CN205179338U - Headphone structure circuit of compatible multiple cell -phone system - Google Patents
Headphone structure circuit of compatible multiple cell -phone system Download PDFInfo
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- CN205179338U CN205179338U CN201520916336.2U CN201520916336U CN205179338U CN 205179338 U CN205179338 U CN 205179338U CN 201520916336 U CN201520916336 U CN 201520916336U CN 205179338 U CN205179338 U CN 205179338U
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- 230000001413 cellular effect Effects 0.000 claims 2
- 238000006243 chemical reaction Methods 0.000 description 10
- 230000005236 sound signal Effects 0.000 description 9
- 238000001514 detection method Methods 0.000 description 7
- 230000003247 decreasing effect Effects 0.000 description 5
- 230000002238 attenuated effect Effects 0.000 description 3
- 210000005069 ears Anatomy 0.000 description 3
- 230000000694 effects Effects 0.000 description 3
- XEEYBQQBJWHFJM-UHFFFAOYSA-N Iron Chemical compound [Fe] XEEYBQQBJWHFJM-UHFFFAOYSA-N 0.000 description 2
- 230000005540 biological transmission Effects 0.000 description 2
- 238000010586 diagram Methods 0.000 description 2
- 238000000034 method Methods 0.000 description 2
- 230000002093 peripheral effect Effects 0.000 description 2
- 230000009286 beneficial effect Effects 0.000 description 1
- 230000006870 function Effects 0.000 description 1
- 238000003780 insertion Methods 0.000 description 1
- 230000037431 insertion Effects 0.000 description 1
- 229910052742 iron Inorganic materials 0.000 description 1
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- 230000026683 transduction Effects 0.000 description 1
- 238000010361 transduction Methods 0.000 description 1
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Abstract
The utility model discloses a headphone structure circuit of compatible multiple cell -phone system, reduce switch K2, volume increase switch K3 including microprocessor U1, plug, microphone MIC, earphone left side earphone L -earphone, earphone right side earphone R -earphone and broadcast switch K1, volume, microprocessor U1 is last to be set up microphone offset voltage pin MICBIAS, left passageway input pin lin, right passageway input pin lin, left passageway output pin lout, right passageway output pin lout, volume and reduces pin DOWN, volume increase pin UP and ground pin GND. The utility model discloses can compatible ann zhuo, various present cell -phone systems such as iso system, be applicable to the earphone field that the volume need be adjusted to the volume control of drive -by -wire earphone and other, simple structure, with low costs and convenient to use, reduce switch K2 and volume increase switch K3 through broadcast switch K1, volume, and switch microphone and audio playback, convenient and fast through transistor Q1.
Description
Technical Field
The utility model relates to an earphone volume control technique especially relates to a compatible multiple cell-phone system's earphone control circuit.
Background
From the development of the whole audio industry, the wireless headset still is a new thing, the development time is not long, the user demand is continuously increased in the rising period at present, the expected value of the user on the wireless headset is also increased, and the new test is provided for the industry. At present, the most concerned key points of users comprise tone quality, cruising ability and wireless transmission ability, from the data point of view, the wireless transmission ability can basically meet the requirements of most users, and the tone quality and cruising ability have great promotion potential, and if the promotion is started from the two points, the user eyes can be easily attracted in the future.
The earphone is a pair of conversion units which receive the electric signals sent by the media player or receiver and convert the electric signals into audible sound waves by using a loudspeaker close to the ear. The headset is typically detachable from the media player and utilizes a plug connection. The advantage is that the user can listen to the sound independently without influencing other people; can also isolate the sound of the surrounding environment, and is very helpful for people who use in noisy environment such as recording rooms, DJ, trips, sports, and the like. The earphone is originally used for the telephone and the radio, but with the prevalence of portable electronic devices, the earphone is mostly used for mobile phones, walkmans and radios. Portable electronic games and digital audio players. From the development of the whole audio industry, the wireless headset still is a new thing, the development time is not long, at present, the user demand is continuously improved, the expected value of the wireless headset of the user is also improved, and the new examination is provided for the industry.
The earphone is a symbol of a person's carry-on sound. The mobile phone earphone is divided into two standards: the OMTP standard is commonly called the national standard and CTIA is called the international standard. Earphones are classified according to their transduction mode, mainly including: a moving coil system, a moving iron system, an electrostatic system, and an equivalent magnetic system. The functional mode is classified structurally, and the device can be divided into a semi-open type and a closed type; ear plugs, ear hooks, ear insertion and head are classified from wearing forms; single earphones and multi-person earphones are classified according to the number of people wearing the earphones; the earphone is distinguished from a sound source and can be divided into an active earphone and a passive earphone; active headsets are also often referred to as paddle-card headsets.
The method for evaluating the sound box can be used for measuring the earphone, but the hearing sense of the earphone is different from that of the sound box, sound waves emitted by the sound box are attenuated and interfered in the air and interact with the head and the ears of a person, and the sound of the earphone directly enters the ears. The sound quality of the earphone is more important than the technical performance of the earphone, because the shapes of the head and the ears of a person are different, and a pair of earphones has different audiences for different people, the earphone is recommended to be only used as a reference, and the earphone sound can be really felt only by listening in person.
However, in the prior art, the compatibility of the earphones of each brand of mobile phone is poor, and when another mobile phone is accessed, the tone quality is poor and the user experience is poor.
SUMMERY OF THE UTILITY MODEL
An object of the utility model is to overcome prior art's is not enough, provides a compatible multiple cell-phone system's earphone control circuit, various current cell-phone systems such as compatible ann tall and erect, iso system, and application scope is wide, and simple structure, and is with low costs.
In order to achieve the above purpose, the utility model discloses a technical scheme is:
an earphone control circuit compatible with various mobile phone systems,
the earphone comprises a microprocessor U1, a plug, a microphone MIC, an earphone left receiver L-earphone, an earphone right receiver R-earphone, a play switch K1, a volume reduction switch K2 and a volume increase switch K3;
a microphone bias voltage pin MICBIAS, a left channel input pin Lin, a right channel input pin Lin, a left channel output pin Lout, a right channel output pin Lout, a volume reduction pin DOWN, a volume increase pin UP and a ground pin GND are arranged on the microprocessor U1;
the microphone bias voltage pin MICBIAS is respectively connected with a microphone MIC and a play switch K1; the left channel input pin Lin and the right channel input pin Lin are connected with a plug; the volume reduction pin DOWN is connected with a volume reduction switch K2; the volume increasing pin UP is connected with a volume increasing switch K3; the left channel output pin Lout is connected with an earphone left receiver L-earphone; the right channel output pin Lout is connected with an earphone right receiver R-ear phone; the ground pin GND is connected with a ground terminal.
As the best embodiment of the present invention, the output terminal of the MIC bias voltage pin is provided with a transistor Q1, the gate of the transistor Q1 is connected to the MIC bias voltage pin, the source of the transistor Q1 is connected to the ground all the way, the other way is connected to the play switch K1, the drain of the transistor Q1 is connected to the one end of the microphone MIC, and the drain of the transistor Q1 is connected to a resistor R3 in series to connect the other end of the microphone MIC.
As a preferred embodiment of the present invention, the transistor Q1 is an NMOS transistor.
As the best embodiment of the present invention, a diode D1 is provided between the microphone MIC and the microphone bias voltage pin MICBIAS, the microphone MIC is connected to the anode of the diode D1, and the microphone bias voltage pin MICBIAS is connected to the cathode of the diode D1.
As a preferred embodiment of the present invention, the mic bias voltage pin of the present invention is connected in series with a capacitor C1 for grounding.
As the best embodiment of the utility model, the plug of the utility model is provided with a left channel input pin Lin interface, a right channel input pin Lin interface, a microphone MIC interface and a GND interface; the left channel input pin Lin interface is connected with the left channel input pin Lin, the right channel input pin Lin interface is connected with the right channel input pin Lin, the microphone MIC interface is connected with the microphone MIC, and the GND interface is grounded.
As the best embodiment of the utility model, ground connection behind the left side passageway input pin Lin interface series connection resistance R1, ground connection behind the right side passageway input pin Lin interface series connection resistance R2.
As a preferred embodiment of the present invention, the microprocessor U1 of the present invention includes a key detection module, a counting control module, a level conversion module, an attenuation output module and a charge pump module; wherein,
the key detection module is used for detecting a volume-up signal or a volume-down signal input by a key and then outputting a control signal;
the counting control module is used for receiving the control signal and outputting a counting value signal, carrying out addition counting if the control signal is a volume increasing control signal sent by pressing a volume increasing switch K3, and carrying out subtraction counting if the control signal is a volume decreasing control signal sent by pressing a volume decreasing switch K2;
the level conversion module is used for converting the level of the count value signal and outputting the converted count value signal;
the attenuation output module is used for attenuating the received converted count value signal, the input left channel audio signal and the input right channel audio signal and then outputting the audio signals through a left channel output pin Lout and a right channel output pin Lout;
the charge pump module is used for generating a negative power supply and outputting the negative power supply to the level conversion module and the attenuation output module, so that the level conversion module and the attenuation output module work between the negative power supply and the positive power supply.
As a preferred embodiment of the present invention, the attenuation output module of the present invention includes 1 st to n resistors, 1 st to n switches, n +1 st to 2n resistors, and n +1 st to 2n switches; one ends of the 1 st to n-th resistors are connected with the right channel input pin Lin, the other ends of the 1 st to n-th resistors are respectively connected with one ends of the 1 st to n-th switches one by one, and the other ends of the 1 st to n-th switches are connected with the right channel output pin Lout; one end of each of the n +1 th to 2n th resistors is connected with the left channel input pin Lin, the other end of each of the n +1 th to 2n th resistors is connected with one end of each of the n +1 th to 2n th switches one by one, the other end of each of the n +1 th to 2n th switches is connected with the left channel output pin Lout, and n is an integer greater than 1.
As a preferred embodiment of the present invention, the charge pump module provides a negative power supply for the circuit.
Compared with the prior art, the beneficial effects of the utility model are that: the first compatible with various existing mobile phone systems such as android and iso systems is suitable for the volume control of line control earphones and other earphone fields needing volume adjustment, and has the advantages of simple structure, low cost and convenient use; secondly, through broadcast switch K1, volume reduction switch K2 and volume increase switch K3, and switch over microphone and audio playback through transistor Q1, convenient and fast.
Drawings
Fig. 1 is a schematic view of the overall structure of the present invention;
fig. 2 is a schematic diagram of the internal structure of the microprocessor according to the present invention.
Detailed Description
The utility model discloses an it is not enough to overcome prior art, provides a compatible multiple cell-phone system's headphone control circuit, can adapt to different cell-phones, for example various current cell-phone systems such as compatible ann is tall and erect, iso system can receive better tone quality effect. The following detailed description is provided to further explain the technical features and advantages of the present invention by referring to the accompanying drawings in combination with the embodiments.
The utility model discloses an overall structure schematic diagram is shown in FIG. 1, a compatible multiple cell-phone system's earphone control circuit, including microprocessor U1, plug, microphone MIC, earphone left side earphone L-earphone, earphone right side earphone R-earphone and play switch K1, volume reduction switch K2, volume increase switch K3.
Preferably, the microprocessor U1 of the present invention employs a chip ST 2618. ST2618 is a volume control circuit (maximum attenuation is MUTE) for general earphone controlled by keys, and it includes a key detection module, a count control module, an attenuation output module, a level conversion module, and a charge pump module. The key input is detected through the key detection module, the count value of the count control module is adjusted to control the attenuation output module to select different attenuation resistance values, so that the external audio signal input to the attenuation output module is output to the earphone after being attenuated by the attenuation resistance, and the volume of the earphone is controlled. The high-resistance output is realized through the attenuation output module, the mute function is realized, and the mute effect can be obtained on the earphone; and a fifth built-in charge pump module greatly reduces peripheral devices while realizing that the output audio signal is 0V in analog ground.
The circuit detects the input of the UP and the DOWN of the keys through the key detection module, controls the internal counter to add or subtract, and then controls the attenuation output module to select different attenuation resistors through the count value, so that the audio signal is attenuated and output to the earphone. ST2618 is applicable to drive-by-wire earphone volume and other earphone fields that need to adjust the volume. A built-in charge pump circuit is used to provide the negative voltage. UP: UP is used to increase the output volume and the output resistance is selectively decreased by the switch. DOWN: DOWN is used to reduce the output volume and the output resistance is selectively increased by a switch. pull-UP resistors are arranged in the UP and DOWN pins, and the circuit can change the switch to adjust the output resistance only when the key is pressed DOWN for more than 40ms of anti-shake time. When the key is pulled down continuously, the switch is adjusted every 200ms to change the output resistance. ST2618 maximum operating current is less than 10 uA.
As shown in fig. 2, the microprocessor U1 has a microphone bias voltage pin MICBIAS, a left channel input pin Lin, a right channel input pin Lin, a left channel output pin Lout, a right channel output pin Lout, a volume DOWN pin DOWN, a volume UP pin UP, and a ground pin GND. The microphone bias voltage pin MICBIAS is respectively connected with a microphone MIC and a play switch K1; the left channel input pin Lin and the right channel input pin Lin are connected with a plug; the volume reduction pin DOWN is connected with a volume reduction switch K2; the volume increasing pin UP is connected with a volume increasing switch K3; the left channel output pin Lout is connected with an earphone left receiver L-earphone; the right channel output pin Lout is connected with an earphone right receiver R-ear phone; the ground pin GND is connected with a ground terminal.
Preferably, microphone bias voltage pin MICBIAS's output sets up a transistor Q1, and microphone bias voltage pin MICBIAS is connected to transistor Q1's grid, and transistor Q1's source is ground all the way, and another way is connected and is played switch K1, and the one end of microphone MIC is connected to transistor Q1's drain electrode, and transistor Q1's drain electrode series resistance R3 connects the other end of microphone MIC.
In order to reach better switch switching effect, transistor Q1 is the NMOS transistor, VT = 1V. Of course, the present invention is not limited to the NMOS transistor, and may be other transistors.
The utility model discloses a prevent reverse voltage electric current set up a diode D1 between microphone MIC and the microphone bias voltage pin MICBIAS, the microphone MIC is connected to diode D1's positive pole, and the microphone bias voltage pin MICBIAS is connected to diode D1's negative pole. A diode D1 is arranged between the microphone MIC and the microphone bias voltage pin MICBIAS to form a reverse cut-off circuit, so that the circuit damage caused by reverse current is prevented, and the safety performance is improved.
As the best embodiment of the present invention, the microphone bias voltage pin MICBIAS is connected with a capacitor C1 in series and then grounded, and is isolated from the ground end to form a protection.
The plug of the utility model is provided with a left channel input pin Lin interface, a right channel input pin Lin interface, a microphone MIC interface and a GND interface; the left channel input pin Lin interface is connected with the left channel input pin Lin, the right channel input pin Lin interface is connected with the right channel input pin Lin, the microphone MIC interface is connected with the microphone MIC, and the GND interface is grounded. Additionally, left side passageway input pin Lin interface another way ground connection behind the series connection resistance R1, right side passageway input pin Lin interface another way ground connection behind the series connection resistance R2.
The microprocessor U1 of the utility model comprises a key detection module, a counting control module, a level conversion module, an attenuation output module and a charge pump module; the key detection module is used for detecting a volume-up signal or a volume-down signal input by a key and then outputting a control signal; the counting control module is used for receiving the control signal and outputting a counting value signal, carrying out addition counting if the control signal is a volume increasing control signal sent by pressing a volume increasing switch K3, and carrying out subtraction counting if the control signal is a volume decreasing control signal sent by pressing a volume decreasing switch K2; the level conversion module is used for converting the level of the count value signal and outputting the converted count value signal; the attenuation output module is used for attenuating the received converted count value signal, the input left channel audio signal and the input right channel audio signal and then outputting the audio signals through a left channel output pin Lout and a right channel output pin Lout; the charge pump module is used for generating a negative power supply and outputting the negative power supply to the level conversion module and the attenuation output module, so that the level conversion module and the attenuation output module work between the negative power supply and the positive power supply. The charge pump module provides the negative supply for the circuit, need not extra peripheral device simultaneously.
As a preferred embodiment of the present invention, the attenuation output module of the present invention includes 1 st to n resistors, 1 st to n switches, n +1 st to 2n resistors, and n +1 st to 2n switches; one ends of the 1 st to n-th resistors are connected with the right channel input pin Lin, the other ends of the 1 st to n-th resistors are respectively connected with one ends of the 1 st to n-th switches one by one, and the other ends of the 1 st to n-th switches are connected with the right channel output pin Lout; one end of each of the n +1 th to 2n th resistors is connected with the left channel input pin Lin, the other end of each of the n +1 th to 2n th resistors is connected with one end of each of the n +1 th to 2n th switches one by one, the other end of each of the n +1 th to 2n th switches is connected with the left channel output pin Lout, and n is an integer greater than 1. Preferably, the value of n is set according to the number of stages of volume adjustment required by the headset, n is an integer from 2 to 99, as shown in fig. 2, and n is 11.
In a specific embodiment, the attenuation output module includes 1 st to n th resistors R1, R2, R3 … … Rn, 1 st to n th switches K1, K2, K3 … … Kn, n +1 st to 2n th resistors R (n + 1), R (n +2) … … R (2 n), and n +1 st to 2n th switches K (n + 1), K (n +2) … … K (2 n); one ends of the 1 st to n-th resistors R1, R2 and R3 … … Rn are connected with a right channel input pin Lin, the other ends of the 1 st to n-th resistors R1, R2 and R3 … … Rn are respectively connected with one ends of the 1 st to n-th switches K1, K2 and K3 … … Kn one by one, and the other ends of the 1 st to n-th switches K1, K2 and K3 … … Kn are connected with a right channel output pin Lout; one ends of the n +1 th to 2 n-th resistors R (n + 1) and R (n +2) … … R (2 n) are connected with the left channel input pin Lin, the other ends of the n +1 th to 2 n-th resistors R (n + 1) and R (n +2) … … R (2 n) are respectively connected with one ends of the n +1 th to 2 n-th switches K (n + 1) and K (n +2) … … K (2 n) one by one, and the other ends of the n +1 th to 2 n-th switches K (n + 1) and K (n +2) … … K (2 n) are connected with the left channel output pin Lout.
The present invention is described in detail in the above embodiments, and it should be understood that the described embodiments are not limited to the embodiments of the present invention. Based on the embodiments in the present invention, all other embodiments obtained by a person skilled in the art without creative work belong to the protection scope of the present invention.
Claims (7)
1. The utility model provides a compatible multiple cell-phone system's earphone control circuit which characterized in that:
the earphone comprises a microprocessor U1, a plug, a microphone MIC, an earphone left receiver L-earphone, an earphone right receiver R-earphone, a play switch K1, a volume reduction switch K2 and a volume increase switch K3;
a microphone bias voltage pin MICBIAS, a left channel input pin Lin, a right channel input pin Lin, a left channel output pin Lout, a right channel output pin Lout, a volume reduction pin DOWN, a volume increase pin UP and a ground pin GND are arranged on the microprocessor U1;
the microphone bias voltage pin MICBIAS is respectively connected with a microphone MIC and a play switch K1; the left channel input pin Lin and the right channel input pin Lin are connected with a plug; the volume reduction pin DOWN is connected with a volume reduction switch K2; the volume increasing pin UP is connected with a volume increasing switch K3; the left channel output pin Lout is connected with an earphone left receiver L-earphone; the right channel output pin Lout is connected with an earphone right receiver R-ear phone; the ground pin GND is connected with a ground terminal.
2. The headset control circuit compatible with multiple cellular phone systems of claim 1, wherein: the output end of the microphone bias voltage pin MICBIAS is provided with a transistor Q1, the grid electrode of the transistor Q1 is connected with the microphone bias voltage pin MICBIAS, one path of the source electrode of the transistor Q1 is grounded, the other path of the source electrode of the transistor Q1 is connected with the play switch K1, the drain electrode of the transistor Q1 is connected with one end of the microphone MIC, and the drain electrode of the transistor Q1 is connected with a resistor R3 in series and is connected with the other end of the microphone MIC.
3. The headset control circuit of claim 2, further comprising: the transistor Q1 is an NMOS transistor.
4. The headset control circuit of claim 2, further comprising: a diode D1 is arranged between the microphone MIC and the microphone bias voltage pin MICBIAS, the anode of the diode D1 is connected with the microphone MIC, and the cathode of the diode D1 is connected with the microphone bias voltage pin MICBIAS.
5. The headset control circuit of claim 2, further comprising: the mic bias voltage pin MICBIAS is connected in series with a capacitor C1 and then to ground.
6. The headset control circuit compatible with multiple cellular phone systems of claim 1, wherein: the plug is provided with a left channel input pin Lin interface, a right channel input pin Lin interface, a microphone MIC interface and a GND interface; the left channel input pin Lin interface is connected with the left channel input pin Lin, the right channel input pin Lin interface is connected with the right channel input pin Lin, the microphone MIC interface is connected with the microphone MIC, and the GND interface is grounded.
7. The headset control circuit of claim 6, further comprising: the interface of the left channel input pin Lin is connected with a resistor R1 in series and then grounded, and the interface of the right channel input pin Lin is connected with a resistor R2 in series and then grounded.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520916336.2U CN205179338U (en) | 2015-11-17 | 2015-11-17 | Headphone structure circuit of compatible multiple cell -phone system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201520916336.2U CN205179338U (en) | 2015-11-17 | 2015-11-17 | Headphone structure circuit of compatible multiple cell -phone system |
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| CN205179338U true CN205179338U (en) | 2016-04-20 |
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| CN201520916336.2U Expired - Fee Related CN205179338U (en) | 2015-11-17 | 2015-11-17 | Headphone structure circuit of compatible multiple cell -phone system |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108495222A (en) * | 2018-03-14 | 2018-09-04 | 佳禾智能科技股份有限公司 | Double compatible line control earphone control circuits and the control method realized based on the circuit |
-
2015
- 2015-11-17 CN CN201520916336.2U patent/CN205179338U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN108495222A (en) * | 2018-03-14 | 2018-09-04 | 佳禾智能科技股份有限公司 | Double compatible line control earphone control circuits and the control method realized based on the circuit |
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| 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: 20160420 Termination date: 20161117 |
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| CF01 | Termination of patent right due to non-payment of annual fee |