CN204272368U - A kind of earphone with active digital three frequency division system - Google Patents
A kind of earphone with active digital three frequency division system Download PDFInfo
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- CN204272368U CN204272368U CN201420456173.XU CN201420456173U CN204272368U CN 204272368 U CN204272368 U CN 204272368U CN 201420456173 U CN201420456173 U CN 201420456173U CN 204272368 U CN204272368 U CN 204272368U
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- earphone
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- frequency division
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Abstract
The utility model discloses a kind of earphone with active digital three frequency division system, comprise a housing, described housing is provided with audio signal input end mouth and Audio output port, the earphone pronunciation portion be connected with Audio output port; Active digital three frequency division system is provided with in described housing, described active digital three frequency division system comprises: main control module, digital signal input selection module, digital signal processing module, six road amplifier modules and provide the power module of power supply for above-mentioned all modules, described digital signal processing module is connected with described digital signal input selection module and six road amplifier modules, described digital signal input selection module is connected with audio signal input end mouth, and described six road amplifier modules are connected with Audio output port.It has part-frequency point arrange simple clear and definite, rapid decay slope, the low advantage of phase shift, distortion can not be produced, make whole earphone can at utmost also original sound really.
Description
Technical field
The utility model relates to a kind of earphone, particularly relates to a kind ofly to have the multiple part-frequency point of sound unit, the earphone of multichannel pmultiple amplifier.
Background technology
Music is ubiquitous, today that technology is maked rapid progress, and requires that more and more higher crowd is more and more huger to music quality, along with the application of smart mobile phone on music player and high definition can't harm the rise of music player and the popular of high definition music file.The requirement of advanced level user to music playback is also more and more higher, original technology has been difficult to the requirement reaching them, and the high definition as signal source can't harm player and propagates its belief on a large scale, prior playback section earphone, but also rest on technology several years ago, defect also more and more embodies.Its one of the main reasons is the sound wave that a pronunciation unit will send whole sound audio 20Hz-20KHz simultaneously.When the music signal senior middle school low frequency comprised in music signal enriches all very much; the single vibrating diaphragm of pronunciation unit will send the sound of senior middle school's low frequency; burden can be very large; low-and high-frequency can not be taken into account; the sound sent will thicken; produce serious distortion simultaneously, locate inaccurate drawback, so this earphone is difficult to meet high-end user group, sound is perfectly pursued.
Existing simulation frequency division earphone simultaneously, with inductance L, electric capacity C and resistance R as frequency divider, this method part-frequency point is difficult to realize, and high pitch is overlapping with middle pitch, and middle pitch is overlapping with bass, use LCR can reduce the sensitivity of earphone and increase phase deviation, make each pronunciation element sensitivity distribution type difficult, cause audio distortions serious, fuzzy, simultaneously LCR is contained in same cavity and can gains in weight, and wearing comfort reduces.The attenuation slope of LCR frequency divider only has-3dB, and the frequency response of pronunciation unit is all also many than +/-3dB, causes part-frequency point can not be clear and definite, it is many that frequency division excessively puts overlapping part, the outstanding problem of linking, and multiple unit sends same music signal simultaneously, cause sound fuzzy, obscure boundary is clear.Can produce after pronunciation unit serial connection LCR phase shift, boundary's number more much more serious, sound thickens, it is inaccurate to locate, clever lightness also can reduce.
Utility model content
Whole frequency band sound to be sent for one of earphone in prior art pronunciation unit, high-low sound frequency part-frequency point fuzzy, phase deviation when can not take into account and simulate LC frequency division, valence mumber more much more serious, obscure boundary, overlapping sounding thus cause the drawback that playback sound is fuzzy, distortion is serious, the earphone with active digital three frequency division system that the purpose of this utility model is to provide a kind of clear sound, accurate positioning, distortion little.
To achieve these goals, the technical scheme that the utility model adopts is: a kind of earphone with active digital three frequency division system, comprise a housing, described housing is provided with audio signal input end mouth and Audio output port, the earphone pronunciation portion be connected with Audio output port; Active digital three frequency division system is provided with in described housing, described active digital three frequency division system comprises: main control module, digital signal input selection module, digital signal processing module, six road amplifier modules and provide the power module of power supply for above-mentioned all modules, described digital signal processing module is connected with described digital signal input selection module and six road amplifier modules, described digital signal input selection module is connected with audio signal input end mouth, and described six road amplifier modules are connected with Audio output port.
Described main control module connects described digital signal input selection module and described digital signal processing module.
The described audio signal input end mouth be connected with digital signal input selection module is that coaxial digital signal input end mouth is or/and optical fiber and digital signal input port.
Described digital signal processing module is also connected with stereo analog input port.
Described Audio output port is 8 pin earphone output sockets.
Described earphone pronunciation portion comprises 8 pin plugs, 8 core earphone cords, earphone left and right deconcentrator and the left and right pronunciation unit earphone cavity that are connected successively.
Also comprise chargeable chip in described power module, described housing also comprises USB interface, described USB interface is connected with chargeable chip.
Its operation principle is: power module is main control module, input signal selects module, digital signal processing module and six road amplification modules to power; Left-right stereo two sound channel music signal enters digital signal input selection module, and user selects input signal by main control module; At the part-frequency point that the process of digital signal processing module internal digital is preset, stereo two sound channel signal process are divided into left and right acoustic channels high pitch, left and right acoustic channels middle pitch, left and right acoustic channels bass three part, totally six tunnels, user controls volume by volume potentiometer adjustment output level again, adjustment Hou six road signal enters No. six device amplification modules respectively and is amplified to and is enough to promote pronunciation unit and sounds, more respectively the high pitch after amplification, middle pitch, bass part is delivered to the unit that pronounces accordingly through eight core output ports, eight core connecting lines; Pronunciation unit is sounded and is supplied user to listen to.
Compared with prior art, described in the utility model have active digital three frequency division system that active digital three frequency division system adopts and have part-frequency point than common LC frequency division and arrange simple clear and definite, the slope of rapid decay, digital frequency division and can not produce the low advantage of phase shift, distortion, and earphone inside cavity does not need to install LCR, make earphone relatively slim and graceful, wear comfortable; The utility model adopts No. six amplifiers by connecting line to pronunciation unit simultaneously, every road amplifier can according to the adjustment of sensitivity multiplication factor of each unit that pronounces, each pronunciation unit only need send the music signal in default frequency range and become free and relaxed, clear sound, accurate positioning, distortion be little, make whole earphone at utmost can go back original sound really, more can meet music-lover and the audiophile crowd of high request.
In order to further understand feature of the present utility model and technology contents, refer to following about detailed description of the present utility model and accompanying drawing, but accompanying drawing only provide reference and explanation use, is not used for being limited the utility model.
Accompanying drawing explanation
Below in conjunction with accompanying drawing, by describing in detail embodiment of the present utility model, will make the technical solution of the utility model and other beneficial effect apparent.
In accompanying drawing,
Fig. 1 is a kind of circuit structure block diagram with the earphone of active digital three frequency division system described in the utility model;
Fig. 2 is a kind of stereogram with the earphone of active digital three frequency division system described in the utility model;
Fig. 3 is a kind of vertical view with the earphone of active digital three frequency division system described in the utility model;
Fig. 4 is a kind of integrated circuit structure chart with the active digital three frequency division system of the earphone of active digital three frequency division system described in the utility model;
Fig. 5 is a kind of circuit structure diagram with the main control module of the active digital three frequency division system of the earphone of active digital three frequency division system described in the utility model;
Fig. 6 is a kind of circuit structure diagram with the power module of the active digital three frequency division system of the earphone of active digital three frequency division system described in the utility model;
Fig. 7 is the circuit structure diagram of the power subsystem that a kind of power module Zhong Wei six road amplifier module with the active digital three frequency division system of the earphone of active digital three frequency division system described in the utility model is powered;
Fig. 8 is a kind of circuit structure diagram with the active digital three frequency division system Wei six road amplifier module plant-grid connection unit of the earphone of active digital three frequency division system described in the utility model;
Fig. 9 is a kind of circuit structure diagram with the digital signal input selection module of the active digital three frequency division system of the earphone of active digital three frequency division system described in the utility model;
Figure 10 is a kind of circuit structure diagram with the digital signal processing module of the active digital three frequency division system of the earphone of active digital three frequency division system described in the utility model;
Figure 11 is a kind of circuit structure diagram with six road amplifier modules of the active digital three frequency division system of the earphone of active digital three frequency division system described in the utility model;
Figure 12 is a kind of circuit structure diagram with 8 core sockets of the earphone of active digital three frequency division system described in the utility model.
In figure:
100, main control module; 101, digital signal input selection module; 102, digital signal processing module; 103, six road amplifier modules; 104, power module; 105,8 core earphone connecting lines; 106, multiple sound unit earphone cavity;
1,8 pin earphone accessory power outlets; 2, power supply indicator; 3, the volume potentiometer of belt switch; 4, stereo analog two sound channel input; 5, coaxial digital signal input end; 6, optical fiber and digital signal input part; 7, usb connecting port; 8, housing; 9,8 core headset plugs; 10, earphone cord left and right deconcentrator.
Embodiment
For further setting forth the technological means and effect thereof that the utility model takes, be described in detail below in conjunction with preferred embodiment of the present utility model and accompanying drawing thereof.
With specific embodiments and the drawings is described further by the utility model.
Consult Fig. 1, Fig. 2 and Fig. 3, present embodiments provide a kind of earphone with active digital three frequency division system, comprise a housing 8, described housing 8 is provided with coaxial digital signal input end 5, optical fiber and digital signal input part 6 and 8 core headset plug 9, the earphone pronunciation portion be connected with 8 core headset plugs 9; Active digital three frequency division system is provided with in described housing 8, described active digital three frequency division system comprises: main control module 100, digital signal input selection module 101, digital signal processing module 102, six road amplifier modules 103 and provide the power module 104 of power supply for above-mentioned all modules; Input, the output of described digital signal processing module 102 are connected with the output of described digital signal input selection module 101 and the input of six road amplifier modules 103 respectively, the input of described digital signal input selection module 101 is connected with coaxial digital signal input end 5, optical fiber and digital signal input part 6, and the output of described six road amplifier modules 103 is connected with multiple sound unit earphone cavity 106 by 8 core headset plug 9 and 8 core earphone connecting lines 105; Described earphone pronunciation portion comprises 8 pin plug 9, the 8 core earphone cords 105, earphone left and right deconcentrator 10 and the multiple sound unit ear cavity 106 that are connected successively.
Consult Fig. 4 and Fig. 5, main control module 100 described in the present embodiment by model be C8051F340 Master control chip U5, external model is the storage chip FLASH holder U4 of SST25VF032B, control switch and Led display lamp, filter capacitor and pull-up resistor are formed; Wherein the 2nd pin of FLASH holder U4 is connected with the 48th pin of Master control chip U5 through R9, and the 5th pin is connected with Master control chip U5 the 46th pin through R7, and the 6th pin is connected with Master control chip U5 the 48th pin through R9; It is the instruction of stereo analog input state that 39th pin of Master control chip U5 connects Led D1, and during the input of Systematic selection stereo analog, this pin is low level, and Led lights, otherwise is high level, and Led goes out; It is the instruction of optical fiber input state that Master control chip U5 the 42nd pin connects Led D3, and during the input of Systematic selection optical fiber, this pin is low level, and Led lights, otherwise is high level; It is the instruction of coaxial input state that Master control chip U5 the 43rd pin connects Led D4, and when Systematic selection coaxially inputs, this pin is low level, and Led lights, otherwise is high level, and Led goes out; Master control chip U5 the 33rd pin connects SW1, R32, R35, R37 through R22 and forms bleeder circuit, SW1 position volume control potentiometer, controlled by bleeder circuit, user carries out volume adjusting by volume potentiometer SW1, to be applicable to the volume requirement of oneself, U5 receives the instruction of SW1 volume adjusting, carries out digital volume control by serial ports to U6.
Consult Fig. 4, Fig. 7 and Fig. 8, after in described power module 104, mains switch W1 opens, pass through circuit, it is that the voltage transformation being input to its 8th pin becomes negative voltage to export from the 5th pin by LM2662M switching capacity electric pressure converter U10 that power supply enters into model, to give respectively through inductance L 3, inductance L 7 be OPA1612 by three models be amplification chip U1, amplification chip U2, amplification chip U3 form six road Earphone Amplifiers, 8 pin that voltage is input to and 4 pin provide the power supply of generating positive and negative voltage for them, guarantee that they normally work; Consult Fig. 4, Fig. 6 and Figure 10, power supply model in DV1 supply power module 104 is power supply input the 4th pin of the 1.8V voltage stabilizing chip U11 of LT3406, its the 5th pin is output voltage adjustment pin, realize 1.8V voltage stabilizing by outside R94, R95,1.8V voltage stabilizing chip U11 export 1.8V voltage through L4, C79 filtering by L5, L6 be connected respectively to the digital signal processing chip U6 that model is CS47048 digital circuit 1.8V input pin the 11st, 22,35 pin and analog circuit 1.8V input pin the 75th pin provide operating voltage; Power supply model in DV2 supply power module 104 is voltage input the 7th pin of the voltage stabilizing chip U13 of the 3.3V of LT3440, voltage stabilizing circuit is formed by L8, R103, R98, R100,6th pin export the stable voltage of 3.3V be connected to after L9, L10, C102, C103 filtering digital circuit the 5th that model is the digital signal processing chip U6 of CS47048,16,30 pin, with analog circuit the 62nd, 64,79,85,91 and 97 pin, the operating voltage of supply 3.3V, they provide sufficient, clean operating current operating voltage for system.
Consult Fig. 4, Fig. 5, Fig. 9 and Figure 10, after the power supply connection of complete machine, machine enters operating state, the input port of described digital signal processing module 102 is connected with coaxial digital signal input end mouth JK1 and optical fiber and digital signal input port P3, as signal is input to coaxial digital signal input end mouth JK1, enter through coupling capacitor C30 the 3rd pin that model is the inverter U8 of NC7WZ04, be connected with the 2nd pin that model is the signal input selection chip U7 of ADG704 from the 6th pin output; As signal is input to optical fiber and digital signal input port P3, be connected with the 9th pin of signal input selection chip U7 through coupling capacitor C40, the 1st pin is connected with the 2nd pin of Master control chip U5 through R64, and the 10th pin is connected with the 3rd pin of Master control chip U5 through R75.By being connected to the S1 selector switch of Master control chip U5 the 31st pin, S1 is the P2.7 function port of Master control chip U5, the switch receiving terminal be defined as, by this port accepts to selection instruction, signal input selection chip U7 chooses wherein one group of signal and exports from the 8th pin, be connected with the 10th pin of digital signal processing chip U6 by R52, enter into digital signal processing chip U6 and carry out complicated Digital Signal Processing.
Consult Fig. 6, also comprising model MCP73863 in described power module 104 is battery charging chip U12, be connected with the 2nd, the 3rd pin of battery charging chip U12 by the VBUS supply pin of USB P4, charge the battery chip U12 supply voltage, C86 filter capacitor connects battery charging chip U12 the 2nd, the 3rd pin, the 15th pin connects Led D8 the 3rd pin, is charging indicator light, and during charged state, Led is red, 16th pin is that battery is full of indicator light, is green light when being full of.Battery charging chip U12 the 10th, 11,12 pin is connected with battery positive, and C80 connects battery two ends, and R93, R101, R102, R104, C99 are auxiliary circuit, ensures that circuit normally works; Diode D9 positive pole connects anode, and negative terminal is linked on mains switch W1 one end, and diode D7 is connected to one end of USB power source end and mains switch, and mains switch is opened greatly rear to system power supply.
Consult Fig. 4, Fig. 5 and Figure 10, stereo analog signals is linked into stereo analog input port P2, through R61, R70, R65, R69 dividing potential drop, by electric capacity C32, C33 is connected to the analog input the 66th that model is CS47048 digital signal processing chip U6, 68 pin enter into digital signal processing chip U6 and carry out complicated digital processing, the 36th of digital signal processing chip U6, 37 pin and external crystal oscillator X1, C15, C19, R33 forms clock circuit, reference clock is provided to system, 24th pin of digital signal processing chip U6 is connected with the 46th pin of Master control chip U5 through resistance R10, 26th pin of digital signal processing chip U6 is connected with the 1st pin of Master control chip U5 through resistance R23, the 25th of digital signal processing chip U6, 27, 28, 29 pin are respectively with the 48th of Master control chip U5, 29, 6, 5 are connected, the control connection of composition serial ports, the pin that control signal is connected by these transmits, realize the control to digital signal processing chip U6.
Consult Fig. 4, Figure 10, Figure 11 and Figure 12, digital signal processing chip U6 in described digital signal processing module 102, the signal digital of access is processed into the part-frequency point preset and carries out frequency division, by the signal of stereo left and right two sound channel, frequency division is left high pitch, left sound, left bass and right high pitch, right sound, right bass three Zu Gong six road signal, its concrete operation principle is as follows: digital signal processing chip U6 the 99th pin exports left high pitch and closes through electric capacity C1 lotus root, R11 is connected to 3 pin of amplifier U1, by R117, R13, R15, R16, C5, C6 forms 1 times of amplifier and amplifies, meet R13 from the output of amplifier U1 first pin again and be connected to 8 pin accessory power outlet J5 the 5th pin, be connected to the inner corresponding voice unit of earphone by 8 pin plugs and connecting line to sound, digital signal processing chip U6 the 93rd pin exports left sound and closes through electric capacity C18 lotus root, R34 is connected to amplifier U2 the 3rd pin, form 1 times of amplifier by R119, R36, R40, R41, C21 and C22 to amplify, export from amplifier U2 the 1st pin again and meet R36 and be connected to 8 pins and belong to socket J5 the 4th pin, be connected to the inner corresponding alto units of earphone by 8 pin plugs and connecting line and sound, the left bass that digital signal processing chip U6 the 87th pin exports closes through C31 lotus root, and R61 is connected to U3 the 3rd pin, forms 1 times put by R121, R66, R71, R72, C27 and C28
Amplify greatly, then export from the 1st pin and meet R66 and be connected to 8 pin accessory power outlet J5 the 3rd pin, be connected to the inner corresponding bass unit of earphone by 8 pin plugs and connecting line and sound; Digital signal processing chip U6 the 95th pin exports right high pitch and closes through electric capacity C9 lotus root, R 21 is connected to amplifier U 1 the 5th pin, form 1 times of amplifying circuit by R118, R24, R26, R27, C10 and C11 to amplify, meet R24 from the 7th pin output again and be connected to 8 pin accessory power outlet J5 the 6th pin, be connected to the inner corresponding voice unit of earphone by 8 pin plugs and connecting line and sound; Digital signal processing chip U6 the 89th pin exports right sound and closes through electric capacity C26 lotus root, R51 is connected to amplifier U2 the 5th pin, form 1 times of amplifying circuit by R120, R53, R55, R56, C27 and C28 to amplify, meet R53 from the 7th pin output again and be connected to 8 pin accessory power outlet J5 the 7th pin, be connected to the inner corresponding alto units of earphone by 8 pin plugs and connecting line and sound; Digital signal processing chip U6 the 83rd pin exports right bass and closes through electric capacity C46 lotus root, R78 is connected to amplifier U3 the 5th pin, form 1 times of amplifying circuit by R122, R80, R82, R83, C38 and C39 to amplify, meet R80 from the 7th pin output again and be connected to 8 pin accessory power outlet J5 the 8th pin, be connected to the inner corresponding bass unit of earphone by 8 pin plugs and connecting line and sound.
Signal after amplification is exported by output 8 core socket J5, the connecting line of eight core plugs connects J5, eight core connecting lines respectively connected common port (ground wire) totally eight groups of cores of the high pitch of left and right acoustic channels, middle pitch, bass and left-right signal, and are divided into left and right earphone cord in online earphone left and right, stage casing deconcentrator; Every limit four-core, comprises high pitch, middle pitch, bass and ground four lines, then enters in multiple sound unit earphone cavity, is connected to corresponding high pitch pronunciation unit, middle pitch pronunciation unit and bass pronunciation unit, and pronunciation unit is sounded and to be listened to for user.
The above; for the person of ordinary skill of the art; can make other various corresponding change and distortion according to the technical solution of the utility model and technical conceive, and all these change and be out of shape the protection range that all should belong to the utility model claim.
Claims (7)
1. have an earphone for active digital three frequency division system, comprise a housing, it is characterized in that, described housing is provided with audio signal input end mouth and Audio output port, the earphone pronunciation portion be connected with Audio output port; Active digital three frequency division system is provided with in described housing, described active digital three frequency division system comprises: main control module, digital signal input selection module, digital signal processing module, six road amplifier modules and provide the power module of power supply for above-mentioned all modules, described digital signal processing module is connected with described digital signal input selection module and six road amplifier modules, described digital signal input selection module is connected with audio signal input end mouth, and described six road amplifier modules are connected with Audio output port.
2. a kind of earphone with active digital three frequency division system according to claim 1, is characterized in that: described main control module connects described digital signal input selection module and described digital signal processing module.
3. a kind of earphone with active digital three frequency division system according to claim 1, is characterized in that: the described audio signal input end mouth be connected with digital signal input selection module is that coaxial digital signal input end mouth is or/and optical fiber and digital signal input port.
4. a kind of earphone with active digital three frequency division system according to claim 1, is characterized in that: described digital signal processing module is also connected with stereo analog input port.
5. a kind of earphone with active digital three frequency division system according to claim 1, is characterized in that: described Audio output port is 8 pin earphone output sockets.
6. a kind of earphone with active digital three frequency division system according to claim 1, is characterized in that: described earphone pronunciation portion comprises 8 pin plugs, 8 core earphone cords, earphone left and right deconcentrator and the left and right pronunciation unit earphone cavity that are connected successively.
7. a kind of earphone with active digital three frequency division system according to claim 1, is characterized in that: also comprise chargeable chip in described power module, and described housing also comprises USB interface, and described USB interface is connected with chargeable chip.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420456173.XU CN204272368U (en) | 2014-08-13 | 2014-08-13 | A kind of earphone with active digital three frequency division system |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420456173.XU CN204272368U (en) | 2014-08-13 | 2014-08-13 | A kind of earphone with active digital three frequency division system |
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| CN204272368U true CN204272368U (en) | 2015-04-15 |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110113690A (en) * | 2019-06-11 | 2019-08-09 | 安徽丰汇声学科技有限公司 | A kind of earphone cable and braiding processing method |
-
2014
- 2014-08-13 CN CN201420456173.XU patent/CN204272368U/en not_active Expired - Fee Related
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN110113690A (en) * | 2019-06-11 | 2019-08-09 | 安徽丰汇声学科技有限公司 | A kind of earphone cable and braiding processing method |
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