CN108769872B - Earphone noise reduction circuit - Google Patents
Earphone noise reduction circuit Download PDFInfo
- Publication number
- CN108769872B CN108769872B CN201810703534.9A CN201810703534A CN108769872B CN 108769872 B CN108769872 B CN 108769872B CN 201810703534 A CN201810703534 A CN 201810703534A CN 108769872 B CN108769872 B CN 108769872B
- Authority
- CN
- China
- Prior art keywords
- circuit
- noise reduction
- audio
- resistor
- noise
- 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.)
- Active
Links
- 230000009467 reduction Effects 0.000 title claims abstract description 81
- 238000001514 detection method Methods 0.000 claims abstract description 16
- 239000003990 capacitor Substances 0.000 claims description 43
- 230000005236 sound signal Effects 0.000 claims description 16
- 230000006854 communication Effects 0.000 claims description 4
- 230000008054 signal transmission Effects 0.000 claims description 4
- 230000003321 amplification Effects 0.000 claims description 3
- 238000003199 nucleic acid amplification method Methods 0.000 claims description 3
- 238000001914 filtration Methods 0.000 claims description 2
- 230000003044 adaptive effect Effects 0.000 abstract description 2
- 238000010586 diagram Methods 0.000 description 12
- 238000000034 method Methods 0.000 description 8
- 230000000087 stabilizing effect Effects 0.000 description 8
- 230000008569 process Effects 0.000 description 6
- 239000000463 material Substances 0.000 description 3
- 230000009471 action Effects 0.000 description 2
- 230000008901 benefit Effects 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 230000000694 effects Effects 0.000 description 2
- 230000008030 elimination Effects 0.000 description 2
- 238000003379 elimination reaction Methods 0.000 description 2
- 230000007613 environmental effect Effects 0.000 description 2
- 238000004891 communication Methods 0.000 description 1
- 210000005069 ears Anatomy 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 230000002452 interceptive effect Effects 0.000 description 1
- 238000004519 manufacturing process Methods 0.000 description 1
- 238000011946 reduction process Methods 0.000 description 1
- 230000001629 suppression Effects 0.000 description 1
- 230000007704 transition Effects 0.000 description 1
Classifications
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/02—Circuits for transducers, loudspeakers or microphones for preventing acoustic reaction, i.e. acoustic oscillatory feedback
Landscapes
- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Soundproofing, Sound Blocking, And Sound Damping (AREA)
- Circuit For Audible Band Transducer (AREA)
Abstract
The invention provides a noise reduction circuit of an earphone, which comprises a signal receiving and transmitting module, a signal receiving and transmitting module and a signal receiving and transmitting module, wherein the signal receiving and transmitting module comprises an antenna and an LC matching circuit; the audio input module comprises an audio input circuit and an audio switching circuit; the audio output module comprises a noise reduction control circuit and an audio output circuit electrically connected with the noise reduction control circuit; the voice input module comprises a voice input signal used for collecting a user; the noise detection module comprises a feedforward input circuit and a feedback input circuit; the signal receiving and transmitting module, the voice input module and the audio output module are electrically connected with the main control chip; the invention controls the audio output module to output sound waves with opposite phases and same frequency and energy with noise detected by the noise detection module through the adaptive operation on the main control chip and the noise detection chip so as to achieve the purpose of eliminating noise.
Description
Technical Field
The invention relates to the technical field of electronic circuits, in particular to a noise reduction circuit of an earphone.
Background
With the continuous development of consumer markets of electronic products, more and more people in daily life use headphones to listen to high-quality music. However, the noise pollution in the city is more and more serious, and the ordinary earphone earplug is used outdoors, and only the volume can be increased to cover the noise, so that not only can wonderful music be enjoyed, but also the hearing of the user is greatly influenced, and people can feel hearing fatigue quickly. At this time, if one wants to calm enjoy the music world, the noise reduction headphones may become the best choice.
In the existing earphone production process, a generally adopted noise elimination mode is passive noise reduction, such as a commercially available earplug, an earmuff and the like. The principle is that the external hard material and the internal filling material are utilized to isolate and absorb noise, so that the noise outside is prevented from entering the ears, and the noise reduction effect on high-frequency noise is more obvious, and the noise suppression method is the most commonly used method at present. However, although this noise reduction is easy to implement, for low frequency noise of 800Hz or lower, a large amount of equipment cost and material weight are required to apply the passive noise reduction, and the passive noise reduction loses practical benefit, and the passive noise reduction suppresses noise and blocks the talking sound of the user, which is one of the main disadvantages of the passive noise reduction.
Disclosure of Invention
Based on this, an object of the present invention is to provide a headset noise reduction circuit employing active noise reduction.
A headset noise reduction circuit, comprising:
The signal receiving and transmitting module comprises an antenna and an LC matching circuit electrically connected with the antenna, and is used for receiving and transmitting signals in the earphone communication process;
the audio input module comprises an audio input circuit and an audio switching circuit electrically connected with the audio input circuit, and is used for acquiring audio signals on the earphone;
the audio output module comprises a noise reduction control circuit and an audio output circuit electrically connected with the noise reduction control circuit, and is used for outputting audio signals on the earphone;
The voice input module comprises a voice input signal used for collecting a user;
The noise detection module comprises a feedforward input circuit and a feedback input circuit and is used for detecting and collecting noise signals of the environment where the earphone is located;
The main control chip is used for correspondingly controlling the transmission of signals on the voice input module and the audio output module according to the on-off state of the noise reduction control circuit;
The noise reduction processing chip is used for correspondingly outputting the suppressed sound waves with opposite phases according to the detection result of the noise detection module.
According to the earphone noise reduction circuit, the main control chip and the noise reduction processing chip are used for adaptively calculating, so that the audio output module is controlled to output sound waves with opposite phases and same frequency and energy with noise detected by the noise detection module, and the purpose of eliminating noise is achieved. Compared with a passive noise reduction mode, the earphone noise reduction circuit performs noise elimination through active noise reduction by overlapping waveforms, namely, noise is combined with a sound wave to be suppressed.
Further, the audio input module comprises an audio input port, a first resistor, a first zener diode, a second zener diode, a first capacitor, a second resistor, a second capacitor and a third resistor, wherein the first resistor, the first zener diode and the second zener diode are respectively electrically connected with the audio input port, the first capacitor and the second resistor are respectively connected with the first zener diode in series, and the second capacitor and the third resistor are respectively connected with the second zener diode in series.
Further, the noise reduction control circuit comprises a fourth resistor, a first triode electrically connected with the fourth resistor, a fifth resistor and a second triode respectively electrically connected with the first triode, and a sixth resistor and a seventh resistor respectively electrically connected with the second triode.
Further, the audio output circuit comprises a horn output port, a third zener diode and a fourth zener diode which are respectively and electrically connected with the horn output port, a third capacitor connected with the third zener diode in series, and a fourth capacitor connected with the fourth zener diode in series.
Further, the voice input module comprises an MIC, a fifth capacitor respectively connected with the MIC in parallel, a sixth capacitor and an eighth resistor respectively connected with the fifth capacitor in series, and a first inductor connected with the sixth capacitor in series.
Further, the main control chip is further provided with a clock circuit and an electric quantity state comparison circuit, the clock circuit provides a clock signal for the main control chip, and the electric quantity state comparison circuit is used for detecting the electric quantity of the battery.
Further, the electric quantity state comparison circuit comprises a third triode, a ninth resistor connected with the third triode in series, a tenth resistor connected with the ninth resistor in series and a seventh capacitor connected with the tenth resistor in series.
Further, a signal amplifying circuit is arranged between the main control chip and the noise reduction processing chip, and the output end of the signal amplifying circuit is electrically connected with the input end of the audio switching circuit.
Further, a memory circuit is further arranged on the main control chip, and the memory circuit comprises a memory unit and an eleventh resistor, a twelfth resistor and a thirteenth resistor which are respectively connected with the memory unit in series.
Further, the main control chip is made of a CSR8635 chip, and the noise reduction processing chip is made of an AMS3435 chip.
Drawings
Fig. 1 is a schematic block diagram of a noise reduction circuit of an earphone according to a first embodiment of the present invention;
fig. 2 is a schematic diagram of a circuit structure among the antenna, LC matching circuit and band-pass filter in fig. 1
FIG. 3 is a schematic diagram of a circuit structure between the Mic circuit and the main control chip in FIG. 1;
FIG. 4 is a schematic diagram of a circuit structure between the filter and switch voltage stabilizing output circuit and the main control chip in FIG. 1;
FIG. 5 is a schematic diagram of a circuit configuration of the L/R audio input circuit of FIG. 1;
FIG. 6 is a schematic circuit diagram of the noise reduction control circuit in FIG. 1;
FIG. 7 is a schematic diagram of the circuit configuration of the L/R horn output circuit of FIG. 1;
FIG. 8 is a schematic diagram of a circuit structure of the memory circuit of FIG. 1;
FIG. 9 is a schematic diagram of the noise reduction chip in FIG. 1;
Fig. 10 is a schematic block diagram of a noise reduction circuit of an earphone according to a second embodiment of the present invention;
FIG. 11 is a schematic diagram of a circuit structure of the state of charge comparing circuit in FIG. 10;
the invention will be further described in the following detailed description in conjunction with the above-described figures.
Detailed Description
In order that the above objects, features and advantages of the invention will be readily understood, a more particular description of the invention will be rendered by reference to the appended drawings. Several embodiments of the invention are presented in the figures. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Rather, these embodiments are provided so that this disclosure will be thorough and complete.
It will be understood that when an element is referred to as being "mounted" on another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. The terms "vertical," "horizontal," "left," "right," "upper," "lower," and the like are used herein for descriptive purposes only and not to indicate or imply that the apparatus or element being referred to must have a particular orientation, be constructed and operated in a particular orientation, and therefore should not be construed as limiting the invention.
In the present invention, unless explicitly specified and limited otherwise, the terms "mounted," "connected," "secured," and the like are to be construed broadly and may be, for example, fixedly connected, detachably connected, or integrally connected; can be mechanically or electrically connected; can be directly connected or indirectly connected through an intermediate medium, and can be communication between two elements. The specific meaning of the above terms in the present invention can be understood by those of ordinary skill in the art according to the specific circumstances. The term "and/or" as used herein includes any and all combinations of one or more of the associated listed items.
Referring to fig. 1 to2 and 9, a first embodiment of the present invention provides an earphone noise reduction circuit 100, which includes:
The signal receiving and transmitting module comprises an antenna 30 and an LC matching circuit 31 electrically connected with the antenna 30, and is used for receiving and transmitting signals in the earphone communication process;
The audio input module comprises an audio input circuit and an audio switching circuit 53 electrically connected with the audio input circuit, wherein the audio input module is used for collecting audio signals on the earphone, and the audio input circuit is an L/R audio input circuit 55 in FIG. 1;
The audio output module comprises a noise reduction control circuit 51 (ANC ON/OFF) and an audio output circuit 54 (L/R horn output) electrically connected with the noise reduction control circuit 51, and is used for outputting audio signals ON the earphone;
A voice input module 40 (Mic circuit) including a voice input signal for collecting a user;
the noise detection module comprises a feedforward input circuit 60 and a feedback input circuit 62, and is used for detecting and collecting noise signals of the environment where the earphone is located;
The main control chip 10 is made of a CSR8635 chip, the signal receiving and transmitting module, the voice input module 40 and the audio output module are electrically connected with the main control chip 10, and the main control chip 10 is used for correspondingly controlling the transmission of signals on the voice input module 40 and the audio output module according to the on-off state of the noise reduction control circuit 51;
The noise reduction processing chip 50, the noise reduction processing chip 50 is made of an AMS3435 chip, the main control chip 10, the audio input module, the audio output module and the noise detection module are all electrically connected with the noise reduction processing chip 50, and the noise reduction processing chip 50 is configured to output the suppressed sound waves with opposite phases according to the detection result of the noise detection module.
Specifically, referring to fig. 3, the voice input module 40 includes a MIC, a fifth capacitor C17 connected in parallel with the MIC, a sixth capacitor C16 and an eighth resistor R12 connected in series with the fifth capacitor C17, and a first inductor L6 connected in series with the sixth capacitor C16, where the MIC is a microphone, the MIC is used for identifying a voice signal of a front end user, so that a subsequent voice transmission step in the earphone is effectively facilitated, and preferably, in this embodiment, a VCC pin of the MIC is electrically connected with the eighth resistor R12, a G pin of the MIC is connected in series with the sixth capacitor C16 and the fifth capacitor C17, respectively, a resistance value of the eighth resistor R12 is 2.2K, a capacity of the fifth capacitor C17 is 1uf, a capacity of the sixth capacitor is 15p, and a value of the first inductor L6 is 15nH.
Referring to fig. 4 to 5, the main control chip 10 is further provided with a filter and switch voltage stabilizing output circuit, the audio input module includes an audio input port J17, a first resistor R60, a first voltage stabilizing diode VR5 and a second voltage stabilizing diode VR6, a first capacitor C136 and a second resistor R4 respectively connected in series with the first voltage stabilizing diode, a second capacitor C137 and a third resistor R3 respectively connected in series with the second voltage stabilizing diode, the resistance of the first resistor R60 is 100R, the resistance of the second resistor R4 is 150R, the resistance of the third resistor R3 is 150R, the capacities of the first capacitor C136 and the second capacitor C137 are 33p, and the output ends of the first voltage stabilizing diode VR5, the second voltage stabilizing diode VR6, the first capacitor C136, the second capacitor C137, the second resistor R4 and the third resistor R3 are all connected with the ground.
Referring to fig. 6, the noise reduction control circuit 51 includes a fourth resistor R1, a first triode Q3 electrically connected to the fourth resistor R4, a fifth resistor R2 and a second triode Q2 electrically connected to the first triode Q3 respectively, and a sixth resistor R61 and a seventh resistor R13 electrically connected to the second triode Q2 respectively, wherein the resistance of the fourth resistor R1 is 10K, the resistance of the fifth resistor R2 is 47K, the resistance of the sixth resistor R61 is 300K, and the resistance of the seventh resistor R13 is 100K.
Referring to fig. 7, the audio output circuit includes a speaker output port, a third zener diode VR3 and a fourth zener diode VR4 electrically connected to the speaker output port, a third capacitor C24 connected in series with the third zener diode VR3, and a fourth capacitor C25 connected in series with the fourth zener diode VR4, where the capacities of the third capacitor C24 and the fourth capacitor are 10nF, and specifically, in this embodiment, the speaker output port includes an anode port J28 and a cathode port J19, and the speaker output port is used for outputting voice on the earphone.
In addition, in this embodiment, a signal amplifying circuit 52 (BT amplifying circuit) is disposed between the main control chip 10 and the noise reduction processing chip 50, an output end of the signal amplifying circuit 52 is electrically connected to an input end of the audio switching circuit 53, and the signal amplifying circuit 52 is configured to amplify a signal sent by the main control chip 10 toward the noise reduction processing chip 50, so as to improve stability of signal transmission.
Referring to fig. 8, a memory circuit 41 is further disposed on the main control chip 10, the memory circuit 41 includes a memory cell and an eleventh resistor R5, a twelfth resistor R6 and a thirteenth resistor R7 respectively connected in series with the memory cell, the memory cell is made of a 24C512A chip, resistance values of the eleventh resistor R5, the twelfth resistor R6 and the thirteenth resistor R7 are all 2.2K, and the eleventh resistor R5, the twelfth resistor R6 and the thirteenth resistor R7 are all connected in series with an eighth capacitor C26, and a capacity of the eighth capacitor C26 is 10nF.
Preferably, in this embodiment, the WC pin of the memory cell is connected in series with the eleventh resistor R5, the SCL pin of the memory cell is connected in series with the twelfth resistor R6, and the SDA pin of the memory cell is connected in series with the thirteenth resistor R7
Specifically, the usage flow of this embodiment is that the call receiving process: after the earphone is started, a power supply supplies power to the main control chip 10, after the terminal equipment and the host are matched in an interactive way, the opposite party calls the terminal equipment, signals are sent out and received by the signal receiving and transmitting module, the signals are processed by the main control chip 10, and if noise reduction ANC is OFF, the signals are output through the ESD protection circuit and the loudspeaker.
If the noise reduction ANC is ON, the signal is amplified by the BT amplifying circuit 52, is processed by the L/R audio frequency and BT switching to the noise reduction processor chip 50, and then the external environmental noise is detected in parallel by the feedforward input circuit 60 and is transmitted to the noise reduction processor chip 50, and is processed by the internal inverting amplifier and different RC filter networks, and then is superimposed to the loudspeaker with the required audio signal by the ESD protection circuit, so that the phase cancellation of the environmental noise is completed, and the feedforward noise reduction process is realized. Meanwhile, after the feedback input circuit 62 detects the noise output by the loudspeaker and processes the noise by the inverting amplifier and different RC filter networks in the noise reduction processor chip 50, the noise is mixed with the required audio signal by the ESD protection circuit and is superimposed on the loudspeaker to be phase-offset, so that the purpose of noise reduction is achieved, and the conversation listening process is completed.
And (3) a call sending process: after the earphone is started, a power supply supplies power to the main control chip 10, after the pickup MIC picks up a required audio signal, the audio signal is transmitted to the main control chip 10 for processing after passing through a filtering and anti-interference circuit, and is provided with a network circuit and an antenna for transmitting to terminal equipment through the band-pass filter 32, so that the telephone transmission process is completed.
Listening process: the L/R audio circuit inputs audio signals, the audio signals enter the noise reduction processor chip through the switch circuit (L/R audio and BT switch), and at the moment, if the ANC is closed, the audio signals are output from the L/R loudspeaker after passing through the anti-interference circuit.
If ANC ON, after the signal passes through the ESD anti-interference protection circuit, the signal is switched to the noise reduction processor chip for processing through the L/R audio frequency and BT, the parallel feedback module detects the noise signal output by the loudspeaker to the inverting amplifier in the noise reduction processor chip for phase processing and signal amplification, and after the signal is processed through different RC filter networks, the signal is overlapped to the loudspeaker through the ESD protection circuit together with the required audio signal, so that the noise from the signal and the inverse phase noise signal detected by the feedback module are mixed and overlapped, the noise reduction purpose is achieved, and the listening process is completed.
Preferably, the earphone noise reduction circuit 100 further includes an instruction control circuit 34, where the instruction control circuit 34 is configured to interact with software and send an instruction to the main control chip 10, so as to implement functions of volume+, volume-and-on/off, answering a call, terminating a call, playing music, etc. for the user.
The earphone noise reduction circuit 100 further includes an LED circuit 22 for providing different display states for different instructions and states under the action of the software and the main control chip 10.
The earphone noise reduction circuit 100 further comprises a power module 20 for charging the battery via the main control chip 10 and providing overvoltage protection, and when the main control chip 10 detects that the voltage is full, a signal is fed back to the power circuit to stop charging and instruct the LED circuit 22 to display state transition. If the external voltage rises due to a certain factor, the overvoltage protection of the power supply part plays a key role, so that the host is protected, and the potential safety hazard is eliminated.
The earphone noise reduction circuit 100 controls the audio output module to output sound waves with opposite phases and same frequency and energy with the noise detected by the noise detection module through the adaptive operation on the main control chip 10 and the noise reduction processing chip 50, so as to achieve the purpose of eliminating noise. Compared with the passive noise reduction mode, the earphone noise reduction circuit 100 performs noise reduction by adopting active noise reduction and overlapping waveforms, that is, the noise is combined with the suppressed sound wave, and if the waveform of the suppressed wave is the same as the amplitude and frequency of the sound wave to be silenced, and the waveform is opposite to the frequency, the noise reduction effect is obtained.
Referring to fig. 10, a schematic block diagram of a headset noise reduction circuit 100a according to a second embodiment of the present invention is provided, and the second embodiment has substantially the same structure as the first embodiment, wherein in the present embodiment, a clock circuit 21 and a state of charge comparison circuit 33 are further provided on the main control chip 10, the clock circuit 21 provides a clock signal for the main control chip 10, and the state of charge comparison circuit 33 is configured to detect the battery power under the action of the main control chip 10 and indicate the state of the LED, and meanwhile, the main control chip 10 issues an instruction to perform a status quotation.
Specifically, referring to fig. 11, a schematic circuit structure of the state of charge comparing circuit 33 in fig. 10 is shown, the state of charge comparing circuit includes a third triode Q1, a ninth resistor R10 connected in series with the third triode Q1, a tenth resistor R126 connected in series with the ninth resistor R10, and a seventh capacitor C149 connected in series with the tenth resistor R126, the model of the third triode Q1 is BCX51, the resistance value of the ninth resistor R10 is 400mR, the resistance value of the tenth resistor R126 is 200mR, the capacity of the seventh capacitor C149 is 15p, and the output end of the seventh capacitor C149 is connected with the ground.
The above embodiments describe the technical principle of the present invention, and these descriptions are only for explaining the principle of the present invention and should not be construed in any way as limiting the scope of the present invention. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the invention disclosed herein, without departing from the spirit and scope of the invention.
Claims (6)
1. A headset noise reduction circuit, comprising:
The signal receiving and transmitting module comprises an antenna and an LC matching circuit electrically connected with the antenna, and is used for receiving and transmitting signals in the earphone communication process;
the audio input module comprises an audio input circuit and an audio switching circuit electrically connected with the audio input circuit, and is used for acquiring audio signals on the earphone;
the audio output module comprises a noise reduction control circuit and an audio output circuit electrically connected with the noise reduction control circuit, and is used for outputting audio signals on the earphone;
The voice input module comprises a voice input signal used for collecting a user;
The noise detection module comprises a feedforward input circuit and a feedback input circuit and is used for detecting and collecting noise signals of the environment where the earphone is located;
The main control chip is used for correspondingly controlling the transmission of signals on the voice input module and the audio output module according to the on-off state of the noise reduction control circuit;
The noise reduction processing chip comprises an inverting amplifier and a band-pass filter, the main control chip, the audio input module, the audio output module and the noise detection module are electrically connected with the noise reduction processing chip, the noise reduction processing chip is used for correspondingly outputting sound waves with opposite phases and the same frequency and energy according to the detection result of the noise detection module, and a BT amplifying circuit is arranged between the control chip and the noise reduction processing chip;
the voice input module comprises an MIC, a fifth capacitor respectively connected with the MIC in parallel, a sixth capacitor and an eighth resistor respectively connected with the fifth capacitor in series, and a first inductor connected with the sixth capacitor in series;
The noise reduction control circuit comprises a fourth resistor, a first triode electrically connected with the fourth resistor, a fifth resistor and a second triode respectively electrically connected with the first triode, and a sixth resistor and a seventh resistor respectively electrically connected with the second triode;
the audio output circuit comprises a horn output port, a third zener diode, a fourth zener diode, a third capacitor and a fourth capacitor, wherein the third zener diode and the fourth zener diode are respectively electrically connected with the horn output port;
The main control chip is also provided with a clock circuit and an electric quantity state comparison circuit, the clock circuit provides a clock signal for the main control chip, and the electric quantity state comparison circuit is used for detecting the electric quantity of the battery;
When receiving a call, if ANC is OFF, outputting a signal through an ESD protection circuit through a loudspeaker, and if ANC is ON, performing phase cancellation ON external noise through the feedforward input circuit and the feedback input circuit;
when a call is sent, after the MIC picks up an audio signal, the MIC is sequentially processed by a filtering wave and anti-interference circuit, a main control chip and a band-pass filter;
When listening, if ANC OFF, audio signal is after L/R audio frequency & BT switches over, falls the processor chip of making an uproar in proper order, export from L/R loudspeaker, if ANC ON, carry out the phase place offset to L/R loudspeaker output signal through the feedback input circuit.
2. The earphone noise reduction circuit according to claim 1, wherein the audio input module comprises an audio input port, a first resistor, a first zener diode, a second zener diode, a first capacitor and a second resistor connected in series with the first zener diode, and a second capacitor and a third resistor connected in series with the second zener diode.
3. The earphone noise reduction circuit according to claim 1, wherein the state of charge comparison circuit comprises a third triode, a ninth resistor in series with the third triode, a tenth resistor in series with the ninth resistor, and a seventh capacitor in series with the tenth resistor.
4. The earphone noise reduction circuit according to claim 1, wherein a signal amplification circuit is arranged between the main control chip and the noise reduction processing chip, and an output end of the signal amplification circuit is electrically connected with an input end of the audio switching circuit.
5. The earphone noise reduction circuit according to claim 1, wherein a memory circuit is further provided on the main control chip, and the memory circuit includes a memory cell and eleventh, twelfth and thirteenth resistors respectively connected in series with the memory cell.
6. The earphone noise reduction circuit according to claim 1, wherein the main control chip is made of a CSR8635 chip, and the noise reduction processing chip is made of an AMS3435 chip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810703534.9A CN108769872B (en) | 2018-06-29 | 2018-06-29 | Earphone noise reduction circuit |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810703534.9A CN108769872B (en) | 2018-06-29 | 2018-06-29 | Earphone noise reduction circuit |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN108769872A CN108769872A (en) | 2018-11-06 |
| CN108769872B true CN108769872B (en) | 2024-06-21 |
Family
ID=63975248
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201810703534.9A Active CN108769872B (en) | 2018-06-29 | 2018-06-29 | Earphone noise reduction circuit |
Country Status (1)
| Country | Link |
|---|---|
| CN (1) | CN108769872B (en) |
Families Citing this family (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110300344B (en) * | 2019-03-25 | 2024-06-14 | 深圳市增长点科技有限公司 | Self-adaptive noise reduction earphone |
| CN110418238A (en) * | 2019-08-21 | 2019-11-05 | 深圳市昂思科技有限公司 | A kind of noise reduction bluetooth headset |
| CN110784238A (en) * | 2019-09-26 | 2020-02-11 | 常熟市欧伏罱电子有限公司 | Circuit structure of earplug interphone |
| CN113824470A (en) * | 2021-09-26 | 2021-12-21 | 海南宝通实业公司 | Method and device for improving frequency hopping receiving voice quality |
| CN118629384A (en) * | 2024-08-08 | 2024-09-10 | 厦门立林科技有限公司 | Noise reduction method, intelligent household equipment and system |
Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103686501A (en) * | 2012-09-05 | 2014-03-26 | 深圳市凯聚源科技有限公司 | Noise cancelling bluetooth headset |
| CN106937194A (en) * | 2015-12-30 | 2017-07-07 | Gn奥迪欧有限公司 | With the headphone and its operating method of listening logical pattern |
| CN208353567U (en) * | 2018-06-29 | 2019-01-08 | 江西联创宏声电子股份有限公司 | Earphone Dolby circuit |
Family Cites Families (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US20130108068A1 (en) * | 2011-10-27 | 2013-05-02 | Research In Motion Limited | Headset with two-way multiplexed communication |
| CN107517415B (en) * | 2016-06-16 | 2024-06-07 | 江西斐耳科技有限公司 | Intelligent earphone |
| CN108063996B (en) * | 2018-01-24 | 2024-10-11 | 江西联创宏声万安电子有限公司 | Type C interface earphone and implementation method thereof |
-
2018
- 2018-06-29 CN CN201810703534.9A patent/CN108769872B/en active Active
Patent Citations (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN103686501A (en) * | 2012-09-05 | 2014-03-26 | 深圳市凯聚源科技有限公司 | Noise cancelling bluetooth headset |
| CN106937194A (en) * | 2015-12-30 | 2017-07-07 | Gn奥迪欧有限公司 | With the headphone and its operating method of listening logical pattern |
| CN208353567U (en) * | 2018-06-29 | 2019-01-08 | 江西联创宏声电子股份有限公司 | Earphone Dolby circuit |
Also Published As
| Publication number | Publication date |
|---|---|
| CN108769872A (en) | 2018-11-06 |
Similar Documents
| Publication | Publication Date | Title |
|---|---|---|
| CN108769872B (en) | Earphone noise reduction circuit | |
| CN104521247B (en) | Bluetooth headset hearing aid and anti-noise method and apparatus | |
| CN104935742B (en) | Communication terminal and the method for improving its tonequality under handset mode | |
| CN202587132U (en) | Voice call circuit with echo suppression function and flat panel computer | |
| US20150139428A1 (en) | Apparatus with a speaker used as second microphone | |
| CN201197140Y (en) | Wireless playing headphone | |
| JP2010527541A (en) | Communication device with ambient noise reduction function | |
| CN101742383B (en) | Device and method for eliminating plosives of headset | |
| CN207744142U (en) | A kind of multi-functional bone conduction hearing aid system | |
| CN202872884U (en) | Audio output circuit and mobile terminal | |
| CN206713019U (en) | Active noise reducing device and earphone | |
| CN203909716U (en) | Novel mind headset | |
| CN202841470U (en) | Noise-canceling headphones | |
| CN104581515B (en) | A kind of audio playing apparatus, method and mobile terminal | |
| CN107770662A (en) | A kind of automatic charging and the implementation method and circuit of switching on and shutting down | |
| CN106550074A (en) | A kind of improved structure of combination earpiece loudspeaker | |
| CN107864415A (en) | Audio amplifier and audio frequency apparatus share the control method and device of microphone | |
| KR101045965B1 (en) | Uses the grade signal of the speaker echo actual condition removal technique of the microphone phone | |
| CN203968327U (en) | A kind of exempt from extract carry out low coverage dialogue earphone | |
| CN101437183B (en) | Earplug type bone conduction receiver-transmitter | |
| CN207443128U (en) | A kind of mobile terminal with hearing-aid function | |
| CN208353567U (en) | Earphone Dolby circuit | |
| CN203151729U (en) | Multifunctional earphone | |
| CN207340110U (en) | Earphone with outer playing function | |
| CN205195931U (en) | Headset |
Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PB01 | Publication | ||
| PB01 | Publication | ||
| SE01 | Entry into force of request for substantive examination | ||
| SE01 | Entry into force of request for substantive examination | ||
| GR01 | Patent grant | ||
| GR01 | Patent grant |