CN108810740B - Audio signal transmission device and electronic equipment - Google Patents
Audio signal transmission device and electronic equipment Download PDFInfo
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- CN108810740B CN108810740B CN201810587856.1A CN201810587856A CN108810740B CN 108810740 B CN108810740 B CN 108810740B CN 201810587856 A CN201810587856 A CN 201810587856A CN 108810740 B CN108810740 B CN 108810740B
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- 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
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Abstract
The embodiment of the invention discloses an audio signal transmission device and electronic equipment. The device comprises an isolation circuit, a voltage reduction circuit, a microphone and a coupling circuit; the input end of the isolation circuit is electrically connected with the power supply signal power supply channel and is used for isolating interference signals included in the input power supply signals to obtain standard voltage signals; the input end of the voltage reduction circuit is electrically connected with the output end of the isolation circuit and is used for adjusting the input standard voltage signal into a standard voltage reduction signal matched with the microphone; the power input end of the microphone is electrically connected with the output end of the voltage reduction circuit and is used for collecting sound under the trigger of an input standard voltage reduction signal and converting the sound into a voice signal; the input end of the coupling circuit is electrically connected with the output end of the microphone and used for outputting the voice signal received by coupling to the power supply signal power supply channel. The embodiment of the invention can improve the anti-interference capability of audio signal transmission.
Description
Technical Field
The present invention relates to circuit technologies, and in particular, to an audio signal transmission device and an electronic device.
Background
Along with the development of science and technology, the demand of the sound interaction function of the intelligent equipment is more and more large, for example, in the fields of intelligent home, intelligent terminals and the like.
At present, smart machine's miniaturization integrates the demand higher, and the space of placing smart machine is less, and smart machine has multiple functions again simultaneously, and consequently under this kind of environment, smart machine is higher to quantity of pencil, the cost of pencil and volume requirement. In this scenario, the audio signal is transmitted by providing a voltage matched with a Microphone (MIC) through a voltage reduction circuit, and coupling the audio signal to a dc power signal for output. However, the transmission circuit cannot solve the problem of interference caused by multi-line and dense power line layout to the audio signal when the audio signal is superimposed on the direct-current power supply, and the output abnormal output of the MIC is caused by the fact that the output of the MIC is interfered by overlarge output audio signal, so that the amplitude of audio output is very small, the anti-interference capability is poor, and the requirement for high-amplitude audio signals cannot be met.
Disclosure of Invention
The embodiment of the invention provides an audio signal transmission device and electronic equipment, which can improve the anti-interference capacity of audio signal transmission.
In a first aspect, an embodiment of the present invention provides an audio signal transmission apparatus, where the transmission apparatus includes an isolation circuit, a voltage reduction circuit, a microphone, and a coupling circuit;
the input end of the isolation circuit is electrically connected with the power supply signal power supply channel and is used for isolating interference signals included in the input power supply signals to obtain standard voltage signals;
the input end of the voltage reduction circuit is electrically connected with the output end of the isolation circuit and is used for adjusting the input standard voltage signal into a standard voltage reduction signal matched with the microphone;
the power supply input end of the microphone is electrically connected with the output end of the voltage reduction circuit and is used for collecting sound under the triggering of the input standard voltage reduction signal and converting the sound into a voice signal;
the input end of the coupling circuit is electrically connected with the output end of the microphone and is used for outputting the voice signal received by coupling to the power supply signal power supply channel.
Optionally, the apparatus further includes: the input end of the filter circuit is electrically connected with the output end of the isolation circuit, and the output end of the filter circuit is electrically connected with the input end of the voltage reduction circuit;
the filter circuit is used for filtering the standard voltage signal output by the isolation circuit and inputting the filtered signal to the voltage reduction circuit.
Optionally, the voltage dropping circuit includes: a low voltage linear regulator.
Optionally, the apparatus further includes: the input end of the amplifying circuit is electrically connected with the output end of the microphone, and the output end of the amplifying circuit is electrically connected with the input end of the coupling circuit;
the amplifying circuit is used for amplifying the voice signal output by the microphone and inputting the amplified voice signal to the coupling circuit.
Optionally, the amplifying circuit specifically includes: an operational amplifier;
the signal input end of the operational amplifier is electrically connected with the output end of the microphone, and the signal output end of the operational amplifier is electrically connected with the input end of the coupling circuit.
Optionally, the output end of the voltage reduction circuit is electrically connected with the power input end of the operational amplifier;
the voltage reduction circuit is further configured to: and supplying power to the operational amplifier so that the maximum output voltage of the operational amplifier is equal to the output voltage of the voltage reduction circuit.
Optionally, the operational amplifier is specifically a rail-to-rail operational amplifier.
In a second aspect, an embodiment of the present invention further provides an electronic device, including the apparatus for transmitting an audio signal according to the embodiment of the present invention.
According to the embodiment of the invention, the isolation circuit is arranged between the power supply and the voltage reduction circuit, and the interference signal of the power supply is isolated at the input end of the voltage reduction circuit, so that the voltage signal for reducing the power supply interference is input into the microphone through the voltage reduction circuit, then is input into the coupling circuit through the microphone, is finally superposed into the power supply through the coupling circuit, and is isolated from the input signal of the coupling circuit again, thereby reducing the interference of the power supply signal in the whole circuit and improving the anti-interference capability of the whole circuit.
Drawings
Fig. 1 is a schematic structural diagram of an audio signal transmission apparatus according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a voltage step-down circuit according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of an apparatus for transmitting an audio signal according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of an electronic device according to an embodiment of the present invention.
Detailed Description
The present invention will be described in further detail with reference to the accompanying drawings and examples. It is to be understood that the specific embodiments described herein are merely illustrative of the invention and are not limiting of the invention. It should be further noted that, for the convenience of description, only some of the structures related to the present invention are shown in the drawings, not all of the structures.
Example one
Fig. 1 is a schematic structural diagram of an audio signal transmission apparatus according to an embodiment of the present invention, which is applicable to a situation where a microphone is used in a dc circuit with a high integration level to transmit an audio signal, and as shown in fig. 1, the specific structure of the audio signal transmission apparatus is as follows:
an audio signal transmission device 110 includes an isolation circuit 120, a voltage reduction circuit 130, a microphone 140, and a coupling circuit 150.
The input end of the isolation circuit 120 is electrically connected to the power supply channel 100 for isolating an interference signal included in the input power supply signal to obtain a standard voltage signal;
the input end of the voltage-reducing circuit 130 is electrically connected to the output end of the isolating circuit 120, and is used for adjusting the input standard voltage signal into a standard voltage-reducing signal matched with the microphone 140;
the power input end of the microphone 140 is electrically connected with the output end of the voltage reduction circuit 130, and is used for collecting sound under the triggering of an input standard voltage reduction signal and converting the sound into a voice signal;
an input terminal of the coupling circuit 150 is electrically connected to an output terminal of the microphone 140, and is configured to output the voice signal received by coupling to the power signal supply channel 100.
According to the embodiment of the invention, the isolation circuit is arranged between the power supply and the voltage reduction circuit, and the interference signal of the power supply is isolated at the input end of the voltage reduction circuit, so that the voltage signal for reducing the power supply interference is input into the microphone through the voltage reduction circuit, then is input into the coupling circuit through the microphone, is finally superposed into the power supply through the coupling circuit, and is isolated from the input signal of the coupling circuit again, thereby reducing the interference of the power supply signal in the whole circuit and improving the anti-interference capability of the whole circuit.
The input end of the isolation circuit 120 is electrically connected to the power supply channel 100, and is configured to isolate an interference signal included in the input power supply signal, so as to obtain a standard voltage signal.
Optionally, the power signal supply channel 100 may receive a power signal output by a power source, and is configured to output the power signal for the transmission device 110 of the audio signal, and may have a plurality of output ports, each of which is capable of outputting the power signal for simultaneously supplying power to a plurality of electrical components, and specifically may include a dc power signal supply channel that provides a dc power signal for the isolation circuit 120. The isolation circuit 120 is used to isolate the interference signal from the power signal, thereby reducing power supply interference experienced by the microphone output audio signal. The reference voltage signal may be a voltage signal output by the isolation circuit that has been partially power disturbance removed. Wherein, the isolation circuit 120 may include a photoelectric coupling basic device, specifically, a light emitting element (light emitting diode) and a photosensitive element (phototriode), in an optional example, the light emitting element is located in the input loop, the light emitting element converts a power signal output by the dc power supply into an optical signal, the photosensitive element is located in the output loop, the photosensitive element converts the sensed optical signal into an electrical signal for output, thereby avoiding the direct electrical connection between the power supply and the microphone, and realizing the electrical isolation of the two circuits, thereby effectively suppressing the power supply interference, and simultaneously, also cutting off the interference of the audio signal output by the microphone to the subsequent power supply loop.
The input terminal of the voltage dropping circuit 130 is electrically connected to the output terminal of the isolation circuit 120, and is used for adjusting the input standard voltage signal into a standard dropped signal matched with the microphone 140.
Optionally, the voltage dropping circuit 130 is configured to drop and output the input voltage. Generally, the power supply voltage is higher than the operating voltage of the microphone, and thus, the voltage reduction circuit is provided to reduce the power supply voltage to a voltage equal to the operating voltage of the microphone, i.e., the voltage value of the standard voltage reduction signal may be equal to the operating voltage of the microphone. As shown in fig. 2, the voltage-reducing circuit 130 may include a switch 210 (which may be a metal oxide semiconductor field effect transistor or an insulated gate bipolar transistor), an inductor 220, and a diode 230, where when the switch 210 is closed, the diode is open, the inductor is charged, and the power supply supplies power to the load; when the switch is turned off, the diode plays a role of follow current, the inductor discharges and enables the current value flowing through the circuit to be equal to the current value when the switch is turned off, the voltage at the left end of the inductor is zero, the diode and the load divide the voltage, the voltage at two ends of the load is reduced, and the actually output voltage is the duty ratio of the input voltage multiplied by the pulse width modulated square wave.
Optionally, the step-down circuit 130 includes a low dropout regulator (LDO), which generally has very low inherent noise and a high power supply rejection ratio, and is used to stabilize the output voltage at a set value, thereby improving the interference immunity of the circuit and increasing the power supply utilization ratio.
The power input terminal of the microphone 140 is electrically connected to the output terminal of the voltage-reducing circuit 130, and is configured to collect sound triggered by an input standard voltage-reducing signal and convert the sound into a voice signal.
Optionally, the voltage-reducing circuit 130 provides a standard voltage-reducing signal to the microphone 140 so that the microphone 140 can work normally. The microphone 140 may be a device that converts sound into an electrical signal, for example, an electret microphone, and when an electret diaphragm senses sound waves (vibration), the distance between metal plates changes, and further, an electric field across a capacitor changes, so as to generate an alternating voltage, which is a voice signal.
An input terminal of the coupling circuit 150 is electrically connected to an output terminal of the microphone 140, and is configured to output the coupled and received voice signal to the power supply channel 100.
Optionally, the coupling circuit 150 extracts a valid signal from the voice signal output from the microphone 140 and outputs the valid signal to the power supply loop. The coupling circuit 150 may include only a capacitor, may include an opto-coupler, specifically, a light emitting element (e.g., a light emitting diode) and a photosensitive element (e.g., a phototransistor), or may include a transformer coupling circuit. In an optional example, the coupling circuit 150 is specifically a capacitor, the capacitor has functions of blocking direct current and passing alternating current, a voice signal (i.e., an alternating current signal) can be input into the power supply channel 100 through the capacitor, and meanwhile, other direct current interference signals cannot pass through the capacitor, so that the purposes of extracting the voice signal and reducing interference signals are achieved.
It should be noted that the isolation circuit 120, the voltage reduction circuit 130, the microphone 140, and the coupling circuit 150 may be selected according to actual needs, and the embodiment is not limited thereto.
According to the technical scheme, the isolation circuit is arranged between the power supply and the voltage reduction circuit, the problem that power supply interference is large in the audio transmission circuit in the prior art is solved, and the anti-interference capacity of audio signal transmission is improved.
As shown in fig. 3, in an alternative embodiment of the present invention, the audio signal transmission device 310 includes an isolation circuit 120, a voltage reduction circuit 130, a microphone 140, a coupling circuit 150, a filter circuit 160, and an amplification circuit 170.
The input end of the isolation circuit 120 is electrically connected to the power supply channel 100, and is configured to isolate an interference signal included in the input power supply signal, so as to obtain a standard voltage signal.
The input end of the filter circuit 160 is electrically connected to the output end of the isolation circuit 120, the output end of the filter circuit 160 is electrically connected to the input end of the voltage-reducing circuit 160, and the filter circuit 160 is configured to filter the standard voltage signal output by the isolation circuit 120 and input the filtered signal to the voltage-reducing circuit 130.
Alternatively, the filter circuit 160 may employ a reactive element (e.g., a capacitor or an inductor) having an energy storage function to filter an ac component in the signal output by the isolation circuit to obtain a dc signal. The filter circuit can be passive filter (such as capacitance filter, inductance filter, complex filter (such as inductance and capacitance combined filter) and active filter (such as resistance and capacitance combined filter).
The input terminal of the voltage dropping circuit 130 is electrically connected to the output terminal of the filter circuit 160, and is used for adjusting the input standard voltage signal into a standard dropped signal matched with the microphone 140.
The power input terminal of the microphone 140 is electrically connected to the output terminal of the voltage-reducing circuit 130, and is configured to collect sound triggered by an input standard voltage-reducing signal and convert the sound into a voice signal.
The input end of the amplifying circuit 170 is electrically connected to the output end of the microphone 140, and the output end of the amplifying circuit 170 is electrically connected to the input end of the coupling circuit 150, and is configured to amplify the voice signal output by the microphone 140 and input the amplified voice signal to the coupling circuit 150.
Alternatively, the amplifying circuit 170 may output a signal with an undistorted waveform and an increased amplitude by receiving the small signal. The amplifying circuit 170 generally includes a triode, a field effect transistor, and may specifically include an operational amplifier, wherein a signal input terminal of the operational amplifier is electrically connected to the output terminal of the microphone 140, and a signal output terminal of the operational amplifier is electrically connected to the input terminal of the coupling circuit 150.
Alternatively, the amplifying circuit 170 may be composed of a plurality of operational amplifiers. By adopting the amplifying circuit, the output amplitude of the voice signal can be improved, and the utilization rate of the power supply can be improved.
Optionally, the amplifying circuit 170 includes an operational amplifier, and may be a rail-to-rail (rail-to-rail) operational amplifier. By adopting the rail-to-rail operational amplifier, the maximum output voltage of the amplifying circuit can reach the power supply voltage of the rail-to-rail operational amplifier, namely, the voice signal is amplified to the maximum extent, so that the amplitude of the output audio signal is increased, the energy of the power supply is fully utilized, and the utilization rate of the power supply is improved.
It should be noted that the filter circuit 160, the amplifying circuit 170 and the operational amplifier can be selected according to actual needs, and the embodiment is not limited.
Optionally, the output terminal of the voltage-reducing circuit 130 is electrically connected to the power input terminal of the operational amplifier; the voltage dropping circuit 130 is further configured to: the operational amplifier is powered such that the maximum output voltage of the operational amplifier is equal to the output voltage of the voltage dropping circuit 130. Optionally, the voltage-reducing circuit 130 is used to supply power to the operational amplifier, so that the output voltage of the operational amplifier reduces the loss of the voice signal in the signal transmission process to the greatest extent, the amplitude of the voice signal is greatly increased, and the subsequent signal processing is facilitated.
The input terminal of the coupling circuit 150 is electrically connected to the output terminal of the amplifying circuit 170, and is configured to output the coupled and amplified voice signal to the power supply channel 100.
By further adopting the filter circuit and the amplifying circuit to realize audio signal transmission, the anti-jamming capability of the audio signal transmission can be improved, the amplitude of the output audio signal is increased, and the utilization rate of a power supply is improved.
The transmission device of audio signals provided in this embodiment can be applied to electronic equipment. As shown in fig. 4, the electronic device 410 further includes a transmission device 420 for audio signals and a power supply 430, where the power supply 430 supplies power to the transmission device 420 for audio signals, and the transmission device 420 for audio signals may be any one of the transmission devices for audio signals provided in this embodiment.
It is noted that the foregoing is only illustrative of some embodiments of the invention and the technical principles employed. It will be understood by those skilled in the art that the present invention is not limited to the particular embodiments illustrated herein, but is capable of various obvious changes, rearrangements and substitutions as will now become apparent to those skilled in the art without departing from the scope of the invention. Therefore, although the present invention has been described in greater detail by the above embodiments, the present invention is not limited to the above embodiments, and may include other equivalent embodiments without departing from the spirit of the present invention, and the scope of the present invention is determined by the scope of the appended claims.
Claims (8)
1. The transmission device of the audio signal is characterized in that the transmission device of the audio signal is configured in a miniaturized intelligent device and comprises an isolation circuit, a voltage reduction circuit, a microphone and a coupling circuit;
the input end of the isolation circuit is electrically connected with the direct-current power supply signal power supply channel and is used for isolating interference signals included in the input direct-current power supply signals to obtain standard voltage signals;
the input end of the voltage reduction circuit is electrically connected with the output end of the isolation circuit and is used for adjusting the input standard voltage signal into a standard voltage reduction signal matched with the microphone;
the power supply input end of the microphone is electrically connected with the output end of the voltage reduction circuit and is used for collecting sound under the triggering of the input standard voltage reduction signal and converting the sound into a voice signal;
the input end of the coupling circuit is electrically connected with the output end of the microphone and used for outputting the voice signal received by coupling to the direct-current power supply signal power supply channel.
2. The apparatus of claim 1, further comprising: the input end of the filter circuit is electrically connected with the output end of the isolation circuit, and the output end of the filter circuit is electrically connected with the input end of the voltage reduction circuit;
the filter circuit is used for filtering the standard voltage signal output by the isolation circuit and inputting the filtered signal to the voltage reduction circuit.
3. The apparatus of claim 1, wherein the voltage-reduction circuit comprises: a low voltage linear regulator.
4. The apparatus of any of claims 1-3, further comprising: the input end of the amplifying circuit is electrically connected with the output end of the microphone, and the output end of the amplifying circuit is electrically connected with the input end of the coupling circuit;
the amplifying circuit is used for amplifying the voice signal output by the microphone and inputting the amplified voice signal to the coupling circuit.
5. The apparatus according to claim 4, wherein the amplifying circuit comprises in particular: an operational amplifier;
the signal input end of the operational amplifier is electrically connected with the output end of the microphone, and the signal output end of the operational amplifier is electrically connected with the input end of the coupling circuit.
6. The apparatus of claim 5, wherein: the output end of the voltage reduction circuit is electrically connected with the power supply input end of the operational amplifier;
the voltage reduction circuit is further configured to: and supplying power to the operational amplifier so that the maximum output voltage of the operational amplifier is equal to the output voltage of the voltage reduction circuit.
7. The apparatus of claim 5, wherein the operational amplifier is specifically a rail-to-rail operational amplifier.
8. An electronic device, characterized in that it comprises transmission means of audio signals according to any one of claims 1 to 7.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810587856.1A CN108810740B (en) | 2018-06-08 | 2018-06-08 | Audio signal transmission device and electronic equipment |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201810587856.1A CN108810740B (en) | 2018-06-08 | 2018-06-08 | Audio signal transmission device and electronic equipment |
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| Publication Number | Publication Date |
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| CN108810740A CN108810740A (en) | 2018-11-13 |
| CN108810740B true CN108810740B (en) | 2021-01-05 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN201810587856.1A Active CN108810740B (en) | 2018-06-08 | 2018-06-08 | Audio signal transmission device and electronic equipment |
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Families Citing this family (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110519525A (en) * | 2019-09-02 | 2019-11-29 | 深圳岚锋创视网络科技有限公司 | A kind of control system, method and the camera of the adaptive indicator light of camera |
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| CN201418142Y (en) * | 2009-05-22 | 2010-03-03 | 杨辉隆 | microphone |
| CN101998207A (en) * | 2009-08-27 | 2011-03-30 | 鸿富锦精密工业（深圳）有限公司 | Voice input device |
| CN102833650A (en) * | 2012-09-14 | 2012-12-19 | 南京莱斯信息技术股份有限公司 | AV (Audio/Video) control platform with microphone input module |
| CN203872342U (en) * | 2014-04-25 | 2014-10-08 | 比亚迪股份有限公司 | Sound acquiring device and vehicle with sound acquiring device |
| CN106787838A (en) * | 2017-02-28 | 2017-05-31 | 广东欧珀移动通信有限公司 | Power circuit and audio frequency apparatus |
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| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN2072301U (en) * | 1990-04-13 | 1991-02-27 | 张沪恩 | Electronic telephone transmitter |
| JP5340979B2 (en) * | 2010-02-09 | 2013-11-13 | 株式会社オーディオテクニカ | Stereo microphone |
| CN202550878U (en) * | 2012-02-27 | 2012-11-21 | 薛晓明 | DC voltage accurate isolator based on common optical coupler |
| CN104464787A (en) * | 2014-11-27 | 2015-03-25 | 天津天地伟业数码科技有限公司 | Circuit and method for controlling audio acquisition of embedded court trail all-in-one machine |
| CN105744452B (en) * | 2014-12-12 | 2019-04-02 | 瑞声声学科技(深圳)有限公司 | MEMS microphone circuit |
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2018
- 2018-06-08 CN CN201810587856.1A patent/CN108810740B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN201418142Y (en) * | 2009-05-22 | 2010-03-03 | 杨辉隆 | microphone |
| CN101998207A (en) * | 2009-08-27 | 2011-03-30 | 鸿富锦精密工业（深圳）有限公司 | Voice input device |
| CN102833650A (en) * | 2012-09-14 | 2012-12-19 | 南京莱斯信息技术股份有限公司 | AV (Audio/Video) control platform with microphone input module |
| CN203872342U (en) * | 2014-04-25 | 2014-10-08 | 比亚迪股份有限公司 | Sound acquiring device and vehicle with sound acquiring device |
| CN106787838A (en) * | 2017-02-28 | 2017-05-31 | 广东欧珀移动通信有限公司 | Power circuit and audio frequency apparatus |
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| CN108810740A (en) | 2018-11-13 |
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