CN205793346U - A kind of towards earphone/headset loudspeaker broken string and short-circuit detecting circuit - Google Patents
A kind of towards earphone/headset loudspeaker broken string and short-circuit detecting circuit Download PDFInfo
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- CN205793346U CN205793346U CN201620490503.6U CN201620490503U CN205793346U CN 205793346 U CN205793346 U CN 205793346U CN 201620490503 U CN201620490503 U CN 201620490503U CN 205793346 U CN205793346 U CN 205793346U
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Abstract
This utility model relates to a kind of towards earphone/headset loudspeaker broken string and short-circuit detecting circuit, including MCU, measures signal bleeder circuit and high-frequency signal amplification protection circuit；The detection control signal outfan of described MCU amplifies protection circuit with high-frequency signal and is connected, and the voltage signal inputs of MCU is connected with high-frequency signal amplification protection circuit by measuring signal bleeder circuit；Described high-frequency signal amplifies protection circuit and is located at earphone/between headset loudspeaker and audio signal output circuit.This utility model, towards wireless tranceiver, mobile phone, electro-acoustic playback equipment, can detect the broken string/short trouble of earphone/headset loudspeaker in time, in order to avoid impact uses.This utility model low cost, the advantages such as circuit is simple, practical, reliable.
Description
Technical field
This utility model relates to transmitter receiver, mobile phone, and electro-acoustic propagates broadcasting field, and earphone/headset loudspeaker break
Line and short-circuit detecting circuit, a kind of towards radio receiver, electro-acoustic propagates playback equipment
The earphone of (device)/headset loudspeaker broken string and short-circuit detecting circuit.
Background technology
In modern life, along with the development of electronic technology, wireless tranceiver, mobile phone, electro-acoustic
Play System application is more and more extensive.People when using the transmission playback equipment such as transmitter receiver/mobile phone/radio,
Loudspeaker earphone/headset to be used, and when its broken string or short circuit, user can not perceive in time, especially exists
If during start earphone/headset loudspeaker have broken string or short circuit occur, can not receive after start the most always sound or
Can't hear broadcasting sound, can't find in time, affect wireless tranceiver, mobile phone, electro-acoustic Play System
Use.Therefore be badly in need of a kind of can with test earphone/headset loudspeaker have broken string or the detection device of short circuit.
Utility model content
For above-mentioned technical deficiency, the purpose of this utility model provide a kind of towards earphone/headset loudspeaker broken string with
Short-circuit detecting circuit.This circuit is not affecting in the case of earphone/headset loudspeaker normally use, and can examine in time
Measure earphone/headset loudspeaker broken string and short circuit, it is provided that the foundation that prompting is reported to the police.
This utility model be the technical scheme is that a kind of towards earphone/headset loudspeaker for achieving the above object
Broken string and short-circuit detecting circuit, including MCU, measure signal bleeder circuit and high-frequency signal amplification protection circuit；
The detection control signal outfan of described MCU amplifies protection circuit with high-frequency signal and is connected, the voltage signal of MCU
Input is connected with high-frequency signal amplification protection circuit by measuring signal bleeder circuit；Described high-frequency signal is put
Big protection circuit is located at earphone/between headset loudspeaker and audio signal output circuit.
Described measurement signal bleeder circuit includes that the detection control signal outfan of two divider resistance: MCU passes through
Divider resistance R1 amplifies protection circuit with high-frequency signal and is connected, also by divider resistance R3 ground connection.
Described high-frequency signal amplifies protection circuit and includes divider resistance R2, electric capacity C1 and amplifier；Audio signal
The outfan of output circuit passes sequentially through amplifier, electric capacity C1 is connected with earphone/headset loudspeaker input, ear
Machine/headset loudspeaker input passes through divider resistance R2 ground connection.
When for DC detecting, the detection control signal outfan of MCU passes sequentially through audion Tr1, resistance
After R4, then with divider resistance R2 and the Node connectedness of electric capacity C1, be also connected with divider resistance R1；Described
The detection control signal outfan of MCU is connected with audion Tr1 base stage, the emitter stage of audion Tr1 and power supply
Connecting, colelctor electrode is connected with resistance R4.
When being used for exchanging detection, the detection control signal outfan of MCU is defeated by electric capacity C2 and amplifier
Enter end to connect.
When being used for exchanging detection, measure and be connected with guarantor between the voltage signal inputs of signal bleeder circuit and MCU
Protection circuit；Described protection circuit is diode D1, D2 of two series connection；Divider resistance R1 and divider resistance
The node of R3 is connected with negative pole, the positive pole of diode D2 of diode D1, the negative pole of diode D2 and power supply
Connect, the plus earth of diode D1.
When being used for exchanging detection, between the voltage signal inputs of protection circuit and MCU, it is connected with halfwave rectifier electricity
Road；Described half-wave rectifying circuit includes diode D3, resistance R4 and electric capacity C3；Knot between diode D1, D2
Point is connected with diode D3 positive pole, and diode D3 negative pole is connected with the voltage signal inputs of MCU, leads to the most respectively
Cross resistance R4, electric capacity C3 ground connection
This utility model has the advantages that and advantage:
1. this utility model is towards wireless tranceiver, mobile phone, electro-acoustic playback equipment, can detect in time
Go out the broken string/short trouble of earphone/headset loudspeaker, in order to avoid impact uses.
2. the advantages such as this utility model has low cost, and circuit is simple, practical, reliable.
Measurement signal bleeder circuit the most of the present utility model can reduce the external circuit impact on MCU.
High-frequency signal the most of the present utility model amplifies protection circuit can not affect usual voice output performance
In the case of, the broken string for earphone/headset loudspeaker provides voltage signal.
Protection circuit the most of the present utility model is prevented from overvoltage and negative voltage loads and inputs to the A/D of MCU
Port；Half-wave rectifying circuit can provide a metastable detection signal and shorten response time.
6. this utility model can use direct current and exchange two kinds of detection modes, uses DC detecting mode in inspection
Detection sound can be heard during survey, but circuit and method are simple；Detection can be can't hear when using exchange detection mode
Sound, is all capable of not affecting earphone/headset loudspeaker broken string/short circuit in the case of usual voice output performance
Fault detect.
Accompanying drawing explanation
Fig. 1 is this utility model circuit diagram when DC detecting；
Fig. 2 is this utility model circuit diagram when exchange detection；
Fig. 3 is the process chart of Dc bias mode of the present utility model；
Fig. 4 is the process chart of AC bias mode of the present utility model；
Fig. 5 is the data sampling sequential chart of AC bias mode of the present utility model.
Detailed description of the invention
Below in conjunction with the accompanying drawings and this utility model is described in further detail by embodiment.
This utility model provides DC-AC two ways and is applicable to say the voice transfer playback equipments such as machine/mobile phone
The testing circuit of loudspeaker earphone/headset broken string and short circuit.
As it is shown in figure 1, when for DC detecting:
This utility model includes MCU, audion Tr1, resistance R4, measures signal bleeder circuit and high-frequency signal
Amplify protection circuit.This utility model is at original earphone/headset loudspeaker input and audio signal output circuit
Between connect high-frequency signal amplify protection circuit；MCU detection control signal outfan pass sequentially through audion Tr1,
Resistance R4 amplifies protection circuit with measurement signal bleeder circuit and high-frequency signal and is connected；High-frequency signal amplifies protection
Circuit is connected with the analog signals input of MCU by measuring signal bleeder circuit.
Single-chip microcomputer (MCU) is provided with detection control signal outfan (DX01) and analog signals input (DXm).
Detection control signal outfan (DX01) provides low level signal [PLS1], and detection control signal controls switch
Audion Tr1 turns on, supply voltage VCC by Tr1, make current-limiting resistance dividing potential drop R4 and divider resistance R2 with
Earphone/headset loudspeaker (SP) internal resistance R5 stream has electric current, and earphone/headset loudspeaker voltage passes through divider resistance R1
Obtaining voltage signal [AD1] with divider resistance R3, its voltage signal is input to single-chip microprocessor MCU and measures input
(DXm), measure magnitude of voltage, can determine whether that earphone/headset loudspeaker (SP) there occurs broken string or short circuit.
As in figure 2 it is shown, when being used for exchanging detection:
This utility model includes that MCU, electric capacity C2, high-frequency signal amplify protection circuit, measure signal dividing potential drop electricity
Road, protection circuit and half-wave rectifying circuit.This utility model is at original earphone/headset loudspeaker input and sound
Frequently connect high-frequency signal between signal output apparatus and amplify protection circuit；MCU detection control signal outfan passes through
Electric capacity C2 amplifies protection circuit with high-frequency signal and is connected；High-frequency signal amplifies protection circuit and passes sequentially through measurement letter
Number bleeder circuit, protection circuit, half-wave rectifying circuit are connected with the analog signals input of MCU.
Single-chip microcomputer (MCU) is provided with detection control signal outfan (DX02) and analog signals input (DXm).
Detection control signal outfan (DX02) provides exchange low and high level signal [PLS2], through capacitance C2,
Output is amplified again, at parallel resistance R2 and earphone/headset loudspeaker (SP) internal resistance R5 through audio frequency power amplifier (AMP)
Stream have electric current produce detection voltage, the detection voltage of earphone/headset loudspeaker (SP) by divider resistance R1 with
The dividing potential drop of divider resistance R3 and protection diode (D1, D2), half-wave rectifying circuit (D3, R4, C3)
Obtain the voltage signal [AD2] that detection is measured, be input to single-chip microprocessor MCU and measure input (DXm), controlling
Measure the magnitude of voltage of earphone/headset loudspeaker (SP) between signal output part (DX02) output high period, can sentence
Disconnected earphone/headset loudspeaker (SP) there occurs broken string or short circuit.
Control signal of the present utility model is passed through fixed resistance and fixed direct current or low-frequency electric current is added to
Earphone/headset loudspeaker, measure this exporting change signal, and its measured value voltage is compared with fixed threshold value, according to
It is to have exceeded threshold value to be also less than threshold value, it is judged that the broken string of its measured value test earphone/headset loudspeaker and short circuit
Method.This utility model is applicable to include transmitter receiver, mobile phone, and electronic speech propagates the cable voices such as player
Device.
As it is shown on figure 3, when for DC detecting, detection method 1 (Dc bias mode) is specific as follows:
MCU provides DXo1 control signal makes Tr1 turn on, and Vcc is added to divider resistance R2 by current limliting dividing potential drop R4
On the circuit in parallel with earphone/headset loudspeaker (R3 resistance), its voltage is by divider resistance R1 and dividing potential drop electricity
Resistance R3 obtains voltage signal [AD1] and is input to A/D input pin DXm, MCU detection its magnitude of voltage of DXm of MCU,
The magnitude of voltage detected according to it contrasts with broken string threshold value/short-circuit threshold value, it is judged that whether it breaks with short
Road.
1, threshold range is first determined:
Detection magnitude of voltage is as follows:
Vdxm={ (R2*R5/ (R2+R5) }/{ R4+ (R2*R5)/(R2+R5) } * Vcc
*R3/(R1+R3)
R4 be 100～200 Ω, R2 be 10K Ω～30K Ω, and R5 is between 4～160 Ω.
Time normal, Vdxm1 about=(R5/ (R4+R5) * Vcc*R3/ (R1+R3) (unit: V)
During broken string, Vdxm2 about=(R2/ (R4+R2) * Vcc*R3/ (R1+R3) (unit: V)
During short circuit, Vdxm0 about=0 (unit: V)
Broken string threshold value=between less than Vdxm1 more than Vdxm2, it may be assumed that Vdxm2 <broken string threshold value < Vdxm1；
Short-circuit threshold value=between less than Vdxm2 more than 0, it may be assumed that 0 < short-circuit threshold value < Vdxm2.
Its threshold value that breaks > short-circuit threshold value.
2, the resistance of various earphones/headset loudspeaker is substituted into above-mentioned formula respectively, choose and meet various ear simultaneously
The broken string threshold value of machine/headset loudspeaker and short-circuit threshold value；Its interrupt line threshold value need to be less than various earphones/headset loudspeaker
Magnitude of voltage during broken string；Short-circuit threshold value need to be slightly larger than zero.
Generally the resistance of earphone/headset loudspeaker is 8 Ω.
R5 is 8 Ω, R4=100 Ω, R2=20k Ω, during Vcc=3V, R1=100k Ω, R3=100k Ω:
Time normal, Vdxm1 about=(R5/ (R4+R5) * Vcc*R3/ (R1+R3)
=8/ (108) * 3*0.5=111mV=V1
During broken string, Vdxm2 about=(R2/ (R4+R2) * Vcc*R3/ (R1+R3)
=20/20.1*3*0.5=1.49V=V2
Short circuit time, Vdxm0 about=0V
Resistance in view of special headphones/headset loudspeaker is 100 Ω,
R5 is 100 Ω, R4=100 Ω, R2=20k Ω, during Vcc=3V, R1=100k Ω, R3=100k Ω:
Time normal, Vdxm1 about=(R5/ (R4+R5) * Vcc*R3/ (R1+R3)
=100/ (200) * 3*0.5=750mV=V3
During broken string, Vdxm2 about=(R2/ (R4+R2) * Vcc*R3/ (R1+R3)
=20/20.1*3*0.5=1.49V=V4
Short circuit time, Vdxm0 about=0V
At this moment broken string threshold value setting=1.2V；I.e. set broken string threshold value < V2 and broken string threshold value < V4.
Short-circuit threshold value setting=50mV；I.e. set 0 < short-circuit threshold value < V3.
Magnitude of voltage ＞ 1.2V detected during earphone/headset loudspeaker broken string, time normal, detect that magnitude of voltage exists 50mV
And <between 1.2V, during short circuit, magnitude of voltage < 50mV detected.
As shown in Figure 4, when being used for exchanging detection, detection method 2 (AC bias mode) is specific as follows:
MCU provides DX02 and exchanges high low control signal, is exported by capacitance C1 and audio frequency power amplifier AMP
Divider resistance R2 and earphone/headset loudspeaker (R 5 resistance) upstream have electric current to produce detection voltage, and it detects electricity
The pressure dividing potential drop by divider resistance R1 Yu divider resistance R3, protection diode D2 and protection diode D1 are
In order to prevent overvoltage or negative voltage to be added to the A/D port [DXm] of MCU, through half-wave rectifying circuit (D3,
R4, C3) obtain detecting signal [AD2], MCU detects the electricity of signal [AD2] between DX02 output high period
Pressure value, the magnitude of voltage detected according to it contrasts with broken string threshold value/short-circuit threshold value, it is judged that whether it breaks
With short circuit.
As it is shown in figure 5, between DXo2 output signal high period, MCU is taked by A/D port [DXm]
Detection signal [AD2] obtains detecting magnitude of voltage, for improving the accuracy of detection magnitude of voltage, takes at a DXo2
Repeatedly take to detect signal [AD2] between output signal high period to obtain detecting magnitude of voltage.For improving inspection further
Survey the accuracy of magnitude of voltage, repeatedly take to detect signal [AD2] between multiple DXo2 output signal high period
Obtain detecting magnitude of voltage, be filtered the multiple detection magnitudes of voltage detected processing.
1, threshold range is first determined:
I is the output electric current of the i.e. amplifier of audio frequency power amplifier, and detection magnitude of voltage is as follows:
Vdxm={ (R2*R 5)/(R2+R 5) } * I*R3/ (R1+R3)
R2 is 1K Ω～10K Ω, and R5 is between 4～160 Ω.
Time normal, Vdxm1 about=R 5*I*R3/ (R1+R3)
During broken string, Vdxm2 about=R2*I*R3/ (R1+R3) (maximum less than Vcc)
During short circuit, Vdxm0 about=0
Broken string threshold value=between less than Vdxm1 more than Vdxm2, it may be assumed that Vdxm2 <broken string threshold value < Vdxm1；
Short-circuit threshold value=between less than Vdxm2 more than 0, it may be assumed that 0 < short-circuit threshold value < Vdxm2.
Its threshold value ＞ short-circuit threshold value that breaks.
2, the resistance of various earphones/headset loudspeaker is substituted into above-mentioned formula respectively, choose and meet various ear simultaneously
The broken string threshold value of machine/headset loudspeaker and short-circuit threshold value；Its interrupt line threshold value need to be less than various earphones/headset loudspeaker
Magnitude of voltage during broken string；Short-circuit threshold value need to be slightly larger than zero.
Generally the resistance of earphone/headset loudspeaker is 8 Ω.
R 5 is 8 Ω, R2=1k Ω, during I=20mA, Vcc=3V, R1=100k Ω, R3=100k Ω:
Time normal, Vdxm1 about=R 5*I*R3/ (R1+R3)
=8*0.02*0.5=80mV=V1
During broken string, Vdxm2 about=R2*I*R3/ (R1+R3) (R2*I maximum be less than Vcc)
=Vcc*0.5=1.5V=V2
During short circuit, Vdxm0 about=0
Resistance in view of special headphones/headset loudspeaker is 100 Ω,
R 5 is 100 Ω, R2=1k Ω, during I=20mA, Vcc=3V, R1=100k Ω, R3=100k Ω:
Time normal, Vdxm1 about=R 5*I*R3/ (R1+R3)
=100*0.02*0.5=1V=V3
During broken string, Vdxm2 about=R2*I*R3/ (R1+R3) (R2*I maximum be less than Vcc)
=Vcc*0.5=1.5V=V4
During short circuit, Vdxm0 about=0
At this moment broken string threshold value setting=1.2V；I.e. set broken string threshold value < V2 and broken string threshold value < V4.
Short-circuit threshold value setting=50mV；That is: 0 < short-circuit threshold value < V3.
Magnitude of voltage detected during earphone/headset loudspeaker broken string > 1.2V, detect time normal that magnitude of voltage exists > 50mV with
<between 1.2V, during short circuit, magnitude of voltage < 50mV detected.
As shown in Figure 3,4, if DXm magnitude of voltage is more than broken string threshold value, then break line treatment is carried out；If DXm is electric
Pressure value is less than short-circuit threshold value, then carry out short circuit process；Otherwise broken string/short-circuit detecting terminates, for normally.
Wherein, break line treatment is particularly as follows: by sound light alarming circuit, provide break alarm.
Short circuit processes particularly as follows: by sound light alarming circuit, provide short-circuit alarming.
It addition, this utility model also includes the sound light alarming circuit being connected with MCU, when DXm magnitude of voltage > broken string
Threshold value carries out the sound and light alarm broken；When DXm magnitude of voltage, < short-circuit threshold value carries out the sound and light alarm of short circuit.
Claims (7)
1. one kind is broken and short-circuit detecting circuit towards earphone/headset loudspeaker, it is characterised in that includes MCU, measure letter
Number bleeder circuit and high-frequency signal amplify protection circuit；The detection control signal outfan of described MCU and high frequency
Signal amplifies protection circuit and connects, and the voltage signal inputs of MCU is believed with high frequency by measuring signal bleeder circuit
Number amplify protection circuit connect；Described high-frequency signal amplifies protection circuit and is located at earphone/headset loudspeaker and audio frequency letter
Between number output circuit.
One the most according to claim 1 is towards earphone/headset loudspeaker broken string and short-circuit detecting circuit, and it is special
Levy and be that described measurement signal bleeder circuit includes that the detection control signal outfan of two divider resistance: MCU leads to
Cross divider resistance R1 to be connected, also by divider resistance R3 ground connection with high-frequency signal amplification protection circuit.
One the most according to claim 1 is towards earphone/headset loudspeaker broken string and short-circuit detecting circuit, its feature
It is that described high-frequency signal amplifies protection circuit and includes divider resistance R2, electric capacity C1 and amplifier；Audio signal
The outfan of output circuit passes sequentially through amplifier, electric capacity C1 is connected with earphone/headset loudspeaker input, ear
Machine/headset loudspeaker input passes through divider resistance R2 ground connection.
4. according to the one described in any one of claims 1 to 3 towards earphone/headset loudspeaker broken string and short-circuit detecting electricity
Road, it is characterised in that: when for DC detecting, the detection control signal outfan of MCU passes sequentially through three poles
After pipe Tr1, resistance R4, then with divider resistance R2 and the Node connectedness of electric capacity C1, also with divider resistance R1
Connect；The detection control signal outfan of described MCU is connected with audion Tr1 base stage, audion Tr1's
Emitter stage is connected with power supply, and colelctor electrode is connected with resistance R4.
One the most according to claim 1 is towards earphone/headset loudspeaker broken string and short-circuit detecting circuit, its feature
Being: when being used for exchanging detection, the detection control signal outfan of MCU is by electric capacity C2 and amplifier
Input connects.
One the most according to claim 5 is towards earphone/headset loudspeaker broken string and short-circuit detecting circuit, its feature
It is: when being used for exchanging detection, measures and be connected with between the voltage signal inputs of signal bleeder circuit and MCU
Protection circuit；Described protection circuit is diode D1, D2 of two series connection；Divider resistance R1 and divider resistance
The node of R3 is connected with negative pole, the positive pole of diode D2 of diode D1, the negative pole of diode D2 and power supply
Connect, the plus earth of diode D1.
One the most according to claim 6 is towards earphone/headset loudspeaker broken string and short-circuit detecting circuit, its feature
It is: when being used for exchanging detection, between the voltage signal inputs of protection circuit and MCU, is connected with halfwave rectifier
Circuit；Described half-wave rectifying circuit includes diode D3, resistance R4 and electric capacity C3；Between diode D1, D2
Node be connected with diode D3 positive pole, diode D3 negative pole is connected with the voltage signal inputs of MCU,
The most respectively by resistance R4, electric capacity C3 ground connection.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620490503.6U CN205793346U (en) | 2016-05-26 | 2016-05-26 | A kind of towards earphone/headset loudspeaker broken string and short-circuit detecting circuit |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201620490503.6U CN205793346U (en) | 2016-05-26 | 2016-05-26 | A kind of towards earphone/headset loudspeaker broken string and short-circuit detecting circuit |
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| Publication Number | Publication Date |
|---|---|
| CN205793346U true CN205793346U (en) | 2016-12-07 |
Family
ID=58111231
Family Applications (1)
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| CN201620490503.6U Active CN205793346U (en) | 2016-05-26 | 2016-05-26 | A kind of towards earphone/headset loudspeaker broken string and short-circuit detecting circuit |
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Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107371117A (en) * | 2017-08-29 | 2017-11-21 | 广东虹勤通讯技术有限公司 | A kind of loudspeaker detection means and method |
| CN109150637A (en) * | 2018-10-31 | 2019-01-04 | 上海剑桥科技股份有限公司 | Early warning failure system and the network equipment with early warning failure function |
| CN112770244A (en) * | 2020-12-22 | 2021-05-07 | 北京城建智控科技有限公司 | Method and device for detecting line fault of loudspeaker and audio playing equipment |
-
2016
- 2016-05-26 CN CN201620490503.6U patent/CN205793346U/en active Active
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107371117A (en) * | 2017-08-29 | 2017-11-21 | 广东虹勤通讯技术有限公司 | A kind of loudspeaker detection means and method |
| CN109150637A (en) * | 2018-10-31 | 2019-01-04 | 上海剑桥科技股份有限公司 | Early warning failure system and the network equipment with early warning failure function |
| CN112770244A (en) * | 2020-12-22 | 2021-05-07 | 北京城建智控科技有限公司 | Method and device for detecting line fault of loudspeaker and audio playing equipment |
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