacity is connected with the second end of described 4th resistance, the second end ground connection of described 4th electric capacity；The plus earth of described second diode, the negative electrode of described second diode is connected with the anode of described first diode.
Preferably, described first amplifying circuit includes the first operational amplifier, the 5th resistance and the 5th electric capacity；The input in the same direction of described first operational amplifier is connected with the first outfan of described biasing circuit, the reverse input end of described first operational amplifier is connected with the second end of described second resistance, the outfan of described first operational amplifier is connected with the first end of described 5th electric capacity, the second terminating load of described 5th electric capacity；First end of described 5th resistance is connected with the reverse input end of described first operational amplifier, and the second end of described 5th resistance is connected with the outfan of described first operational amplifier.
Preferably, described second amplifying circuit includes the second operational amplifier, the 6th resistance, the 7th resistance, the 6th electric capacity, the 7th electric capacity and the 8th electric capacity；The input in the same direction of described second operational amplifier is connected with the second outfan of described biasing circuit, and the reverse input end of described second operational amplifier is connected with the first end of described 6th resistance；Second end of described 6th resistance is through described 6th capacity earth；The input in the same direction of described second operational amplifier is also connected with the outfan of described first operational amplifier through described 7th electric capacity；The outfan of described second operational amplifier is connected with the anode of described first diode through described 8th electric capacity.
Preferably, described first operational amplifier and described second operational amplifier are integrated in same amplifier chip.
Preferably, described switching tube uses 2N3904 audion.
Preferably, described voltage offset electric circuit includes power supply, the 9th electric capacity, the 8th resistance, the 9th resistance, the tenth resistance and the 11st resistance；First end of described 8th resistance is connected with described power supply, and the second end of described 8th resistance is through described 9th resistance eutral grounding, and the second end of described 8th resistance also input in the same direction with described first amplifying circuit is connected；First end of described tenth resistance is connected with described power supply, and the second end of described tenth resistance is through described 11st resistance eutral grounding, and the second end of described tenth resistance also input in the same direction with described second amplifying circuit is connected；First end of described 9th electric capacity is connected with described power supply, the second end ground connection of described 9th electric capacity.
A kind of electronic equipment, described electronic equipment includes that microphone amplifying circuit as above, described microphone amplifying circuit include attenuator circuit, biasing circuit, the first amplifying circuit and the second amplifying circuit；The input of described attenuator circuit accesses the audio signal of mike input, and the outfan of described attenuator circuit is connected with the reverse input end of described first amplifying circuit, and the controlled end of described attenuator circuit is connected with the outfan of described second amplifying circuit；The input in the same direction of described first amplifying circuit is connected with the first outfan of described biasing circuit, the output terminating load of described first amplifying circuit；The input in the same direction of described second amplifying circuit is connected with the second outfan of described biasing circuit, and the input in the same direction of described second amplifying circuit also outfan with described first amplifying circuit is connected, the reverse input end ground connection of described second amplifying circuit；Wherein said first amplifying circuit, for being amplified the audio signal of input；Described attenuator circuit, for being adjusted the audio signal amplitude of input；Described biasing circuit, for providing reference voltage to described first amplifying circuit and the second amplifying circuit；Described second amplifying circuit, for the audio signal according to the first amplifying circuit output, controls described attenuator circuit and is adjusted the audio signal amplitude of input.
Technical solutions of the utility model, by arranging attenuator circuit, biasing circuit, the first amplifying circuit and the second amplifying circuit, define a kind of microphone amplifying circuit.Described biasing circuit provides reference voltage to described first amplifying circuit and the second amplifying circuit, the audio signal of input is amplified by the first amplifying circuit, the audio signal that second amplifying circuit exports according to the first amplifying circuit, control described attenuator circuit the audio signal amplitude of input is adjusted so that the first amplifying circuit to the gain stabilization of input audio signal in set point.Technical solutions of the utility model use lower-cost microphone amplifying circuit to achieve a kind of microphone amplifying circuit with AGC function, and cost is relatively low, and cost performance is high.
Accompanying drawing explanation
In order to be illustrated more clearly that this utility model embodiment or technical scheme of the prior art, the accompanying drawing used required in embodiment or description of the prior art will be briefly described below, apparently, accompanying drawing in describing below is only embodiments more of the present utility model, for those of ordinary skill in the art, on the premise of not paying creative work, it is also possible to obtain other accompanying drawing according to the structure shown in these accompanying drawings.
Fig. 1 is the functional block diagram of this utility model microphone amplifying circuit one embodiment；
Fig. 2 is the circuit structure diagram of this utility model microphone amplifying circuit one embodiment.
Drawing reference numeral illustrates:
The realization of this utility model purpose, functional characteristics and advantage will in conjunction with the embodiments, are described further referring to the drawings.
Detailed description of the invention
Below in conjunction with the accompanying drawing in this utility model embodiment, the technical scheme in this utility model embodiment is clearly and completely described, it is clear that described embodiment is only a part of embodiment of the present utility model rather than whole embodiments.Based on the embodiment in this utility model, the every other embodiment that those of ordinary skill in the art are obtained under not making creative work premise, broadly fall into the scope of this utility model protection.
It is to be appreciated that be only used for describing purpose as related to the description of " first ", " second " etc. in this utility model, and it is not intended that indicate or imply its relative importance or the implicit quantity indicating indicated technical characteristic.Thus, define " first ", the feature of " second " can express or implicitly include at least one this feature.Additionally; technical scheme between each embodiment can be combined with each other; but must be based on those of ordinary skill in the art are capable of; when technical scheme combination occur conflicting maybe cannot realize time will be understood that the combination of this technical scheme does not exists, the most not this utility model require protection domain within.
The utility model proposes a kind of microphone amplifying circuit.
With reference to Fig. 1, in this utility model embodiment, this microphone amplifying circuit includes attenuator circuit the 10, first amplifying circuit the 20, second amplifying circuit 30 and biasing circuit 40；The input of described attenuator circuit 10 accesses the audio signal of mike input, the outfan of described attenuator circuit 10 is connected with the reverse input end of described first amplifying circuit 20, and the controlled end of described attenuator circuit 10 is connected with the outfan of described second amplifying circuit 30；The input in the same direction of described first amplifying circuit 20 is connected with the first outfan of described biasing circuit 40, the output terminating load of described first amplifying circuit 20；The input in the same direction of described second amplifying circuit 30 is connected with the second outfan of described biasing circuit 40, the input in the same direction of described second amplifying circuit 30 also outfan with described first amplifying circuit 20 is connected, the reverse input end ground connection of described second amplifying circuit 30.
Wherein, described first amplifying circuit 20 is for being amplified the audio signal of input；Described attenuator circuit 10 is for being adjusted the audio signal amplitude of input；Described biasing circuit 40 is for providing reference voltage to described first amplifying circuit 20 and the second amplifying circuit 30；Described second amplifying circuit 30, for the audio signal according to the first amplifying circuit 20 output, controls described attenuator circuit 10 and is adjusted the audio signal amplitude of input.
It should be noted that access an attenuator circuit 10 after the audio signal input of outside, the first amplifying circuit 20 is reversely to amplify；Second amplifying circuit 30 amplifies for forward, second amplifying circuit 30 forward amplifies output one control voltage and controls the attenuation of attenuator circuit 10, to adjust the output to the audio signal amplitude of the first amplifying circuit 20, reach the purpose of the output extremely automatic growth control of load audio signal.
Technical solutions of the utility model, by arranging attenuator circuit 10, biasing circuit the 40, first amplifying circuit 20 and the second amplifying circuit 30, define a kind of microphone amplifying circuit.Described biasing circuit 40 provides reference voltage to described first amplifying circuit 20 and the second amplifying circuit 30, the audio signal of input is amplified by the first amplifying circuit 20, the audio signal that second amplifying circuit 30 exports according to the first amplifying circuit 20, control described attenuator circuit 10 watt level of audio signal of input is adjusted so that the first amplifying circuit 20 to the gain stabilization of input audio signal in set point.Technical solutions of the utility model use lower-cost microphone amplifying circuit to achieve a kind of microphone amplifying circuit with AGC function, and cost is relatively low, and cost performance is high.
Specifically, refer to Fig. 2, described attenuator circuit 10 includes the first resistance R1, the second resistance R2, the first electric capacity C1, the second electric capacity C2 and the first switching tube Q1；The first of described first resistance R1 terminates the audio signal into mike input, and second end of described first resistance R1 is connected with first end of described first electric capacity C1；Second end of described first electric capacity C1 is connected through first end of described second electric capacity C2 with described second resistance R2；Second end of described second resistance R2 is connected with the reverse input end of described first amplifying circuit 20；The input end grounding of described first switching tube Q1, the outfan of described first switching tube Q1 is connected with the outfan of described second amplifying circuit 30, the controlled end of described first switching tube Q1 is connected with second end of described first electric capacity C1, and the controlled end of described first switching tube Q1 also outfan with described first switching tube Q1 is connected.
Further, described microphone amplifying circuit also includes current rectifying and wave filtering circuit 50, the input of described current rectifying and wave filtering circuit 50 is connected with the outfan of described second amplifying circuit 30, and the outfan of described current rectifying and wave filtering circuit 50 is connected with the controlled end of described attenuator circuit 10.
It should be noted that after current rectifying and wave filtering circuit 50 voltage rectification after filtering that second amplifying circuit 30 is exported, obtain the DC voltage stable, ripple is few.
Specifically, described current rectifying and wave filtering circuit 50 includes the 3rd resistance R3, the 4th resistance R4, the 3rd electric capacity C3, the 4th electric capacity C4, the first diode D1 and the second diode D2；First end of described 3rd resistance R3 is connected with the outfan of described first switching tube Q1, and second end of described 3rd resistance R3 is connected with first end of described 4th resistance R4；Second end of described 4th resistance R4 is connected with the negative electrode of described first diode D1；The anode of described first diode D1 is connected with the outfan of described second amplifying circuit 30；First end of described 3rd electric capacity C3 is connected with first end of described 4th resistance R4, the second end ground connection of described 3rd electric capacity C3；The first of described 4th electric capacity C4 is connected with second end of described 4th resistance R4, the second end ground connection of described 4th electric capacity C4；The plus earth of described second diode D2, the negative electrode of described second diode D2 is connected with the anode of described first diode D1.
Specifically, described first amplifying circuit 20 includes the first operational amplifier U1, the 5th resistance R5 and the 5th electric capacity C5；The input in the same direction of described first operational amplifier U1 is connected with the first outfan of described biasing circuit 40, the reverse input end of described first operational amplifier U1 is connected with second end of described second resistance R2, the outfan of described first operational amplifier U1 is connected with first end of described 5th electric capacity C5, second terminating load of described 5th electric capacity C5；First end of described 5th resistance R5 is connected with the reverse input end of described first operational amplifier U1, and second end of described 5th resistance R5 is connected with the outfan of described first operational amplifier U1.
It should be noted that the 5th electric capacity C5 is capacitance, the 5th resistance R5 is feedback resistance, plays the effect of regulation the first amplifying circuit 20 gain so that the actual gain of the first amplifying circuit 20 levels off to setting gain.
Specifically, described second amplifying circuit 30 includes the second operational amplifier U2, the 6th resistance R6, the 7th resistance R7, the 6th electric capacity C6, the 7th electric capacity C7 and the 8th electric capacity C8；The input in the same direction of described second operational amplifier U2 is connected with the second outfan of described biasing circuit 40, and the reverse input end of described second operational amplifier U2 is connected with first end of described 6th resistance R6；Second end of described 6th resistance R6 is through described 6th electric capacity C6 ground connection；The input in the same direction of described second operational amplifier U2 also outfan through described 7th electric capacity C7 with described first operational amplifier U1 is connected；The outfan of described second operational amplifier U2 is connected through the anode of described 8th electric capacity C8 with described first diode D1.
It can be readily appreciated that the 7th resistance R7 is feedback resistance, play the effect of regulation the second amplifying circuit 30 gain so that the actual gain of the second amplifying circuit 30 levels off to setting gain, and the 7th electric capacity C7 and the 8th electric capacity C8 is capacitance.
Further, described first operational amplifier U1 and described second operational amplifier U2 is integrated in same amplifier chip.In the present embodiment, use double operational chip, simplify circuit structure, reduce cost.
In the present embodiment, described switching tube uses 2N3904 audion.
Specifically, described biasing circuit 40 includes power supply VCC1, the 9th electric capacity C9, the 8th resistance R8, the 9th resistance R9, the tenth resistance R10 and the 11st resistance R11；First end of described 8th resistance R8 is connected with described power supply VCC1, and second end of described 8th resistance R8 is through described 9th resistance R9 ground connection, and second end of described 8th resistance R8 also input in the same direction with described first amplifying circuit 20 is connected；First end of described tenth resistance R10 is connected with described power supply VCC1, and second end of described tenth resistance R10 is through described 11st resistance R11 ground connection, and second end of described tenth resistance R10 also input in the same direction with described second amplifying circuit 30 is connected；First end of described 9th electric capacity C9 is connected with described power supply VCC1, the second end ground connection of described 9th electric capacity C9.
It should be noted that the 8th resistance R8 and the 9th resistance R9 is divider resistance, after the output voltage of power supply VCC1 is carried out dividing potential drop, provide reference voltage to the first amplifying circuit 20；Tenth resistance R10 and the 11st resistance R11 is also divider resistance, provides reference voltage to the second amplifying circuit 30 after the output voltage of power supply VCC1 is carried out dividing potential drop.9th electric capacity C9 is for being filtered power supply VCC1.
First operational amplifier U1 also includes that power end and earth terminal, the power end of the first operational amplifier U1 are connected with described power supply VCC1, the earth terminal ground connection of the first operational amplifier U1.
Second operational amplifier U2 also includes that power end and earth terminal, the power end of the second operational amplifier U2 are connected with described power supply VCC1, the earth terminal ground connection of the second operational amplifier U2.
In conjunction with physical circuit, technical solutions of the utility model are illustrated:
When the audio signal amplitude of outside input increases, the audio signal amplitude of the first operational amplifier U1 reverse input end input also increases, and the audio signal amplitude of the first operational amplifier U1 output also increases；The corresponding audio signal voltage amplitude by the 7th electric capacity C7 input to the second operational amplifier U2 input in the same direction increases, second operational amplifier U2 output voltage amplitude increases, therefore the first switching tube Q1 collector voltage raises, thus the first switching tube Q1 conducting, the audio signal amplitude inputted to the first operational amplifier U1 is reduced, and the audio signal voltage amplitude of the first corresponding operational amplifier U1 output to load reduces.
Should be readily understood that, when the audio signal power reduction of outside input, first switching tube Q1 collector voltage reduces, first switching tube Q1 turns off, the audio signal amplitude inputted to the first operational amplifier U1 is increased, and the audio signal voltage amplitude of the first corresponding operational amplifier U1 output to load raises.
Technical solutions of the utility model use the amplifier chip (integrated described first operational amplifier U1 and described second operational amplifier U2) that price is relatively low, it is achieved that a kind of microphone amplifying circuit with AGC function, have higher cost performance.
This utility model also proposes a kind of electronic equipment, this electronic equipment includes above-mentioned microphone amplifying circuit, the concrete structure of this microphone amplifying circuit is with reference to above-described embodiment, owing to this electronic equipment have employed whole technical schemes of above-mentioned all embodiments, the most at least having all beneficial effects that the technical scheme of above-described embodiment is brought, this is no longer going to repeat them.
This electronic equipment can be television set, sound equipment etc..
The foregoing is only preferred embodiment of the present utility model; not thereby the scope of the claims of the present utility model is limited; every under inventive concept of the present utility model; utilize the equivalent structure transformation that this utility model description and accompanying drawing content are made, or directly/be indirectly used in other relevant technical fields and be included in scope of patent protection of the present utility model.
Claims (10)
1. a microphone amplifying circuit, it is characterised in that include attenuator circuit, biasing circuit, the first amplifying circuit and the second amplifying circuit；The input of described attenuator circuit accesses the audio signal of mike input, and the outfan of described attenuator circuit is connected with the reverse input end of described first amplifying circuit, and the controlled end of described attenuator circuit is connected with the outfan of described second amplifying circuit；The input in the same direction of described first amplifying circuit is connected with the first outfan of described biasing circuit, the output terminating load of described first amplifying circuit；The input in the same direction of described second amplifying circuit is connected with the second outfan of described biasing circuit, and the input in the same direction of described second amplifying circuit also outfan with described first amplifying circuit is connected, the reverse input end ground connection of described second amplifying circuit；Wherein
Described attenuator circuit, for being adjusted the audio signal amplitude of input；
Described first amplifying circuit, is amplified for the audio signal inputting described attenuator circuit；
Described biasing circuit, for providing reference voltage to described first amplifying circuit and the second amplifying circuit；
Described second amplifying circuit, for the audio signal according to the first amplifying circuit output, controls described attenuator circuit and is adjusted the audio signal amplitude of input.
2. microphone amplifying circuit as claimed in claim 1, it is characterised in that described attenuator circuit includes the first resistance, the second resistance, the first electric capacity, the second electric capacity and the first switching tube；The first of described first resistance terminates the audio signal into mike input, and the second end of described first resistance is connected with the first end of described first electric capacity；Second end of described first electric capacity is connected through the first end of described second electric capacity with described second resistance；Second end of described second resistance is connected with the reverse input end of described first amplifying circuit；The input end grounding of described first switching tube, the outfan of described first switching tube is connected with the outfan of described second amplifying circuit, the controlled end of described first switching tube is connected with the second end of described first electric capacity, and the controlled end of described first switching tube also outfan with described first switching tube is connected.
3. microphone amplifying circuit as claimed in claim 2, it is characterized in that, described microphone amplifying circuit also includes current rectifying and wave filtering circuit, the input of described current rectifying and wave filtering circuit is connected with the outfan of described second amplifying circuit, and the outfan of described current rectifying and wave filtering circuit is connected with the controlled end of described attenuator circuit.
4. microphone amplifying circuit as claimed in claim 3, it is characterised in that described current rectifying and wave filtering circuit includes the 3rd resistance, the 4th resistance, the 3rd electric capacity, the 4th electric capacity, the first diode and the second diode；First end of described 3rd resistance is connected with the outfan of described first switching tube, and the second end of described 3rd resistance is connected with the first end of described 4th resistance；Second end of described 4th resistance is connected with the negative electrode of described first diode；The anode of described first diode is connected with the outfan of described second amplifying circuit；First end of described 3rd electric capacity is connected with the first end of described 4th resistance, the second end ground connection of described 3rd electric capacity；The first of described 4th electric capacity is connected with the second end of described 4th resistance, the second end ground connection of described 4th electric capacity；The plus earth of described second diode, the negative electrode of described second diode is connected with the anode of described first diode.
5. microphone amplifying circuit as claimed in claim 4, it is characterised in that described first amplifying circuit includes the first operational amplifier, the 5th resistance and the 5th electric capacity；The input in the same direction of described first operational amplifier is connected with the first outfan of described biasing circuit, the reverse input end of described first operational amplifier is connected with the second end of described second resistance, the outfan of described first operational amplifier is connected with the first end of described 5th electric capacity, the second terminating load of described 5th electric capacity；First end of described 5th resistance is connected with the reverse input end of described first operational amplifier, and the second end of described 5th resistance is connected with the outfan of described first operational amplifier.
6. microphone amplifying circuit as claimed in claim 5, it is characterised in that described second amplifying circuit includes the second operational amplifier, the 6th resistance, the 7th resistance, the 6th electric capacity, the 7th electric capacity and the 8th electric capacity；The input in the same direction of described second operational amplifier is connected with the second outfan of described biasing circuit, and the reverse input end of described second operational amplifier is connected with the first end of described 6th resistance；Second end of described 6th resistance is through described 6th capacity earth；The input in the same direction of described second operational amplifier is also connected with the outfan of described first operational amplifier through described 7th electric capacity；The outfan of described second operational amplifier is connected with the anode of described first diode through described 8th electric capacity.
7. microphone amplifying circuit as claimed in claim 6, it is characterised in that described first operational amplifier and described second operational amplifier are integrated in same amplifier chip.
8. microphone amplifying circuit as claimed in claim 7, it is characterised in that described switching tube uses 2N3904 audion.
9. microphone amplifying circuit as claimed in claim 1, it is characterised in that described voltage offset electric circuit includes power supply, the 9th electric capacity, the 8th resistance, the 9th resistance, the tenth resistance and the 11st resistance；First end of described 8th resistance is connected with described power supply, and the second end of described 8th resistance is through described 9th resistance eutral grounding, and the second end of described 8th resistance also input in the same direction with described first amplifying circuit is connected；First end of described tenth resistance is connected with described power supply, and the second end of described tenth resistance is through described 11st resistance eutral grounding, and the second end of described tenth resistance also input in the same direction with described second amplifying circuit is connected；First end of described 9th electric capacity is connected with described power supply, the second end ground connection of described 9th electric capacity.
10. an electronic equipment, it is characterised in that described electronic equipment includes the microphone amplifying circuit as described in claim 1-9 any one.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620213483.8U CN205596312U (en) | 2016-03-16 | 2016-03-16 | Microphone amplifier circuit and electronic equipment |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620213483.8U CN205596312U (en) | 2016-03-16 | 2016-03-16 | Microphone amplifier circuit and electronic equipment |
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| CN205596312U true CN205596312U (en) | 2016-09-21 |
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| CN201620213483.8U Active CN205596312U (en) | 2016-03-16 | 2016-03-16 | Microphone amplifier circuit and electronic equipment |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108924704A (en) * | 2018-08-31 | 2018-11-30 | 延锋伟世通电子科技（南京）有限公司 | Vehicle entertainment system stablizes the Microphone audio input circuit of frequency response output |
| WO2023184625A1 (en) * | 2022-04-01 | 2023-10-05 | 瑞声声学科技(深圳)有限公司 | Microphone amplification circuit design method, and microphone amplification circuit |
-
2016
- 2016-03-16 CN CN201620213483.8U patent/CN205596312U/en active Active
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108924704A (en) * | 2018-08-31 | 2018-11-30 | 延锋伟世通电子科技（南京）有限公司 | Vehicle entertainment system stablizes the Microphone audio input circuit of frequency response output |
| WO2023184625A1 (en) * | 2022-04-01 | 2023-10-05 | 瑞声声学科技(深圳)有限公司 | Microphone amplification circuit design method, and microphone amplification circuit |
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