CN203563186U - Noise reduction circuit and voice audio driving circuit provided with same - Google Patents
Noise reduction circuit and voice audio driving circuit provided with same Download PDFInfo
- Publication number
- CN203563186U CN203563186U CN201320617456.3U CN201320617456U CN203563186U CN 203563186 U CN203563186 U CN 203563186U CN 201320617456 U CN201320617456 U CN 201320617456U CN 203563186 U CN203563186 U CN 203563186U
- Authority
- CN
- China
- Prior art keywords
- resistance
- triode
- capacitor
- circuit
- power amplifier
- Prior art date
- Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
- Expired - Fee Related
Links
Images
Landscapes
- Tone Control, Compression And Expansion, Limiting Amplitude (AREA)
Abstract
The utility model discloses a noise reduction circuit and a voice audio driving circuit provided with the same. The noise reduction circuit comprises a resistor R3, a resistor R4, a resistor R5, a capacitor C2 and a triode Q1. One end of the capacitor C2 is connected with a high level VCC, and the other end of the capacitor C2 is grounded. A base electrode of the triode Q1 is connected with a signal output end of the main control unit MCU through the resistor R5 and is grounded through the resistor R4. A collector electrode of the triode Q1 is connected with high level VCC through the resistor R3 and outputs processed signals. An emitter electrode of the triode Q1 is grounded. According to the utility model, the noise reduction circuit is added on the basis of the prior art, voice audio signals output by the main control unit MCU firstly pass through the noise reduction circuit, then is subjected to the filtering and amplifying processing of a high-pass filtering circuit and a gain amplification circuit, then enters a voice power amplifier IC1, and drives audio equipment after the processing of the voice power amplifier IC1, so that the noises of the audio equipment can be reduced or eliminated.
Description
Technical field
The utility model relates to circuit engineering field, in particular to a kind of Dolby circuit and have its speech audio drive circuit.
Background technology
Known ground, in speech audio drive circuit, main control MCU (Micro Control Unit, micro-control unit) output voice signal, after filtering, gain and amplify, as the input signal of phonetic speech power amplifier IC1, through exporting after the processing of IC1 with driving audio frequency apparatus.
As shown in Figure 1, it shows a kind of speech audio drive circuit of the prior art, its phonetic speech power amplifier IC1 is phonetic speech power amplifying device, the member 1 of described 111 indications provides power supply for phonetic speech power amplifier IC1, wherein, described member 1 comprises capacitor C 3 ' in parallel and EC2 ', a common termination high level VDD of described capacitor C 3 ' and E C2 ' is also connected to the first power input of phonetic speech power amplifier IC1, another common second source input of holding ground connection and being connected to phonetic speech power amplifier IC1 of described capacitor C 3 ' and E C2 '.
The gain amplifying circuit that the member 2 of described 112 indications is audio signal, described member 2 comprises the resistance R 2 ' that are connected between two of phonetic speech power amplifier IC1 gain class pins, and the resistance R 1 ' being connected with resistance R 2 ' one end with one of them the gain class pin of phonetic speech power amplifier IC1 respectively.
The member 3 of described 113 indications forms high pass filter by resistance R 1 ' and the capacitor C 1 ' of connecting, one end of described resistance R 1 ' is connected to one of them the gain class pin of phonetic speech power amplifier IC1, and one end of described capacitor C 1 ' is connected to the audio signal output end of main control MCU.In addition, continuation is with reference to shown in figure 1, described electric capacity EC1 ' is the filter capacitor of phonetic speech power amplifier IC1, its one end is connected to respectively two filtering class pins of phonetic speech power amplifier IC1, its other end ground connection, main control MCU output voice audio signals, after processing through filtering, the amplification of member 3 and member 2, enter phonetic speech power amplifier IC1, and drive signal to drive audio frequency apparatus by output audio after the processing of phonetic speech power amplifier IC1.
But in the middle of actual application, because main control MCU is except driving phonetic speech power amplifier IC1, also often with other loads, for example digital screen, motor etc., in the time of main control MCU output audio signal, also output in order to drive other compared with heavy load (as digital screen, motor etc.) driving signal, now main control MCU output in order to drive the audio signal of phonetic speech power amplifier IC1 may occur fluctuation or noise, the small fluctuation being mingled with in described driving signal or noise are exported to audio frequency apparatus after amplifying through the gain of phonetic speech power amplifier IC1, can cause audio frequency apparatus to occur larger noise.
Utility model content
In order to solve, to be mingled with in a subtle way small noise and finally can to cause audio frequency apparatus to occur the problem of larger noise in audio signal, the purpose of this utility model is the speech audio drive circuit that a kind of Dolby circuit is provided and has it.
The utility model is realized by the following technical solutions:
A kind of Dolby circuit, it comprises resistance R 3, resistance R 4, resistance R 5, capacitor C 2 and triode Q1, one termination high level VCC of capacitor C 2, its other end ground connection, the base stage of triode Q1 is connected with the signal output part of main control unit MCU by resistance R 5 and passes through resistance R 4 ground connection, the collector electrode of triode Q1 is connected to high level VCC and output processing signals, the grounded emitter of triode Q1 by resistance R 3.
A kind of speech audio drive circuit, it comprises:
Phonetic speech power amplifier IC1;
Power circuit;
Gain amplifying circuit;
High-pass filtering circuit;
And Dolby circuit, it comprises resistance R 3, resistance R 4, resistance R 5, capacitor C 2 and triode Q1, one termination high level VCC of capacitor C 2, its other end ground connection, the base stage of triode Q1 is connected with the audio signal output end of main control unit MCU by resistance R 5 and passes through resistance R 4 ground connection, the collector electrode of triode Q1 is connected to high level VCC and is connected to the input of described high-pass filtering circuit, the grounded emitter of triode Q1 by resistance R 3.
Preferably, described power circuit comprises capacitor C in parallel 3 and EC2, a common termination high level VDD of described capacitor C 3 and EC2 is also connected to the first power input of phonetic speech power amplifier IC1, and another common end ground connection of described capacitor C 3 and EC2 is also connected to second source input of phonetic speech power amplifier IC1.
Preferably, described gain amplifying circuit comprises the resistance R 2 that are connected between two of phonetic speech power amplifier IC1 gain class pins, and the resistance R 1 being connected with resistance R 2 one end with one of them the gain class pin of phonetic speech power amplifier IC1 respectively.
Preferably, described high-pass filtering circuit comprises resistance R 1 and the capacitor C 1 of series connection, and one end of described resistance R 1 is connected to one of them the gain class pin of phonetic speech power amplifier IC1, and one end of described capacitor C 1 is connected to the collector electrode of triode Q1.
The utility model increases Dolby circuit on the basis of existing technology, described Dolby circuit can filtering main control MCU the interference that produces of the voice audio signals unusual fluctuations of output, the voice audio signals of main control MCU output, first pass through Dolby circuit, then by filtering, the amplification of high-pass filtering circuit and gain amplifying circuit, process, enter again phonetic speech power amplifying device IC1, after processing by phonetic speech power amplifier IC1, drive audio frequency apparatus, can reduce or remove like this noise of audio frequency apparatus.
Accompanying drawing explanation
Fig. 1 is the circuit diagram of the speech audio drive circuit that provides of prior art;
Fig. 2 is the circuit diagram of the Dolby circuit that provides of the utility model embodiment;
Fig. 3 is the circuit diagram of the speech audio drive circuit that provides of the utility model embodiment.
Realization, functional characteristics and the excellent effect of the utility model object, be described further below in conjunction with specific embodiment and accompanying drawing.
Embodiment
Below in conjunction with the drawings and specific embodiments, technical scheme described in the utility model is described in further detail, so that those skilled in the art can better understand the utility model being implemented, but illustrated embodiment is not as to restriction of the present utility model.
As shown in Figure 2, a kind of Dolby circuit that the utility model embodiment provides, it comprises resistance R 3, resistance R 4, resistance R 5, capacitor C 2 and triode Q1, one termination high level VCC of capacitor C 2, its other end ground connection, the base stage of triode Q1 is connected with the signal output part of main control unit MCU by resistance R 5 and by resistance R 4 ground connection, the collector electrode of triode Q1 is connected to high level VCC and output processing signals, the grounded emitter of triode Q1 by resistance R 3.
The effect of described Dolby circuit is the wave noise of the signal (as audio signal) of filtering main control MCU output, the signal of main control MCU output is as the control signal of triode Q1 in this Dolby circuit, as long as the signal voltage of main control MCU output is greater than the conducting voltage Vi of triode Q1, triode Q1 will conducting, when the signal voltage of main control MCU output is less than the conducting voltage Vi of triode Q1, triode Q1 closes, the output that is to say triode Q1 is only opened, close two kinds of signals, when triode Q1 conducting, this Dolby circuit is exported the low level of 0V, when triode Q1 closes, this Dolby circuit is exported the high level of VCC.The signal that reaches the output of this Dolby circuit filtering main control MCU with this is due to interference that unusual fluctuations were produced.
As shown in Figure 3, the utility model embodiment also provides a kind of speech audio drive circuit, and it comprises:
Phonetic speech power amplifier IC1;
Gain amplifying circuit 212;
High-pass filtering circuit 213;
And Dolby circuit 214, it comprises resistance R 3, resistance R 4, resistance R 5, capacitor C 2 and triode Q1, one termination high level VCC of capacitor C 2, its other end ground connection, the base stage of triode Q1 is connected with the audio signal output end of main control unit MCU by resistance R 5 and passes through resistance R 4 ground connection, the collector electrode of triode Q1 is connected to high level VCC and is connected to the input of described high-pass filtering circuit 213, the grounded emitter of triode Q1 by resistance R 3.
In like manner, the effect of described Dolby circuit 214 is wave noises of the audio signal of filtering main control MCU output, the audio signal of main control MCU output is as the control signal of triode Q1 in this Dolby circuit 214, as long as the audio signal voltage of main control MCU output is greater than the conducting voltage Vi of triode Q1, triode Q1 will conducting, when the audio signal voltage of main control MCU output is less than the conducting voltage Vi of triode Q1, triode Q1 closes, the output that is to say triode Q1 is only opened, close two kinds of signals, when triode Q1 conducting, the low level of 214 output 0V of this Dolby circuit, when triode Q1 closes, the high level of 214 output VCC of this Dolby circuit.The audio signal that reaches the 214 filtering main control MCU outputs of this Dolby circuit with this is due to interference that unusual fluctuations were produced.
In the present embodiment, described power circuit 211 comprises capacitor C in parallel 3 and EC2, a common termination high level VDD of described capacitor C 3 and EC2 is also connected to the first power input of phonetic speech power amplifier IC1, and another common end ground connection of described capacitor C 3 and EC2 is also connected to second source input of phonetic speech power amplifier IC1.
In the present embodiment, described gain amplifying circuit 212 comprises the resistance R 2 that are connected between two of phonetic speech power amplifier IC1 gain class pins, and the resistance R 1 being connected with resistance R 2 one end with one of them the gain class pin of phonetic speech power amplifier IC1 respectively.
In the present embodiment, described high-pass filtering circuit 213 comprises resistance R 1 and the capacitor C 1 of series connection, and one end of described resistance R 1 is connected to one of them the gain class pin of phonetic speech power amplifier IC1, and one end of described capacitor C 1 is connected to the collector electrode of triode Q1.
The foregoing is only preferred embodiment of the present utility model; not thereby limit the scope of the claims of the present utility model; every equivalent structure or conversion of equivalent flow process that utilizes the utility model specification and accompanying drawing content to do; or be directly or indirectly used in other relevant technical fields, be all in like manner included in scope of patent protection of the present utility model.
Claims (5)
1. a Dolby circuit, it is characterized in that, comprise resistance R 3, resistance R 4, resistance R 5, capacitor C 2 and triode Q1, one termination high level VCC of capacitor C 2, its other end ground connection, the base stage of triode Q1 is connected with the signal output part of main control unit MCU by resistance R 5 and by resistance R 4 ground connection, the collector electrode of triode Q1 is connected to high level VCC and output processing signals, the grounded emitter of triode Q1 by resistance R 3.
2. a speech audio drive circuit, is characterized in that, comprising:
Phonetic speech power amplifier IC1;
Power circuit;
Gain amplifying circuit;
High-pass filtering circuit;
And Dolby circuit, it comprises resistance R 3, resistance R 4, resistance R 5, capacitor C 2 and triode Q1, one termination high level VCC of capacitor C 2, its other end ground connection, the base stage of triode Q1 is connected with the audio signal output end of main control unit MCU by resistance R 5 and passes through resistance R 4 ground connection, the collector electrode of triode Q1 is connected to high level VCC and is connected to the input of described high-pass filtering circuit, the grounded emitter of triode Q1 by resistance R 3.
3. speech audio drive circuit as claimed in claim 2, it is characterized in that, described power circuit comprises capacitor C in parallel 3 and EC2, a common termination high level VDD of described capacitor C 3 and EC2 is also connected to the first power input of phonetic speech power amplifier IC1, and another common end ground connection of described capacitor C 3 and EC2 is also connected to second source input of phonetic speech power amplifier IC1.
4. speech audio drive circuit as claimed in claim 2, it is characterized in that, described gain amplifying circuit comprises the resistance R 2 that are connected between two of phonetic speech power amplifier IC1 gain class pins, and the resistance R 1 being connected with resistance R 2 one end with one of them the gain class pin of phonetic speech power amplifier IC1 respectively.
5. speech audio drive circuit as claimed in claim 2, it is characterized in that, described high-pass filtering circuit comprises resistance R 1 and the capacitor C 1 of series connection, one end of described resistance R 1 is connected to one of them the gain class pin of phonetic speech power amplifier IC1, and one end of described capacitor C 1 is connected to the collector electrode of triode Q1.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320617456.3U CN203563186U (en) | 2013-10-08 | 2013-10-08 | Noise reduction circuit and voice audio driving circuit provided with same |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201320617456.3U CN203563186U (en) | 2013-10-08 | 2013-10-08 | Noise reduction circuit and voice audio driving circuit provided with same |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN203563186U true CN203563186U (en) | 2014-04-23 |
Family
ID=50512876
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201320617456.3U Expired - Fee Related CN203563186U (en) | 2013-10-08 | 2013-10-08 | Noise reduction circuit and voice audio driving circuit provided with same |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN203563186U (en) |
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106356756A (en) * | 2016-08-30 | 2017-01-25 | 合肥智博电气有限公司 | Comprehensive switch cabinet state indicator |
| CN113284582A (en) * | 2021-05-14 | 2021-08-20 | 徐州市康复医院 | Headset type music treatment device |
-
2013
- 2013-10-08 CN CN201320617456.3U patent/CN203563186U/en not_active Expired - Fee Related
Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106356756A (en) * | 2016-08-30 | 2017-01-25 | 合肥智博电气有限公司 | Comprehensive switch cabinet state indicator |
| CN113284582A (en) * | 2021-05-14 | 2021-08-20 | 徐州市康复医院 | Headset type music treatment device |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN101400009B (en) | Microphone circuit | |
| CN203537555U (en) | Audio device | |
| CN102263537B (en) | Control circuit of linear motor of mobile terminal | |
| CN203933898U (en) | A kind of VGA CARD is eliminated circuit and active noise reduction earphone | |
| CN203563186U (en) | Noise reduction circuit and voice audio driving circuit provided with same | |
| CN102118668B (en) | Loudspeaker system and loudspeaker driving circuit | |
| CN201682458U (en) | Automatic gain control magnifier and low noise hearing aid system | |
| CN205793154U (en) | Earphone drive circuit and electronic equipment | |
| CN205900092U (en) | Echo elimination circuit | |
| CN203563026U (en) | Low-pass buffer filter circuit | |
| CN101964936B (en) | Processing chip for digital microphone, input circuit thereof and digital microphone | |
| CN205809757U (en) | Dynamic voltage adjustment device and signal amplifying system | |
| CN105450191A (en) | Dual-line silicon microphone amplifier | |
| CN204993261U (en) | Linear amplifier circuit of on -vehicle audio frequency of single power low -voltage work | |
| CN203120140U (en) | Audio amplification circuit with standby function | |
| CN102832893B (en) | D-type power amplifier | |
| CN204517764U (en) | A kind of enlarge leadingly filter circuit for DIT | |
| CN207166463U (en) | A kind of variable gain audio-frequency amplifier | |
| CN202634678U (en) | Noise-reduction circuit | |
| CN101834574A (en) | Amplifier circuit and method of signal amplification | |
| CN206728280U (en) | A kind of binaural sound amplifying circuit | |
| CN202310028U (en) | Mini microphone | |
| CN204697020U (en) | A kind of dual output constant current-supplying circuit for preamplifier | |
| CN206640735U (en) | A kind of filter circuit of noise cancelling headphone | |
| CN104639070B (en) | Integrated circuit and user terminal |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| C14 | Grant of patent or utility model | ||
| GR01 | Patent grant | ||
| CF01 | Termination of patent right due to non-payment of annual fee |
Granted publication date: 20140423 Termination date: 20201008 |
|
| CF01 | Termination of patent right due to non-payment of annual fee |