CN202261797U - System for testing reliability of piezoelectric ceramic loudspeaker - Google Patents
System for testing reliability of piezoelectric ceramic loudspeaker Download PDFInfo
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- CN202261797U CN202261797U CN2011203965766U CN201120396576U CN202261797U CN 202261797 U CN202261797 U CN 202261797U CN 2011203965766 U CN2011203965766 U CN 2011203965766U CN 201120396576 U CN201120396576 U CN 201120396576U CN 202261797 U CN202261797 U CN 202261797U
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Abstract
The utility model relates to a system for testing the reliability of a piezoelectric ceramic loudspeaker, which comprises a master control unit, an audio signal output unit, a modulation amplification unit, a voltage current detection unit and an impedance detection unit, wherein the signal input ends of the voltage current detection unit and the impedance detection unit are used for acquiring the corresponding to-be-tested signal of a unit to be tested; the detection signal output ends of the voltage current detection unit and the impedance detection unit are connected with the corresponding signal input end of the master control unit; the control signal output end of the master control unit is connected with the corresponding control signal input end of the audio signal output unit; the excitation signal output end of the audio signal output unit is connected with the corresponding signal input end of the modulation amplification unit; and the output end of the modulation amplification unit is connected with the corresponding excitation signal input end of the unit to be tested. The precision and the reliability of detection are improved by the system through detecting the characteristics of the multi-channel dynamic capacitive reactance and inductive reactance of the piezoelectric ceramic loudspeaker in the reliability testing process.
Description
Technical field
The utility model relates to a kind of reliability test system of loud speaker, a kind of reliability test system that is used for piezoelectric ceramic loudspeaker of saying so exactly.
Background technology
Portable type electronic product such as computer, mobile phone has become the present people necessary part of living, and loud speaker plays an important role as the critical component in these electronic products.Loud speaker is commonly called as and is loudspeaker, and it is a kind of electro-acoustic element that converts electrical energy into acoustic energy.The kind of loud speaker is a lot, though their working method is different, finally all is to promote ambient air through producing mechanical oscillation, thereby makes air dielectric produce the conversion that fluctuation realizes " electricity-Li-sound ".Widely applying the loud speaker aspect high-fidelity music center now all is dynamic speaker mostly.Several kinds of other comparatively common electrostatic in addition, flat, piezoelectric ceramic pieces etc.
Wherein, piezoelectric ceramic piece is to utilize piezoelectric effect work, not only can make sounding component but also can receive the element of sound.And it is very cheap, and the sounding component on the birthday card is exactly it.Piezoelectric ceramic piece is the piezoelectric ceramic that on the shape copper soleplate of garden, has applied the about 1mm of a bed thickness, is coated with silver layer at ceramic surface deposition one deck again, and being coated with silver layer and copper soleplate is exactly its two electrodes.Piezoelectric ceramic has a marvellous characteristic-piezoelectric effect: as with its bending, the xenogenesis electric charge will appear in its surface, and like back-flexing, the polarity of electric charge also can be opposite.If on two electrodes of piezoelectric ceramic piece, apply certain voltage, it will bend, and when voltage direction changed, crooked direction also changed thereupon.Utilize piezoelectric effect; Had a kind of sound-; The dual-purpose device of electroacoustic conversion can be worked as microphone and use: to the piezoelectric ceramic piece speech, made it receive the vibration of sound wave and bending before and after taking place; Certainly people's eyes are differentiated to go out this bending, just have audio voltage at two electrodes of piezoelectric ceramic piece and export.On the contrary, be added in the two poles of the earth of piezoelectric ceramic piece to certain audio voltage, because the polarity of audio voltage constantly changes with size, piezoelectric ceramic piece will produce corresponding bending motion, promotes air and forms sound, and at this time, it has become loudspeaker again.
Piezoelectric ceramic loudspeaker is a kind of novel electro-acoustic element that is used widely in recent years; But remain blank to the dedicated reliable property testing equipment of this novel electro-acoustic element; Traditional loud speaker reliability testing equipment generally only detects the speaker operation change in current, and can not differentiate the failure phenomenon that causes owing to piezoelectric ceramic capacitive reactance ANOMALOUS VARIATIONS.
At present, ultrathin piezoelectric ceramic loudspeaker is mainly used in some novel portable type electronic products, and its reliability testing problem needs to be resolved hurrily.
The piezoelectric ceramic loudspeaker reliability test what will accomplish is in the time of standard code; The piezoelectric ceramic loudspeaker of reception test is applied the power audio signal of prescribed strength; And in whole process of the test, the electrical property that dynamically detects each piezoelectric ceramic loudspeaker in real time changes.For common coil-moving speaker, coil presents a fixing resistance characteristic, and the variation with the audio signal frequency that is applied does not change, so, in traditional loud speaker reliability test, only detect the open circuit of loud speaker and the extreme case of short circuit.And piezoelectric ceramic loudspeaker appears is the capacitive reactance characteristic of an electric capacity; Its capacitive reactance changes along with the variation of the audio signal frequency that applies; Its variable quantity directly has influence on the output audio characteristic of loud speaker, therefore, has only overall process to detect the capacitive reactance index of piezoelectric ceramic loudspeaker in real time; Compare with the Ideal Characteristics curve, could determine the result of the test of piezoelectric ceramic loudspeaker veritably.
Summary of the invention
The purpose of the utility model is to piezoelectric ceramic loudspeaker and traditional diverse structure of loud speaker; Electrical property characteristics etc.; Can't test its reliability problems at present, propose a kind of through detecting the system that voltage, electric current and resistance detect the piezoelectric ceramic loudspeaker reliability.
The technical scheme of the utility model is:
A kind of reliability test system that is used for piezoelectric ceramic loudspeaker; Comprise main control unit, audio signal output unit, modulation amplifying unit, measured piece unit, electric current and voltage detecting unit and impedance detection unit; The signal input part of described electric current and voltage detecting unit and impedance detection unit is gathered the corresponding measured signal of measured piece unit as the signals collecting end of reliability test system; The detection signal output of electric current and voltage detecting unit and impedance detection unit links to each other with the respective signal input of main control unit; The control signal output ends of main control unit links to each other with the corresponding control signal input of audio signal output unit; The pumping signal output of audio signal output unit links to each other with the respective signal input of modulation amplifying unit, and the output of modulation amplifying unit links to each other with the corresponding pumping signal input of measured piece unit.
The main control unit of the utility model is connected with memory cell, and the signal input part of main control unit connects with the corresponding output of keying unit, and the shows signal output of main control unit links to each other with the corresponding input of display unit.
The audio signal output unit of the utility model comprises a plurality of sources of sound and variable connector one; A plurality of sources of sound are connected with the respective signal input of variable connector one; The signal input end of variable connector one is connected with the respective signal output of main control unit, and the output of variable connector one links to each other with the respective signal input of modulation amplifying unit.
A plurality of sources of sound of the utility model comprise external sound source, sinusoidal wave source of sound and square wave source of sound, the sine wave that described sinusoidal wave source of sound and square wave source of sound are exported through frequency control module control and the frequency of square wave, sweep speed and frequency range.
The modulation amplifying unit of the utility model comprises D/A adjustment module, multiplier, variable connector two, a N power amplifier and N group DPDT diverter switch; The signal input end of the D/A adjustment module of control multiplier links to each other with the respective signal output of main control unit; The reference input of multiplier links to each other with the corresponding pumping signal output of audio signal output unit; The signal input end of D/A adjustment module links to each other with the control signal output ends of multiplier; The signal output part of the multiplier of D/A adjustment module control links to each other with the respective signal input of variable connector two; The signal output part of variable connector two connects with corresponding N power amplifier, and each power amplifier is connected with each piezoelectric ceramic loudspeaker through the corresponding DPDT diverter switch in each road respectively, and applies corresponding pumping signal.
The electric current and voltage detecting unit of the utility model comprises plurality of voltages sampling module, multichannel current sampling module, voltage-programmed amplification module, current-programmed amplification module, variable connector four and A/D modular converter one; Each signal input part of plurality of voltages sampling module is connected with the output line road of each power amplifier respectively; Each signal input part of multichannel current sampling module is connected with the non-earth terminal of the current sampling resistor Rs of each piezoelectric ceramic loudspeaker series connection respectively; The signal output part of plurality of voltages sampling module is connected with the respective signal input of voltage-programmed amplification module; The signal output part of multichannel current sampling module is connected with the respective signal input of current-programmed amplification module; The signal output part of voltage-programmed amplification module and current-programmed amplification module is connected with the corresponding input of variable connector four respectively; The signal output part of variable connector four is connected with the signal input part of A/D modular converter one, and the signal output part of A/D modular converter one is connected with the respective signal input of main control unit.
The impedance detection unit of the utility model comprises impedance detection module, low frequency sine signal source, voltage/current decomposing module, variable connector five, variable connector three, program control amplification module, resolution of vectors module and A/D modular converter two; The impedance detection unit module switches to corresponding loud speaker two through each road DPDT diverter switch timesharing and brings in and carry out impedance detection; Its medium and low frequency sine signal source provides pumping signal to drive loud speaker; The voltage/current decomposing module is responsible for gathering voltage/current signals as the signals collecting end; The voltage of voltage/current decomposing module, current signal output end are connected with the respective signal input of variable connector five; The output of variable connector five is connected in series program control amplification module and resolution of vectors module successively; Each signal output part of resolution of vectors module is connected with the respective signal input of variable connector three; The signal output part of variable connector three is connected with the respective signal input of A/D modular converter two; The signal output part of A/D modular converter two is connected with the signal input part of impedance detection module; The two-way connection of control signal end of the control signal end of impedance detection module and main control unit, a plurality of control signal output ends of impedance detection module connect the respective signal input of low frequency sine signal source, voltage/current decomposing module, variable connector five, variable connector three, program control amplification module and resolution of vectors module respectively.
The low frequency sine signal source of the utility model is connected in series driver module and source resistance with organize between the DPDT diverter switches more.
The reliability test system of the utility model is supplied power by power module, comprises digital power, analog power and power amplifier power supply.
The beneficial effect of the utility model:
Native system is made up of the power signal source of a plurality of passages; The signal programmable; In the time period of setting, drive pressure electroceramics speaker operation, the capacitive reactance in the course of the work of simultaneity factor detection at any time piezoelectric ceramic loudspeaker changes; According to this variation, judge whether the audio work characteristic of piezoelectric ceramic loudspeaker meets.In the reliability test process,, the precision and the reliability that detect have been improved through the dynamic capacitive reactance of the multichannel of piezoelectric ceramic loudspeaker, induction reactance Characteristics Detection.Along with the increasing that country drops into the electroacoustic industry, the consumption of this project product will further increase, and promote this product and realize production domesticization, have the good social economic benefit.
The utility model is integrated piezoelectric ceramic loudspeaker performance measurement and reliability test are on an equipment; Because traditional loud speaker reliability-test equipment does not have the function that the piezoelectric ceramic loudspeaker performance is detected in real time; So can not differentiate the failure phenomenon that the reliability test process causes owing to piezoelectric ceramic capacitive reactance ANOMALOUS VARIATIONS, this project will effectively address this problem.
The utility model has adopted synthetic sine wave and the square-wave signal source of DDS numeral, and a plurality of passages of generation that can be accurate, the audio frequency swept-frequency signal of multifrequency nature with respect to the signal source of analog form, have more precision, stable, controlled characteristics.
On the utility model systems soft ware the data in the reliability test process have been carried out analyzing and processing, and shown intuitively, also can be transferred to PC and do further processing through the RS-232/RS-485 communication interface through lcd screen.
Description of drawings
Fig. 1 is the utility model theory diagram.
Embodiment
Below in conjunction with accompanying drawing and embodiment the utility model is further described.
As shown in Figure 1, the utility model is a kind of multichannel loud speaker reliability test system, comprises main control unit, audio signal output unit, modulation amplifying unit, measured piece unit, electric current and voltage detecting unit and impedance detection unit.
The audio signal output unit of the utility model comprises a plurality of sources of sound and variable connector one; The modulation amplifying unit comprises D/A adjustment module, multiplier, variable connector two, a plurality of power amplifier and organizes the DPDT diverter switch more; The electric current and voltage detecting unit comprises plurality of voltages sampling module, multichannel current sampling module, voltage-programmed amplification module, current-programmed amplification module, variable connector four and A/D modular converter one; The impedance detection unit comprises impedance detection module, low frequency sine signal source, voltage/current decomposing module, variable connector five, variable connector three, program control amplification module, resolution of vectors module and A/D modular converter two.
During work; Main control unit produces satisfactory audio frequency swept-frequency signal through the audio signal output unit; Be applied on each loud speaker that is connected on the power amplifier of N road through variable connector; Operating current on the real-time acquisition test loud speaker of multichannel sampling unit, and judge loud speaker whether overcurrent or open fault.
Impedance measuring unit is through the two ends of N group DPDT diverter switch connection tested speaker, the impedance state of timesharing scanning survey tested speaker.
The test requirements document of this platform should meet the international loud speaker testing standard of EIA-426-B; The performance characteristics that meets ultrathin piezoelectric ceramic loudspeaker again; Therefore, the research and development of this project are integrated piezoelectric ceramic component test macro, multichannel, polymorphic type test signal origin system and reliability test software synthesis system; Form one professional extremely strong, the comprehensive test equipment of high efficiency, high reliability.
1, ultrathin piezoelectric ceramic loudspeaker reliability test what will accomplish is in the time of standard code; The piezoelectric ceramic loudspeaker of reception test is applied the power audio signal of prescribed strength, and in whole process of the test, dynamically detect the electrical property variation of each piezoelectric ceramic loudspeaker in real time; For common coil-moving speaker; Coil presents a fixing resistance characteristic, and the frequency change with the audio signal that is applied does not change, so; In traditional loud speaker reliability test, only need detect the open circuit of loud speaker and the extreme case of short circuit.And piezoelectric ceramic loudspeaker appears is the capacitive reactance characteristic of an electric capacity; It changes and changes along with the audio signal frequency that applies; Its variable quantity directly has influence on the output audio characteristic of loud speaker, therefore, has only overall process to detect the capacitive reactance index of piezoelectric ceramic loudspeaker in real time; Compare with the Ideal Characteristics curve, could determine the result of the test of piezoelectric ceramic loudspeaker veritably.
2, aspect the life tests of loud speaker; Traditional loud speaker life test appearance generally is different impedances and the power requirement to the test loud speaker; Provide a specific stimulus; In whole process of the test, except to possibly detecting the damage of test apparatus because of the loud speaker short circuit, the unit for electrical property parameters of loud speaker in entire test changed do not carry out real-time detection; And ultrathin piezoelectric ceramic loudspeaker and traditional moving-coil speaker have very big difference.They show as a capacitive load, rather than resistive load.Stimulus different is done the time spent, and along with the variation of its capacitive load, its equiva lent impedance is also constantly changing, and is therefore also just more harsh to the requirement of stimulus under the situation of this load, need meet two requirements:
(1) one can be satisfied and loads on whole audio region to be close to short circuit and near the reliable swept signal source of the variable condition of open circuit; The frequency of signal source and amplitude satisfy the desired precision of the international loud speaker testing standard of EIA-426-B;
(2) in entire test, can the entire test of ultrathin piezoelectric ceramic loudspeaker be detected, and the test data in the whole process is carried out record, analyze.
Above-mentioned several aspect, the multichannel piezoelectric ceramic loudspeaker reliability experiment instrument of the utility model is a multichannel, multi-function power testing equipment.Built-in sine involves the square wave swept signal generator; Are furnished with two outer signal input channels in addition; Multichannel piezoelectric ceramic loudspeaker reliability experiment instrument can fully satisfy the middle low power piezoelectric ceramic loudspeaker communicates by letter with the specification requirement of receiver ageing test with various, and its technical indicator meets national correlation technique standard.
Basic technical indicator is following:
1. interface section
Maximum can insert way: the 20 tunnel, divide two groups, and passage 1-10 is one group, and passage 11-20 is another group, and each is organized test parameters and can independently be provided with.
Ageing test time: 0.1-999.9h can set arbitrarily.
Failure free time: the 20 road monitor simultaneously, write down automatically and show.
State is judged: open circuit, short circuit or capacitive reactance excessive variation.
Failure warning: 20 paths of LEDs on the panel show the faulty channel position.
Man-machine interface: 320 * 240 liquid crystal display screens show, keyboard input, Chinese and English interface.
RCI: computer remote control, RS-485 can monitor the operating state of many power test appearance simultaneously, and the maximum control distance is greater than 100 meters.
2. signal generator part
Sine wave signal generator:
Test frequency scope: 20Hz-20,000Hz
Frequency accuracy: ± 0.01%
Frequency stability: be superior to 60ppm
Total harmonic distortion (THD) :≤0.5% 1kHz
Can select the frequency sweep function: every octave 96 points, the frequency sweep time is optional
3. outer signal source input:
Two-way BNC input can be selected through panel.
4. power amplifier part:
20 tunnel independent power amplifiers
Every road peak power output: 15W
Maximum gross output: >=300W
Frequency response: 20-20,000Hz (± 1dB)
Total harmonic distortion (THD) :≤0.01% 1W
Output impedance :≤0.15 Ω
Load impedance: 4-500 Ω
Adjustable range of output voltage: 0.5-10V (degree of regulation is 0.1V)
Other:
Operating voltage: ~ 220V ± 10%, 2A
Operating ambient temperature: 5-40 ℃
Storage condition temperature: 0-60 ℃
Overall dimension: 483mm * 445mm * 190mm standard 19 " cabinet of putting on the shelf.
The utility model does not relate to all identical with the prior art prior art that maybe can adopt of part to be realized.
Claims (9)
1. reliability test system that is used for piezoelectric ceramic loudspeaker; It is characterized in that it comprises main control unit, audio signal output unit, modulation amplifying unit, measured piece unit, electric current and voltage detecting unit and impedance detection unit; The signal input part of described electric current and voltage detecting unit and impedance detection unit is gathered the corresponding measured signal of measured piece unit as the signals collecting end of reliability test system; The detection signal output of electric current and voltage detecting unit and impedance detection unit links to each other with the respective signal input of main control unit; The control signal output ends of main control unit links to each other with the corresponding control signal input of audio signal output unit; The pumping signal output of audio signal output unit links to each other with the respective signal input of modulation amplifying unit, and the output of modulation amplifying unit links to each other with the corresponding pumping signal input of measured piece unit.
2. the reliability test system that is used for piezoelectric ceramic loudspeaker according to claim 1; It is characterized in that described main control unit is connected with memory cell; The signal input part of main control unit connects with the corresponding output of keying unit, and the shows signal output of main control unit links to each other with the corresponding input of display unit.
3. the reliability test system that is used for piezoelectric ceramic loudspeaker according to claim 1; It is characterized in that described audio signal output unit comprises a plurality of sources of sound and variable connector one; A plurality of sources of sound are connected with the respective signal input of variable connector one; The signal input end of variable connector one is connected with the respective signal output of main control unit, and the output of variable connector one links to each other with the respective signal input of modulation amplifying unit.
4. the reliability test system that is used for piezoelectric ceramic loudspeaker according to claim 3; It is characterized in that described a plurality of source of sound comprises external sound source, sinusoidal wave source of sound and square wave source of sound, the sine wave that described sinusoidal wave source of sound and square wave source of sound are exported through frequency control module control and the frequency of square wave, sweep speed and frequency range.
5. the reliability test system that is used for piezoelectric ceramic loudspeaker according to claim 1; It is characterized in that described modulation amplifying unit comprises D/A adjustment module, multiplier, variable connector two, a N power amplifier and N group DPDT diverter switch; The signal input end of the D/A adjustment module of control multiplier links to each other with the respective signal output of main control unit; The reference input of multiplier links to each other with the corresponding pumping signal output of audio signal output unit; The signal input end of D/A adjustment module links to each other with the control signal output ends of multiplier; The signal output part of the multiplier of D/A adjustment module control links to each other with the respective signal input of variable connector two; The signal output part of variable connector two connects with corresponding N power amplifier, and each power amplifier is connected with each piezoelectric ceramic loudspeaker through the corresponding DPDT diverter switch in each road respectively, and applies corresponding pumping signal.
6. the reliability test system that is used for piezoelectric ceramic loudspeaker according to claim 1; It is characterized in that described electric current and voltage detecting unit comprises plurality of voltages sampling module, multichannel current sampling module, voltage-programmed amplification module, current-programmed amplification module, variable connector four and A/D modular converter one; Each signal input part of plurality of voltages sampling module is connected with the output line road of each power amplifier respectively; Each signal input part of multichannel current sampling module is connected with the non-earth terminal of the current sampling resistor Rs of each piezoelectric ceramic loudspeaker series connection respectively; The signal output part of plurality of voltages sampling module is connected with the respective signal input of voltage-programmed amplification module; The signal output part of multichannel current sampling module is connected with the respective signal input of current-programmed amplification module; The signal output part of voltage-programmed amplification module and current-programmed amplification module is connected with the corresponding input of variable connector four respectively; The signal output part of variable connector four is connected with the signal input part of A/D modular converter one, and the signal output part of A/D modular converter one is connected with the respective signal input of main control unit.
7. the reliability test system that is used for piezoelectric ceramic loudspeaker according to claim 1; It is characterized in that described impedance detection unit comprises impedance detection module, low frequency sine signal source, voltage/current decomposing module, variable connector five, variable connector three, program control amplification module, resolution of vectors module and A/D modular converter two; The impedance detection unit module switches to corresponding loud speaker two through each road DPDT diverter switch timesharing and brings in and carry out impedance detection; Its medium and low frequency sine signal source provides pumping signal to drive loud speaker; The voltage/current decomposing module is responsible for gathering voltage/current signals as the signals collecting end; The voltage of voltage/current decomposing module, current signal output end are connected with the respective signal input of variable connector five; The output of variable connector five is connected in series program control amplification module and resolution of vectors module successively; Each signal output part of resolution of vectors module is connected with the respective signal input of variable connector three; The signal output part of variable connector three is connected with the respective signal input of A/D modular converter two; The signal output part of A/D modular converter two is connected with the signal input part of impedance detection module, and two-way connection of control signal end of the control signal end of impedance detection module and main control unit, a plurality of control signal output ends of impedance detection module connect the respective signal input of low frequency sine signal source, voltage/current decomposing module, variable connector five, variable connector three, program control amplification module and resolution of vectors module respectively.
8. the reliability test system that is used for piezoelectric ceramic loudspeaker according to claim 7 is characterized in that described low frequency sine signal source is connected in series driver module and source resistance with organize between the DPDT diverter switches more.
9. the reliability test system that is used for piezoelectric ceramic loudspeaker according to claim 1 is characterized in that described reliability test system supplied power by power module, comprises digital power, analog power and power amplifier power supply.
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011203965766U CN202261797U (en) | 2011-10-18 | 2011-10-18 | System for testing reliability of piezoelectric ceramic loudspeaker |
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| Application Number | Priority Date | Filing Date | Title |
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| CN2011203965766U CN202261797U (en) | 2011-10-18 | 2011-10-18 | System for testing reliability of piezoelectric ceramic loudspeaker |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102970646A (en) * | 2012-11-06 | 2013-03-13 | 西安工程大学 | Loudspeaker abnormal sound detection circuit device and detection method based on constant current source power amplification |
| CN103607686A (en) * | 2013-10-30 | 2014-02-26 | 奇瑞汽车股份有限公司 | Motor-vehicle sound-device monitoring device and method |
| CN106998524A (en) * | 2017-06-07 | 2017-08-01 | 盐城工学院 | Loudspeaker test device and loudspeaker test equipment |
-
2011
- 2011-10-18 CN CN2011203965766U patent/CN202261797U/en not_active Expired - Fee Related
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN102970646A (en) * | 2012-11-06 | 2013-03-13 | 西安工程大学 | Loudspeaker abnormal sound detection circuit device and detection method based on constant current source power amplification |
| CN102970646B (en) * | 2012-11-06 | 2015-06-24 | 西安工程大学 | Loudspeaker abnormal sound detection circuit device and detection method based on constant current source power amplification |
| CN103607686A (en) * | 2013-10-30 | 2014-02-26 | 奇瑞汽车股份有限公司 | Motor-vehicle sound-device monitoring device and method |
| CN103607686B (en) * | 2013-10-30 | 2017-05-10 | 奇瑞汽车股份有限公司 | Motor-vehicle sound-device monitoring device and method |
| CN106998524A (en) * | 2017-06-07 | 2017-08-01 | 盐城工学院 | Loudspeaker test device and loudspeaker test equipment |
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