CN104640015A - Wireless teaching microphone circuit with MP3 (moving picture experts group audio layer-3) player - Google Patents
Wireless teaching microphone circuit with MP3 (moving picture experts group audio layer-3) player Download PDFInfo
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- CN104640015A CN104640015A CN201310561700.3A CN201310561700A CN104640015A CN 104640015 A CN104640015 A CN 104640015A CN 201310561700 A CN201310561700 A CN 201310561700A CN 104640015 A CN104640015 A CN 104640015A
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Abstract
The invention provides a wireless teaching microphone circuit with an MP3 (moving picture experts group audio layer-3) player. The wireless teaching microphone circuit comprises a speech receiving circuit, an amplifying circuit, a reverberation circuit, an audio power amplifying circuit and an MP3 circuit. An output end of the speech receiving circuit and an output end of the MP3 circuit are respectively connected with input ends of the amplifying circuit; an output end of the amplifying circuit is connected with an input end of the reverberation circuit and an input end of the audio power amplifying circuit; an output end of the reverberation circuit is further connected with an input end of the audio power amplifying circuit. The wireless teaching microphone circuit with the MP3 player has the advantages that the wireless teaching microphone circuit has an MP3 playing function and wireless microphone functions, the same audio power amplifying circuit is shared by the MP3 playing function and the wireless microphone functions, accordingly, audio power amplifying chips and large quantities of relevant components such as resistors and capacitors can be omitted, and the manufacturing cost can be saved while functions are increased.
Description
Technical field
The present invention relates to MP3 player, be specifically related to the MP3 player of wireless teaching microphone system.
Background technology
Traditional wireless teaching microphone system, comprises host machine part and wireless microphone radiating portion, receives transmitting of wireless microphone, process and broadcasting of raising one's voice to signal by host machine part.But traditional wireless teaching microphone system does not have MP3 playing function, needing to carry out MP3 broadcasting is also need extra MP3 equipment, or the power amplifier that extra increase is new in existing equipment, increases equipment cost.
Summary of the invention
Not enough for above-mentioned prior art, the technical problem to be solved in the present invention is to provide a kind of wireless teaching microphone circuit with MP3 player, makes wireless teaching microphone system can have MP3 playing function and microphone loud-speaking function simultaneously, and reduces costs.
For solving the problems of the technologies described above, the technical solution used in the present invention is, the wireless teaching microphone circuit of band MP3 player, comprises phonetic incepting circuit, amplifying circuit, reverberation circuit and audio power amplifier circuit; Also comprise MP3 circuit; The output of phonetic incepting circuit is connected with the input of amplifying circuit respectively with the output of MP3 circuit; The output of amplifying circuit is connected with the input of reverberation circuit, the input of audio power amplifier circuit respectively; The output of reverberation circuit is also connected with the input of audio power amplifier circuit.Such structure can make MP3 circuit and phonetic incepting circuit share same audio power amplifier circuit, saves components and parts cost, and realizes MP3 playing function and microphone function simultaneously.
Particularly, described MP3 circuit comprises MP3 chip, and the control inputs pin of MP3 chip is connected with a key circuit, and the power end of MP3 chip is connected to direct current 5V source of stable pressure; The ground end ground connection of MP3 chip; The output of MP3 chip is the output of MP3 circuit, is connected with the input of amplifying circuit.
Further technical scheme is, also comprises wired microphone input circuit; The input of this wire microphone input circuit is the audio interface for grafting microphone, and the output of wire microphone input circuit is connected with the output of MP3 circuit.Such structure makes the present invention have the function of wire microphone simultaneously, and shares same audio power amplifier circuit, increases function further and saves components and parts cost.
Particularly, the anode of the audio interface of described wire microphone input circuit is connected with the negative electrode of electrochemical capacitor C5, the reference edge ground connection of audio interface; The anode of electrochemical capacitor C5 is by resistance R14 ground connection, and the anode of electrochemical capacitor C5 is also connected with the base stage of NPN triode Q3 by resistance R3; The emitter of NPN triode Q3 is by resistance R36 ground connection, and the collector electrode of NPN triode Q3 is connected with the base stage of NPN triode Q3 by resistance R33; The collector electrode of NPN triode Q3 is also connected to the first end of potentiometer R9 by the series arm of resistance R13 and electric capacity C2, the second end ground connection of potentiometer R9, and the contact of potentiometer R9 is the output of wire microphone input circuit; The collector electrode of NPN triode Q3 is also connected with the first end of resistance R2, and second end of resistance R2 is by electrochemical capacitor C4 ground connection, and second end of resistance R2 is also connected to direct current 5V source of stable pressure by resistance R12.Such structure ensures that wired microphone input circuit can share same audio power amplifier circuit with MP3 circuit further.
Particularly, described phonetic incepting circuit is also connected with indicator light circuit; The voice output of phonetic incepting circuit is by potentiometer R10 ground connection, and the contact of potentiometer R10 is the output of phonetic incepting circuit; Described phonetic incepting circuit has reference edge, and described MP3 circuit also has reference edge, and the reference edge of phonetic incepting circuit is connected with the reference edge of MP3 circuit.Such structure strengthens the anti-static ability between phonetic incepting circuit and MP3 circuit, improves anti-jamming effectiveness, ensures sharing audio power amplifier circuit further.
Particularly, described amplifying circuit comprises amplifier IC3 and amplifier IC4; The output of MP3 circuit is by resistance R29 ground connection, and the output of MP3 circuit is also connected to the negative input end of amplifier IC3 by the series arm of electric capacity C16 and resistance R30; The output of amplifier IC3 is connected with the negative input end of amplifier IC3 with the parallel branch of electric capacity C39 by resistance R35; The output of amplifier IC3 is connected to the negative electrode of electrochemical capacitor C14 by the series arm of electric capacity C17 and resistance R31, the two ends of resistance R31 are also parallel with electric capacity C35; The anode of electrochemical capacitor C14 is connected to the negative input end of amplifier IC4; The output of phonetic incepting circuit is connected to the negative electrode of electrochemical capacitor C14 by the parallel branch of electric capacity C33 and resistance R22; The output of amplifier IC4 is connected with the negative input end of amplifier IC4 with the parallel branch of resistance R34 by electric capacity C38; The positive input terminal of amplifier IC4 is connected with the positive input terminal of amplifier IC3, and the positive input terminal of amplifier IC4 is also by the parallel branch ground connection of electric capacity C18 and resistance R32; The output of amplifier IC4 is connected to the first end of resistance R26 by the series arm of electric capacity C15 and resistance R59, second end of resistance R26 is by electric capacity C34 ground connection; The first end of resistance R26 is also connected with the first end of electric capacity C29, and second end of electric capacity C29 is connected with second end of resistance R26 by potentiometer R58; Second end of electric capacity C29 is also connected to the contact of potentiometer R58 by resistance R23; The first end of electric capacity C29 is also connected to the contact of potentiometer R58 by resistance R25; Second end of resistance R26 is also connected to the contact of potentiometer R58 by resistance R57; The contact of resistance R58 is the output of amplifying circuit.
Particularly, described reverberation circuit comprises CD2399 chip; First pin of CD2399 chip is connected with direct current 5V source of stable pressure; Second pin of CD2399 chip is by electrochemical capacitor C42 ground connection; Three-prong and the 4th pin of CD2399 chip link together and ground connection; 6th pin of CD2399 chip is by potentiometer R60 ground connection, and the contact of potentiometer R60 is connected to the 6th pin of CD2399 chip; 7th pin of CD2399 chip is by electric capacity C44 ground connection; 8th pin electric capacity C46 ground connection of CD2399 chip; 9th pin of CD2399 chip is connected to the tenth pin of CD2399 chip by electric capacity C45; 11 pin of CD2399 chip is connected to the 12 pin of CD2399 chip by electric capacity C43, the 12 pin of CD2399 chip is also connected to the first end of electric capacity C21 by resistance R18, the second end ground connection of electric capacity C21; Tenth three-prong of CD2399 chip is connected to the first end of electric capacity C21 by resistance R17, the tenth three-prong of CD2399 chip is also connected to the 14 pin of CD2399 chip by electric capacity C41; 14 pin of CD2399 chip is also connected with the first end of electric capacity C21 by resistance R51; 15 pin of CD2399 chip is connected with the 16 pin of CD2399 chip by electric capacity C40,15 pin of CD2399 chip is also connected to the anode of electrochemical capacitor C3 by resistance R27,16 pin of CD2399 chip is also connected to the anode of electrochemical capacitor C3 by resistance R28, the negative electrode of electrochemical capacitor C3 be reverberation circuit input and by electric capacity C37 ground connection; 14 pin of CD2399 chip is also connected to the first end of electric capacity C22 by electric capacity R56, the second end ground connection of electric capacity C22, the first end of electric capacity C22 is also connected to the anode of electrochemical capacitor C6, the negative electrode of electrochemical capacitor C6 is connected to the first end of potentiometer R11 by resistance R19, the second end ground connection of potentiometer R11, the contact of potentiometer R11 is connected to the negative electrode of electrochemical capacitor C6; The first end of potentiometer R11 is the output of reverberation circuit and is connected to the negative electrode of electrochemical capacitor C3 by resistance R50.
Particularly, described audio power amplifier circuit comprises TDA2004 chip; First pin of TDA2004 chip is connected to the anode of electrochemical capacitor C13, the minus earth of electrochemical capacitor C13; Second pin of TDA2004 chip is connected to the anode of electrochemical capacitor C9, the negative electrode of electrochemical capacitor C9 is connected to the negative electrode of electrochemical capacitor C8 by resistance R45, the negative electrode of electrochemical capacitor C8 is also by resistance R44 ground connection, and the anode of electrochemical capacitor C8 is connected to the 4th pin of TDA2004 chip; The three-prong of TDA2004 chip is connected to the anode of electrochemical capacitor C10, the minus earth of electrochemical capacitor C10, and the three-prong of TDA2004 chip is also connected to power supply VCC+ by resistance R46; 6th pin ground connection of TDA2004 chip; 8th pin of TDA2004 chip is connected to the negative electrode of electrochemical capacitor C8 by resistance R39, the 8th pin of TDA2004 chip is also by the series arm ground connection of resistance R7, electric capacity C20; 9th pin of TDA2004 chip is connected to power supply VCC+; Tenth pin of TDA2004 chip is connected to the negative electrode of electrochemical capacitor C9 by resistance R24; 11 pin of TDA2004 chip is connected with the anode of electrochemical capacitor C12, and the negative electrode of electrochemical capacitor C12 is connected to the tenth pin of TDA2004 chip; Power supply VCC+ is also connected to the anode of electrochemical capacitor C11, the minus earth of electrochemical capacitor C11; 5th pin of TDA2004 chip is connected to the anode of electrochemical capacitor C19, and the negative electrode of electrochemical capacitor C19 is the input of audio power amplifier circuit; 8th pin of TDA2004 chip and the tenth pin are respectively as the anode of audio power amplifier circuit output and negative terminal.
Further, also reference voltage circuit is comprised; Described reference voltage circuit comprises direct current input interface; Direct current input interface is connected to the first end of resistance R8 by diode D11, second end of resistance R8 is connected to the input of 8V pressurizer Q10, the reference edge ground connection of 8V pressurizer Q10, the output of 8V pressurizer Q10 passes through the parallel branch ground connection of electrochemical capacitor C27 and electric capacity C28; The output of 8V pressurizer Q10 is also connected to the collector electrode of NPN triode Q5, the collector electrode of NPN triode Q5 is also connected to the base stage of NPN triode Q5 by resistance R15, the collector electrode of NPN triode Q5 is connected to the base stage of NPN triode Q6 by resistance R43, the base stage of NPN triode Q6 is by electrochemical capacitor C30 ground connection, the grounded emitter of NPN triode Q6, the collector electrode of NPN triode Q6 is also connected to the base stage of NPN triode Q5; The collector electrode of NPN triode Q5 is connected to the base stage of PNP triode Q11 by resistance R16, the collector electrode of NPN triode Q5 is connected to the emitter of PNP triode Q11 by diode D5, the emitter of NPN triode Q5 is connected to the collector electrode of PNP triode, the emitter of PNP triode Q11 is also by electrochemical capacitor C7 ground connection, and the collector electrode of PNP triode Q11 is also by electrochemical capacitor C31 ground connection; The collector electrode of PNP triode Q11 is connected to the base stage of NPN triode Q7 by resistance R40, the grounded emitter of NPN triode Q7, and the collector electrode of NPN triode Q7 passes through the parallel branch ground connection of electric capacity C36, resistance R55; The current collection of NPN triode Q7 very reference voltage circuit output and be connected with the input of audio power amplifier circuit.
Again further, described diode D11 is connected with the first end of resistance R8 by selector switch S5, the negative electrode of diode D11 is connected with the common port of selector switch S5, the first end of selector switch S5 is connected with the first end of resistance R8, second end of selector switch S5 is connected with the first anode of bidirectional thyristor Q8, and the second plate of bidirectional thyristor Q8 is connected to second end of selector switch S5 by resistance R37; Second end of selector switch S5 is also connected to the positive power source terminal of amplifier AR1 and the positive power source terminal of amplifier AR2, the negative power end of amplifier AR1 and the equal ground connection of the negative power end of amplifier AR2; Second end of selector switch S5 is also connected with the positive input terminal of amplifier AR1 by resistance R52; The positive input terminal of amplifier AR1 is also connected with the anode of thyristor Q9, the negative electrode of thyristor Q9 is connected to the positive input terminal of amplifier AR1 by resistance R54, the negative electrode of thyristor Q9 is also by resistance R21 ground connection, the control pole ground connection of thyristor Q9, the negative input end of amplifier AR1 is connected to the anode of 12VDC interface J7 by resistance R48; The control pole of bidirectional thyristor Q8 is also connected to the output of amplifier AR1 by resistance R20; The anode of 12VDC interface J7 is also connected to the positive input terminal of amplifier AR2 by resistance R49, the negative input end of amplifier AR2 is connected to the anode of light-emitting diode D13 by resistance R61, the minus earth of light-emitting diode D13, the output of amplifier AR2 is connected to the output of amplifier AR1 by resistance R47; The negativing ending grounding of 12VDC interface J7; The first end of selector switch S5 is also connected to the common port of selector switch S5 by the series arm of resistance R53, diode D9, diode D12; The 0V pin of power supply wire jumper interface J6 is connected with the common port of selector switch S5 with the parallel branch of electric capacity C25 by diode D7, electric capacity C24, diode D8, wherein the anode of diode D7, the anode of diode D8 are connected with the 0V pin of power supply wire jumper interface J6, the 0V pin of power supply wire jumper interface J6 is also by the parallel branch ground connection of electric capacity C23 and diode D6, and wherein the negative electrode of diode D6 is connected with the 0V pin of power supply wire jumper interface J6; The common port of selector switch S5 is also connected to the anode of electrochemical capacitor C26, the minus earth of electrochemical capacitor C26.
The wireless teaching microphone circuit of band MP3 player of the present invention is while having MP3 playing function and radio microphone function concurrently, realize MP3 function and the shared audio power amplifier circuit of radio microphone function, save audio frequency power amplifier chip and a large amount of relevant components and parts such as resistance, electric capacity, increase function and save cost of manufacture simultaneously.
Accompanying drawing explanation
In order to be illustrated more clearly in the embodiment of the present invention or technical scheme of the prior art, be briefly described to the accompanying drawing used required in embodiment or description of the prior art below, apparently, accompanying drawing in the following describes is only some embodiments of the present invention, for those of ordinary skill in the art, under the prerequisite not paying creative work, other accompanying drawing can also be obtained according to these accompanying drawings.
Fig. 1 is the structural representation of the wireless teaching microphone circuit of band MP3 player of the present invention.
Fig. 2 is the MP3 circuit of wireless teaching microphone circuit and the structural representation of wire microphone input circuit of band MP3 player of the present invention.
Fig. 3 is the amplification circuit structure schematic diagram of the wireless teaching microphone circuit of band MP3 player of the present invention.
Fig. 4 is the reverberation circuit structural representation of the wireless teaching microphone circuit of band MP3 player of the present invention.
Fig. 5 is the audio power amplifier circuit of the wireless teaching microphone circuit of band MP3 player of the present invention.
Fig. 6 is the reference voltage circuit of the wireless teaching microphone circuit of band MP3 player of the present invention.
Embodiment
Below in conjunction with the drawings and specific embodiments, the present invention is described in further detail.
As shown in Figure 1, the wireless teaching microphone circuit of band MP3 player of the present invention, comprises phonetic incepting circuit 1, amplifying circuit 4, reverberation circuit 6 and audio power amplifier circuit 5; Also comprise MP3 circuit 2; The output of phonetic incepting circuit 1 is connected with the input of amplifying circuit 4 respectively with the output of MP3 circuit 2; The output 101 of amplifying circuit 4 is connected with the input 302 of reverberation circuit 6, the input 202 of audio power amplifier circuit 5 respectively; The output 301 of reverberation circuit 6 is also connected with the input 202 of audio power amplifier circuit 5.
Wherein, as shown in Figure 2, described MP3 circuit 2 comprises MP3 chip, and the control inputs pin of MP3 chip is connected with a key circuit, and the 5th pin of MP3 chip is connected to the first pin by button S4, as STOP button particularly; 4th pin of MP3 chip is connected to the first pin by button S3, as PREV button; The three-prong of MP3 chip by being connected to the first pin by pin S2, as NEXT button; Second pin of MP3 chip is connected to the first pin by button S1, as PLAY button; The power end of MP3 chip, i.e. the tenth pin, be connected to direct current 5V source of stable pressure; The ground end of MP3 chip, i.e. the 8th pin, ground connection; The output of MP3 chip, i.e. the 16 pin, for the output of whole MP3 circuit 2, be connected with the input of amplifying circuit 4, in the present embodiment, the output of MP3 chip is connected with amplifying circuit 4 by wire jumper interface J3, and one end of wire jumper interface J3 is connected with the output of MP3 chip, the other end ground connection of wire jumper interface J3.Interface J2 be MP3 chip carry interface.Also comprise wired microphone input circuit 3; The input of this wire microphone input circuit 3 is the audio interface for grafting microphone, and the output of wire microphone input circuit 3 is connected with the output of MP3 circuit 2.Particularly, the anode of the audio interface of described wire microphone input circuit 3 is connected with the negative electrode of electrochemical capacitor C5, the reference edge ground connection of audio interface; The anode of electrochemical capacitor C5 is by resistance R14 ground connection, and the anode of electrochemical capacitor C5 is also connected with the base stage of NPN triode Q3 by resistance R3; The emitter of NPN triode Q3 is by resistance R36 ground connection, and the collector electrode of NPN triode Q3 is connected with the base stage of NPN triode Q3 by resistance R33; The collector electrode of NPN triode Q3 is also connected to the first end of potentiometer R9 by the series arm of resistance R13 and electric capacity C2, the second end ground connection of potentiometer R9, and the contact of potentiometer R9 is the output of wire microphone input circuit 3; The collector electrode of NPN triode Q3 is also connected with the first end of resistance R2, and second end of resistance R2 is by electrochemical capacitor C4 ground connection, and second end of resistance R2 is also connected to direct current 5V source of stable pressure by resistance R12.Direct current 5V source of stable pressure is realized by three terminal regulator Q1, in the present embodiment, three terminal regulator Q1 adopts 78L05 model, the input termination DC power supply of three terminal regulator Q1, hold ground connection, output by electrochemical capacitor C1 ground connection, the output of three terminal regulator Q1 is direct current 5V source of stable pressure.Described phonetic incepting circuit 1 is also connected with indicator light circuit, and the wire jumper interface J1 be connected with phonetic incepting circuit 1 is only shown in Fig. 2, and first pin of wire jumper interface J1 is connected with the anode of light-emitting diode D1, the minus earth of light-emitting diode D1; Second pin of wire jumper interface J1 is 8V power supply, is connected with the input of three terminal regulator Q1 by resistance R36; 3rd pin of wire jumper interface J1 is power supply VCC+, by the series arm ground connection of resistance R1 and light-emitting diode D2,3rd pin of wire jumper interface J1 is also connected with the first end of resistance R41, second end of resistance R41 is by light-emitting diode D3 ground connection, second end of resistance R41 is also connected with the collector electrode of NPN triode Q4, the grounded emitter of NPN triode Q4, the base stage of NPN triode Q4 is connected with the anode of voltage stabilizing didoe D4, and the negative electrode of voltage stabilizing didoe D4 is connected with the 3rd pin of wire jumper interface J1; 4th pin of wire jumper interface J1 is the voice output of phonetic incepting circuit 1, and by potentiometer R10 ground connection, the contact of potentiometer R10 is the output of phonetic incepting circuit 1, and is connected with amplifying circuit 4 by the 5th pin of wire jumper interface J1; Phonetic incepting circuit 1 has reference edge, and the 6th pin of wire jumper interface J1 is connected to the reference edge of phonetic incepting circuit 1, and described MP3 circuit 2 also has reference edge, and the reference edge of MP3 circuit 2 is the 11 pin of MP3 chip; Described reference edge is identical with the electromotive force of ground connection, but not directly be connected, be equivalent to second " ground connection ", such mode can effectively antistatic be anti-interference; The reference edge of phonetic incepting circuit 1 is connected with the reference edge of MP3 circuit 2.
As shown in Figure 3, described amplifying circuit 4 comprises amplifier IC3 and amplifier IC4, the IC chip adopting double operational to become one in the present embodiment, and two amplifiers have identical power end and earth terminal on IC chip pin; Wire jumper interface J3 is connected with wire jumper interface J8, the first end of wire jumper interface J8, the i.e. output of MP3 circuit 2, by resistance R29 ground connection, the second end also ground connection of wire jumper interface J8, the output of MP3 circuit 2 is also connected to the negative input end of amplifier IC3 by the series arm of electric capacity C16 and resistance R30; The output of amplifier IC3 is connected with the negative input end of amplifier IC3 with the parallel branch of electric capacity C39 by resistance R35; The output of amplifier IC3 is connected to the negative electrode of electrochemical capacitor C14 by the series arm of electric capacity C17 and resistance R31, the two ends of resistance R31 are also parallel with electric capacity C35; The anode of electrochemical capacitor C14 is connected to the negative input end of amplifier IC4; The output of phonetic incepting circuit 1 is connected to the negative electrode of electrochemical capacitor C14 by the parallel branch of electric capacity C33 and resistance R22; The output of amplifier IC4 is connected with the negative input end of amplifier IC4 with the parallel branch of resistance R34 by electric capacity C38; The positive input terminal of amplifier IC4 is connected with the positive input terminal of amplifier IC3, and the positive input terminal of amplifier IC4 is also by the parallel branch ground connection of electric capacity C18 and resistance R32; The output of amplifier IC4 is connected to the first end of resistance R26 by the series arm of electric capacity C15 and resistance R59, second end of resistance R26 is by electric capacity C34 ground connection; The first end of resistance R26 is also connected with the first end of electric capacity C29, and second end of electric capacity C29 is connected with second end of resistance R26 by potentiometer R58; Second end of electric capacity C29 is also connected to the contact of potentiometer R58 by resistance R23; The first end of electric capacity C29 is also connected to the contact of potentiometer R58 by resistance R25; Second end of resistance R26 is also connected to the contact of potentiometer R58 by resistance R57; The contact of resistance R58 is the output 101 of amplifying circuit 4, and in the present embodiment, the output 101 of amplifying circuit 4 is also schemed not shown by resistance R5() be connected with the input 202 of audio power amplifier circuit 5.
As shown in Figure 4, described reverberation circuit 6 comprises CD2399 chip; First pin of CD2399 chip is connected with direct current 5V source of stable pressure; Second pin of CD2399 chip is by electrochemical capacitor C42 ground connection; Three-prong and the 4th pin of CD2399 chip link together and ground connection; 6th pin of CD2399 chip is by potentiometer R60 ground connection, and the contact of potentiometer R60 is connected to the 6th pin of CD2399 chip; 7th pin of CD2399 chip is by electric capacity C44 ground connection; 8th pin electric capacity C46 ground connection of CD2399 chip; 9th pin of CD2399 chip is connected to the tenth pin of CD2399 chip by electric capacity C45; 11 pin of CD2399 chip is connected to the 12 pin of CD2399 chip by electric capacity C43, the 12 pin of CD2399 chip is also connected to the first end of electric capacity C21 by resistance R18, the second end ground connection of electric capacity C21; Tenth three-prong of CD2399 chip is connected to the first end of electric capacity C21 by resistance R17, the tenth three-prong of CD2399 chip is also connected to the 14 pin of CD2399 chip by electric capacity C41; 14 pin of CD2399 chip is also connected with the first end of electric capacity C21 by resistance R51; 15 pin of CD2399 chip is connected with the 16 pin of CD2399 chip by electric capacity C40,15 pin of CD2399 chip is also connected to the anode of electrochemical capacitor C3 by resistance R27,16 pin of CD2399 chip is also connected to the anode of electrochemical capacitor C3 by resistance R28, the negative electrode of electrochemical capacitor C3 is by electric capacity C37 ground connection, the negative electrode of electrochemical capacitor C3 is the input 302 of reverberation circuit 6, and in the present embodiment, the input 302 of reverberation circuit 6 is also schemed not shown by resistance R24() be connected with the output 101 of amplifying circuit 4; 14 pin of CD2399 chip is also connected to the first end of electric capacity C22 by electric capacity R56, the second end ground connection of electric capacity C22, the first end of electric capacity C22 is also connected to the anode of electrochemical capacitor C6, the negative electrode of electrochemical capacitor C6 is connected to the first end of potentiometer R11 by resistance R19, the second end ground connection of potentiometer R11, the contact of potentiometer R11 is connected to the negative electrode of electrochemical capacitor C6; The first end of potentiometer R11 is connected to the negative electrode of electrochemical capacitor C3 by resistance R50; The first end of potentiometer R11 is the output 301 of reverberation circuit 6, and in the present embodiment, the output 301 of reverberation circuit 6 is also schemed not shown by resistance R42() be connected to the input 202 of audio power amplifier circuit 5.
As shown in Figure 5, described audio power amplifier circuit 5 comprises TDA2004 chip; First pin of TDA2004 chip is connected to the anode of electrochemical capacitor C13, the minus earth of electrochemical capacitor C13; Second pin of TDA2004 chip is connected to the anode of electrochemical capacitor C9, the negative electrode of electrochemical capacitor C9 is connected to the negative electrode of electrochemical capacitor C8 by resistance R45, the negative electrode of electrochemical capacitor C8 is also by resistance R44 ground connection, and the anode of electrochemical capacitor C8 is connected to the 4th pin of TDA2004 chip; The three-prong of TDA2004 chip is connected to the anode of electrochemical capacitor C10, the minus earth of electrochemical capacitor C10, and the three-prong of TDA2004 chip is also connected to power supply VCC+ by resistance R46; 6th pin ground connection of TDA2004 chip; 8th pin of TDA2004 chip is connected to the negative electrode of electrochemical capacitor C8 by resistance R39, the 8th pin of TDA2004 chip is also by the series arm ground connection of resistance R7, electric capacity C20; 9th pin of TDA2004 chip is connected to power supply VCC+; Tenth pin of TDA2004 chip is connected to the negative electrode of electrochemical capacitor C9 by resistance R24; 11 pin of TDA2004 chip is connected with the anode of electrochemical capacitor C12, and the negative electrode of electrochemical capacitor C12 is connected to the tenth pin of TDA2004 chip; Power supply VCC+ is also connected to the anode of electrochemical capacitor C11, the minus earth of electrochemical capacitor C11; 5th pin of TDA2004 chip is connected to the anode of electrochemical capacitor C19, and the negative electrode of electrochemical capacitor C19 is the input 202 of audio power amplifier circuit 5; 8th pin of TDA2004 chip and the tenth pin are respectively as the anode of audio power amplifier circuit 5 output and negative terminal, and the anode of the present embodiment sound intermediate frequency power amplifier 5 output is connected with phonation circuits such as loud speakers by wire jumper interface J5 with negative terminal.
As shown in Figure 6, the present invention also comprises reference voltage circuit 7; Described reference voltage circuit 7 comprises direct current input interface; Direct current input interface is connected to the first end of resistance R8 by diode D11, second end of resistance R8 is connected to the input of 8V pressurizer Q10, the reference edge ground connection of 8V pressurizer Q10, the output of 8V pressurizer Q10 passes through the parallel branch ground connection of electrochemical capacitor C27 and electric capacity C28; The output of 8V pressurizer Q10 is also connected to the collector electrode of NPN triode Q5, the collector electrode of NPN triode Q5 is also connected to the base stage of NPN triode Q5 by resistance R15, the collector electrode of NPN triode Q5 is connected to the base stage of NPN triode Q6 by resistance R43, the base stage of NPN triode Q6 is by electrochemical capacitor C30 ground connection, the grounded emitter of NPN triode Q6, the collector electrode of NPN triode Q6 is also connected to the base stage of NPN triode Q5; The collector electrode of NPN triode Q5 is connected to the base stage of PNP triode Q11 by resistance R16, the collector electrode of NPN triode Q5 is connected to the emitter of PNP triode Q11 by diode D5, the emitter of NPN triode Q5 is connected to the collector electrode of PNP triode, the emitter of PNP triode Q11 is also by electrochemical capacitor C7 ground connection, and the collector electrode of PNP triode Q11 is also by electrochemical capacitor C31 ground connection; The collector electrode of PNP triode Q11 is connected to the base stage of NPN triode Q7 by resistance R40, the grounded emitter of NPN triode Q7, and the collector electrode of NPN triode Q7 passes through the parallel branch ground connection of electric capacity C36, resistance R55; The current collection of NPN triode Q7 very reference voltage circuit 7 output 401 and be connected with the input 202 of audio power amplifier circuit 5.Described diode D11 is connected with the first end of resistance R8 by selector switch S5, the negative electrode of diode D11 is connected with the common port of selector switch S5, the first end of selector switch S5 is connected with the first end of resistance R8, second end of selector switch S5 is connected with the first anode of bidirectional thyristor Q8, and the second plate of bidirectional thyristor Q8 is connected to second end of selector switch S5 by resistance R37; Second end of selector switch S5 is also connected to the positive power source terminal of amplifier AR1 and the positive power source terminal of amplifier AR2, the negative power end of amplifier AR1 and the equal ground connection of the negative power end of amplifier AR2, adopt the IC chip of double operational in the present embodiment, amplifier AR1 and amplifier AR2 has identical positive power source terminal and negative power end; Second end of selector switch S5 is also connected with the positive input terminal of amplifier AR1 by resistance R52; The positive input terminal of amplifier AR1 is also connected with the anode of thyristor Q9, the negative electrode of thyristor Q9 is connected to the positive input terminal of amplifier AR1 by resistance R54, the negative electrode of thyristor Q9 is also by resistance R21 ground connection, the control pole ground connection of thyristor Q9, the negative input end of amplifier AR1 is connected to the anode of 12VDC interface J7 by resistance R48; The control pole of bidirectional thyristor Q8 is also connected to the output of amplifier AR1 by resistance R20; The anode of 12VDC interface J7 is also connected to the positive input terminal of amplifier AR2 by resistance R49, the negative input end of amplifier AR2 is connected to the anode of light-emitting diode D13 by resistance R61, the minus earth of light-emitting diode D13, the output of amplifier AR2 is connected to the output of amplifier AR1 by resistance R47; The negativing ending grounding of 12VDC interface J7; The first end of selector switch S5 is also connected to the common port of selector switch S5 by the series arm of resistance R53, diode D9, diode D12; The 0V pin of power supply wire jumper interface J6 is connected with the common port of selector switch S5 with the parallel branch of electric capacity C25 by diode D7, electric capacity C24, diode D8, wherein the anode of diode D7, the anode of diode D8 are connected with the 0V pin of power supply wire jumper interface J6, the 0V pin of power supply wire jumper interface J6 is also by the parallel branch ground connection of electric capacity C23 and diode D6, and wherein the negative electrode of diode D6 is connected with the 0V pin of power supply wire jumper interface J6; The common port of selector switch S5 is also connected to the anode of electrochemical capacitor C26, the minus earth of electrochemical capacitor C26.This spline structure provides stable reference voltage, and has charge function simultaneously, can to inner power source charges, and described internal electric source is not included in the present invention.
The foregoing is only preferred embodiment of the present invention, not in order to limit the present invention, within the spirit and principles in the present invention all, any amendment done, equivalent replacement, improvement etc., all should be included within protection scope of the present invention.
Claims (10)
1. be with the wireless teaching microphone circuit of MP3 player, comprise phonetic incepting circuit, amplifying circuit, reverberation circuit and audio power amplifier circuit; It is characterized in that: also comprise MP3 circuit; The output of phonetic incepting circuit is connected with the input of amplifying circuit respectively with the output of MP3 circuit; The output of amplifying circuit is connected with the input of reverberation circuit, the input of audio power amplifier circuit respectively; The output of reverberation circuit is also connected with the input of audio power amplifier circuit.
2. the wireless teaching microphone circuit of band MP3 player according to claim 1, it is characterized in that: described MP3 circuit comprises MP3 chip, the control inputs pin of MP3 chip is connected with a key circuit, and the power end of MP3 chip is connected to direct current 5V source of stable pressure; The ground end ground connection of MP3 chip; The output of MP3 chip is the output of MP3 circuit, is connected with the input of amplifying circuit.
3. the wireless teaching microphone circuit of band MP3 player according to claim 1, is characterized in that: also comprise wired microphone input circuit; The input of this wire microphone input circuit is the audio interface for grafting microphone, and the output of wire microphone input circuit is connected with the output of MP3 circuit.
4. the wireless teaching microphone circuit of band MP3 player according to claim 3, is characterized in that: the anode of the audio interface of described wire microphone input circuit is connected with the negative electrode of electrochemical capacitor C5, the reference edge ground connection of audio interface; The anode of electrochemical capacitor C5 is by resistance R14 ground connection, and the anode of electrochemical capacitor C5 is also connected with the base stage of NPN triode Q3 by resistance R3; The emitter of NPN triode Q3 is by resistance R36 ground connection, and the collector electrode of NPN triode Q3 is connected with the base stage of NPN triode Q3 by resistance R33; The collector electrode of NPN triode Q3 is also connected to the first end of potentiometer R9 by the series arm of resistance R13 and electric capacity C2, the second end ground connection of potentiometer R9, and the contact of potentiometer R9 is the output of wire microphone input circuit; The collector electrode of NPN triode Q3 is also connected with the first end of resistance R2, and second end of resistance R2 is by electrochemical capacitor C4 ground connection, and second end of resistance R2 is also connected to direct current 5V source of stable pressure by resistance R12.
5. the wireless teaching microphone circuit of the band MP3 player according to claim 1-4 any one, is characterized in that: described phonetic incepting circuit is also connected with indicator light circuit; The voice output of phonetic incepting circuit is by potentiometer R10 ground connection, and the contact of potentiometer R10 is the output of phonetic incepting circuit; Described phonetic incepting circuit has reference edge, and described MP3 circuit also has reference edge, and the reference edge of phonetic incepting circuit is connected with the reference edge of MP3 circuit.
6. the wireless teaching microphone circuit of band MP3 player according to claim 5, is characterized in that: described amplifying circuit comprises amplifier IC3 and amplifier IC4; The output of MP3 circuit is by resistance R29 ground connection, and the output of MP3 circuit is also connected to the negative input end of amplifier IC3 by the series arm of electric capacity C16 and resistance R30; The output of amplifier IC3 is connected with the negative input end of amplifier IC3 with the parallel branch of electric capacity C39 by resistance R35; The output of amplifier IC3 is connected to the negative electrode of electrochemical capacitor C14 by the series arm of electric capacity C17 and resistance R31, the two ends of resistance R31 are also parallel with electric capacity C35; The anode of electrochemical capacitor C14 is connected to the negative input end of amplifier IC4; The output of phonetic incepting circuit is connected to the negative electrode of electrochemical capacitor C14 by the parallel branch of electric capacity C33 and resistance R22; The output of amplifier IC4 is connected with the negative input end of amplifier IC4 with the parallel branch of resistance R34 by electric capacity C38; The positive input terminal of amplifier IC4 is connected with the positive input terminal of amplifier IC3, and the positive input terminal of amplifier IC4 is also by the parallel branch ground connection of electric capacity C18 and resistance R32; The output of amplifier IC4 is connected to the first end of resistance R26 by the series arm of electric capacity C15 and resistance R59, second end of resistance R26 is by electric capacity C34 ground connection; The first end of resistance R26 is also connected with the first end of electric capacity C29, and second end of electric capacity C29 is connected with second end of resistance R26 by potentiometer R58; Second end of electric capacity C29 is also connected to the contact of potentiometer R58 by resistance R23; The first end of electric capacity C29 is also connected to the contact of potentiometer R58 by resistance R25; Second end of resistance R26 is also connected to the contact of potentiometer R58 by resistance R57; The contact of resistance R58 is the output of amplifying circuit.
7. the wireless teaching microphone circuit of band MP3 player according to claim 1, is characterized in that: described reverberation circuit comprises CD2399 chip; First pin of CD2399 chip is connected with direct current 5V source of stable pressure; Second pin of CD2399 chip is by electrochemical capacitor C42 ground connection; Three-prong and the 4th pin of CD2399 chip link together and ground connection; 6th pin of CD2399 chip is by potentiometer R60 ground connection, and the contact of potentiometer R60 is connected to the 6th pin of CD2399 chip; 7th pin of CD2399 chip is by electric capacity C44 ground connection; 8th pin electric capacity C46 ground connection of CD2399 chip; 9th pin of CD2399 chip is connected to the tenth pin of CD2399 chip by electric capacity C45; 11 pin of CD2399 chip is connected to the 12 pin of CD2399 chip by electric capacity C43, the 12 pin of CD2399 chip is also connected to the first end of electric capacity C21 by resistance R18, the second end ground connection of electric capacity C21; Tenth three-prong of CD2399 chip is connected to the first end of electric capacity C21 by resistance R17, the tenth three-prong of CD2399 chip is also connected to the 14 pin of CD2399 chip by electric capacity C41; 14 pin of CD2399 chip is also connected with the first end of electric capacity C21 by resistance R51; 15 pin of CD2399 chip is connected with the 16 pin of CD2399 chip by electric capacity C40,15 pin of CD2399 chip is also connected to the anode of electrochemical capacitor C3 by resistance R27,16 pin of CD2399 chip is also connected to the anode of electrochemical capacitor C3 by resistance R28, the negative electrode of electrochemical capacitor C3 be reverberation circuit input and by electric capacity C37 ground connection; 14 pin of CD2399 chip is also connected to the first end of electric capacity C22 by electric capacity R56, the second end ground connection of electric capacity C22, the first end of electric capacity C22 is also connected to the anode of electrochemical capacitor C6, the negative electrode of electrochemical capacitor C6 is connected to the first end of potentiometer R11 by resistance R19, the second end ground connection of potentiometer R11, the contact of potentiometer R11 is connected to the negative electrode of electrochemical capacitor C6; The first end of potentiometer R11 is the output of reverberation circuit and is connected to the negative electrode of electrochemical capacitor C3 by resistance R50.
8. the wireless teaching microphone circuit of band MP3 player according to claim 1, is characterized in that: described audio power amplifier circuit comprises TDA2004 chip; First pin of TDA2004 chip is connected to the anode of electrochemical capacitor C13, the minus earth of electrochemical capacitor C13; Second pin of TDA2004 chip is connected to the anode of electrochemical capacitor C9, the negative electrode of electrochemical capacitor C9 is connected to the negative electrode of electrochemical capacitor C8 by resistance R45, the negative electrode of electrochemical capacitor C8 is also by resistance R44 ground connection, and the anode of electrochemical capacitor C8 is connected to the 4th pin of TDA2004 chip; The three-prong of TDA2004 chip is connected to the anode of electrochemical capacitor C10, the minus earth of electrochemical capacitor C10, and the three-prong of TDA2004 chip is also connected to power supply VCC+ by resistance R46; 6th pin ground connection of TDA2004 chip; 8th pin of TDA2004 chip is connected to the negative electrode of electrochemical capacitor C8 by resistance R39, the 8th pin of TDA2004 chip is also by the series arm ground connection of resistance R7, electric capacity C20; 9th pin of TDA2004 chip is connected to power supply VCC+; Tenth pin of TDA2004 chip is connected to the negative electrode of electrochemical capacitor C9 by resistance R24; 11 pin of TDA2004 chip is connected with the anode of electrochemical capacitor C12, and the negative electrode of electrochemical capacitor C12 is connected to the tenth pin of TDA2004 chip; Power supply VCC+ is also connected to the anode of electrochemical capacitor C11, the minus earth of electrochemical capacitor C11; 5th pin of TDA2004 chip is connected to the anode of electrochemical capacitor C19, and the negative electrode of electrochemical capacitor C19 is the input of audio power amplifier circuit; 8th pin of TDA2004 chip and the tenth pin are respectively as the anode of audio power amplifier circuit output and negative terminal.
9. the wireless teaching microphone circuit of band MP3 player according to claim 1, is characterized in that: also comprise reference voltage circuit; Described reference voltage circuit comprises direct current input interface; Direct current input interface is connected to the first end of resistance R8 by diode D11, second end of resistance R8 is connected to the input of 8V pressurizer Q10, the reference edge ground connection of 8V pressurizer Q10, the output of 8V pressurizer Q10 passes through the parallel branch ground connection of electrochemical capacitor C27 and electric capacity C28; The output of 8V pressurizer Q10 is also connected to the collector electrode of NPN triode Q5, the collector electrode of NPN triode Q5 is also connected to the base stage of NPN triode Q5 by resistance R15, the collector electrode of NPN triode Q5 is connected to the base stage of NPN triode Q6 by resistance R43, the base stage of NPN triode Q6 is by electrochemical capacitor C30 ground connection, the grounded emitter of NPN triode Q6, the collector electrode of NPN triode Q6 is also connected to the base stage of NPN triode Q5; The collector electrode of NPN triode Q5 is connected to the base stage of PNP triode Q11 by resistance R16, the collector electrode of NPN triode Q5 is connected to the emitter of PNP triode Q11 by diode D5, the emitter of NPN triode Q5 is connected to the collector electrode of PNP triode, the emitter of PNP triode Q11 is also by electrochemical capacitor C7 ground connection, and the collector electrode of PNP triode Q11 is also by electrochemical capacitor C31 ground connection; The collector electrode of PNP triode Q11 is connected to the base stage of NPN triode Q7 by resistance R40, the grounded emitter of NPN triode Q7, and the collector electrode of NPN triode Q7 passes through the parallel branch ground connection of electric capacity C36, resistance R55; The current collection of NPN triode Q7 very reference voltage circuit output and be connected with the input of audio power amplifier circuit.
10. the wireless teaching microphone circuit of band MP3 player according to claim 9, it is characterized in that: described diode D11 is connected with the first end of resistance R8 by selector switch S5, the negative electrode of diode D11 is connected with the common port of selector switch S5, the first end of selector switch S5 is connected with the first end of resistance R8, second end of selector switch S5 is connected with the first anode of bidirectional thyristor Q8, and the second plate of bidirectional thyristor Q8 is connected to second end of selector switch S5 by resistance R37; Second end of selector switch S5 is also connected to the positive power source terminal of amplifier AR1 and the positive power source terminal of amplifier AR2, the negative power end of amplifier AR1 and the equal ground connection of the negative power end of amplifier AR2; Second end of selector switch S5 is also connected with the positive input terminal of amplifier AR1 by resistance R52; The positive input terminal of amplifier AR1 is also connected with the anode of thyristor Q9, the negative electrode of thyristor Q9 is connected to the positive input terminal of amplifier AR1 by resistance R54, the negative electrode of thyristor Q9 is also by resistance R21 ground connection, the control pole ground connection of thyristor Q9, the negative input end of amplifier AR1 is connected to the anode of 12VDC interface J7 by resistance R48; The control pole of bidirectional thyristor Q8 is also connected to the output of amplifier AR1 by resistance R20; The anode of 12VDC interface J7 is also connected to the positive input terminal of amplifier AR2 by resistance R49, the negative input end of amplifier AR2 is connected to the anode of light-emitting diode D13 by resistance R61, the minus earth of light-emitting diode D13, the output of amplifier AR2 is connected to the output of amplifier AR1 by resistance R47; The negativing ending grounding of 12VDC interface J7; The first end of selector switch S5 is also connected to the common port of selector switch S5 by the series arm of resistance R53, diode D9, diode D12; The 0V pin of power supply wire jumper interface J6 is connected with the common port of selector switch S5 with the parallel branch of electric capacity C25 by diode D7, electric capacity C24, diode D8, wherein the anode of diode D7, the anode of diode D8 are connected with the 0V pin of power supply wire jumper interface J6, the 0V pin of power supply wire jumper interface J6 is also by the parallel branch ground connection of electric capacity C23 and diode D6, and wherein the negative electrode of diode D6 is connected with the 0V pin of power supply wire jumper interface J6; The common port of selector switch S5 is also connected to the anode of electrochemical capacitor C26, the minus earth of electrochemical capacitor C26.
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| CN201310561700.3A CN104640015B (en) | 2013-11-12 | 2013-11-12 | Wireless teaching microphone circuit with MP3 player |
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| CN201310561700.3A CN104640015B (en) | 2013-11-12 | 2013-11-12 | Wireless teaching microphone circuit with MP3 player |
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| WO2004091185A2 (en) * | 2003-03-31 | 2004-10-21 | Guilhem Doucet | Sound amplification device for the hard of hearing |
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| WO2004091185A2 (en) * | 2003-03-31 | 2004-10-21 | Guilhem Doucet | Sound amplification device for the hard of hearing |
| CN201004706Y (en) * | 2007-01-20 | 2008-01-09 | 魏军 | Intelligent transmitter with MP3 |
| CN201590807U (en) * | 2010-01-21 | 2010-09-22 | 宁波利声音响器材有限公司 | Power amplifier with playing function of MP3 (Moving Picture Experts Group Audio Layer-3) |
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