CN205039780U - Take dual power supply's dual track audio power amplifier circuit - Google Patents
Take dual power supply's dual track audio power amplifier circuit Download PDFInfo
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- CN205039780U CN205039780U CN201520735997.5U CN201520735997U CN205039780U CN 205039780 U CN205039780 U CN 205039780U CN 201520735997 U CN201520735997 U CN 201520735997U CN 205039780 U CN205039780 U CN 205039780U
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Abstract
The utility model discloses a take dual power supply's dual track audio power amplifier circuit, including audio power amplifier circuit and power supply circuit, audio power amplifier circuit connection power supply circuit, power supply circuit include fixed power VCC, are used for to connect external DC power supply's power supply terminal DC, power filter capacitance C11, power indication circuit, and power filter capacitance C11 one end is passed through switch K1 and is connected with fixed power VCC's positive pole, and power filter capacitance C11's the other end is connected with fixed power VCC's negative pole, the power indication circuit is including the LED and the resistance R5 that connect gradually, and resistance R5 is connected with fixed power VCC's negative pole, and LED's positive pole passes through switch K1 and is connected with fixed power VCC's positive pole, power supply terminal DC and fixed power VCC connect, can use multiple mode to provide the special dual power supply's who sets up of convertible power as audio power dual track audio power amplifier circuit.
Description
Technical field
The utility model relates to electronic circuit technology field, specifically, is a kind of dual-channel audio amplifying circuit with dual power supply.
Background technology
The object of audio frequency amplifier is the audio signal of rebuilding input on sonorific output element, and signal volume and power stage all want desirable---strictly according to the facts, effectively and distortion is low.Audiorange is about 20Hz ~ 20kHz, and therefore amplifier must have good frequency response (smaller during the loud speaker driving frequency band limited, as bass horn or loudspeaker) within the scope of this.According to the difference of application, watt level is widely different, several watts from the milliwatt level of earphone to TV or PC audio frequency, tens watts that arrive " mini " home stereo and automobile audio again, until more than hundreds of watts of more powerful family expenses and commercial sound system, large to the sound requirement that can meet whole cinema or auditorium.
A kind of simple analog implementation of audio frequency amplifier is the transistor adopting linear model, obtains the output voltage proportional with input voltage.Forward voltage gain usually very high (at least 40dB).If feedback loop comprises forward gain, then whole ring gain is also very high.Because high loop gain energy improving SNR, can suppress by the non-linear distortion caused of forward path, and reduce power supply noise, so often adopt feedback by improving power supply rejection ability (PSR).
Utility model content
The purpose of this utility model is to provide a kind of dual-channel audio amplifying circuit with dual power supply, when carrying out audio frequency and amplifying, can effectively be provided for the power supply being converted to audio power, and the dual-channel audio amplifying circuit of the power supply that can be exchanged into audio power and the dual power supply arranged especially can be provided in many ways, in use, can effectively filtering the interference signals such as contained harmonic wave are provided in power supply, and there is real-time monitored to power whether normal function.
The utility model is achieved through the following technical solutions: a kind of dual-channel audio amplifying circuit with dual power supply, comprise audio amplifier circuit and power circuit, described audio amplifier circuit connects power circuit, described power circuit comprises fixed power source VCC, for connecting power supply terminal DC, power filtering capacitor C11, the power indicating circuit of external direct current power supply, described power filtering capacitor C11 one end is connected with the positive pole of fixed power source VCC by K switch 1, and the other end of power filtering capacitor C11 is connected with the negative pole of fixed power source VCC; Described power indicating circuit comprises the LED and resistance R5 that connect successively, and resistance R5 is connected with the negative pole of fixed power source VCC, and the positive pole of LED is connected with the positive pole of fixed power source VCC by K switch 1; Described power supply terminal DC and fixed power source VCC also connects.
Further for better to realize the utility model, be arranged to following structure especially: described audio amplifier circuit comprises low-power audio amplifier IC1 and dual-channel audio playing circuit, described low-power audio amplifier IC1 connects dual-channel audio playing circuit, described electric capacity C11 adopts electrochemical capacitor, and positive terminal connects 2 pin of low-power audio amplifier IC1 and the positive pole of LED respectively; The negative pole of described fixed power source VCC connects 4 pin of low-power audio amplifier IC1; Wherein, small audio signal is carried out power amplification by described low-power audio amplifier IC1; Audio signal after power amplification is reduced to binaural sound and plays by described dual-channel audio playing circuit.
Further for better to realize the utility model, be arranged to following structure especially: on described low-power audio amplifier IC1, be also provided with front end input circuit, described front end input circuit comprises the first sound channel input circuit and second sound channel input circuit, on 5 pin that described first sound channel input circuit is connected to low-power audio amplifier IC1 and 6 pin; On 7 pin that described second sound channel input circuit is connected to low-power audio amplifier IC1 and 8 pin.
Further for better to realize the utility model, be arranged to following structure especially: described first sound channel input circuit comprises the reverse input circuit of the first sound channel and the first sound channel input circuit in the same way, the reverse input circuit of described first sound channel comprises electric capacity C6, and described electric capacity C6 is connected on 5 pin of low-power audio amplifier IC1; Described first sound channel in the same way input circuit comprises resistance R2, electric capacity C4, resistance R5, and described resistance R2 connects electric capacity C4, described electric capacity C4 contact resistance R5, and electric capacity C4 and resistance R5 is all connected to 6 pin of low-power audio amplifier IC1; Described first sound channel input circuit is also provided with potentiometer W2, and the adjustable end of described potentiometer W2 is connected with resistance R2, and a stiff end of described potentiometer W2 is connected with resistance R5 and electric capacity C6 respectively.
Further for better to realize the utility model, be arranged to following structure especially: described second sound channel input circuit comprises the reverse input circuit of second sound channel and second sound channel input circuit in the same way, the reverse input circuit of described second sound channel comprises electric capacity C5, and described electric capacity C5 is connected on 8 pin of low-power audio amplifier IC1; Described first sound channel in the same way input circuit comprises resistance R1, electric capacity C2, resistance R7, and described resistance R1 connects electric capacity C2, described electric capacity C2 contact resistance R7, and electric capacity C2 and resistance R7 is all connected to 7 pin of low-power audio amplifier IC1; Described second sound channel input circuit is also provided with potentiometer W1, and the adjustable end of described potentiometer W1 is connected with resistance R1, and a stiff end of described potentiometer W1 is connected with resistance R7 and electric capacity C5 respectively.
Further for better to realize the utility model, be arranged to following structure especially: described dual-channel audio playing circuit comprises first sound channel audio playing circuit and second sound channel audio playing circuit, described first sound channel audio playing circuit connects 3 pin of low-power audio amplifier IC1, and described second sound channel audio playing circuit connects 2 pin of low-power audio amplifier IC1.
Further for better to realize the utility model, be arranged to following structure especially: described first sound channel audio playing circuit comprises resistance R3, electric capacity C8, electric capacity C7 and loud speaker RA, one end of described loud speaker RA is connected with 1 pin of low-power audio amplifier IC1 by electric capacity C8, and the other end of described loud speaker RA is connected with 1 pin of low-power audio amplifier IC1 by electric capacity C7 and resistance R3.
Further for better to realize the utility model, be arranged to following structure especially: described second sound channel audio playing circuit comprises resistance R4, electric capacity C10, electric capacity C9 and loud speaker RB, one end of described loud speaker RB is connected with 3 pin of low-power audio amplifier IC1 by electric capacity C10, and the other end of described loud speaker RB is connected with 3 pin of low-power audio amplifier IC1 by electric capacity C9 and resistance R4.
Further for better to realize the utility model, be arranged to following structure especially: described electric capacity C5, electric capacity C6, electric capacity C8 and electric capacity C10 all adopt electrochemical capacitor.
Further for better to realize the utility model, be arranged to following structure especially: one end all ground connection that one end that described loud speaker RB is connected with electric capacity C9 and loud speaker RA are connected with electric capacity C7.
The utility model compared with prior art, has the following advantages and beneficial effect:
The utility model is when carrying out audio frequency and amplifying, can effectively be provided for the power supply being converted to audio power, and the dual-channel audio amplifying circuit of the power supply that can be exchanged into audio power and the dual power supply arranged especially can be provided in many ways, in use, can effectively filtering the interference signals such as contained harmonic wave are provided in power supply, and there is real-time monitored to power whether normal function.
The utility model is small audio signal amplified, and be reduced to voice signal, and the specially designed audio amplifier circuit with dual track function, received audio signal being amplified of energy high-fidelity, high-gain is reduced to voice signal, whole circuit has the characteristics such as structure is simple, economical and practical, can obtain stereo sound yupin effect.
Accompanying drawing explanation
Fig. 1 is schematic diagram of the present utility model.
Embodiment
Below in conjunction with embodiment, the utility model is described in further detail, but execution mode of the present utility model is not limited thereto.
Embodiment 1:
A kind of dual-channel audio amplifying circuit with dual power supply, when carrying out audio frequency and amplifying, can effectively be provided for the power supply being converted to audio power, and the dual-channel audio amplifying circuit of the power supply that can be exchanged into audio power and the dual power supply arranged especially can be provided in many ways, in use, can effectively filtering the interference signals such as contained harmonic wave are provided in power supply, and there is real-time monitored to power whether normal function, as shown in Figure 1, be provided with following structure especially: comprise audio amplifier circuit and power circuit, described audio amplifier circuit connects power circuit, described power circuit comprises fixed power source VCC, for connecting the power supply terminal DC of external direct current power supply, power filtering capacitor C11, power indicating circuit, described power filtering capacitor C11 one end is connected with the positive pole of fixed power source VCC by K switch 1, and the other end of power filtering capacitor C11 is connected with the negative pole of fixed power source VCC, described power indicating circuit comprises the LED and resistance R5 that connect successively, and resistance R5 is connected with the negative pole of fixed power source VCC, and the positive pole of LED is connected with the positive pole of fixed power source VCC by K switch 1, described power supply terminal DC and fixed power source VCC also connects.
Embodiment 2:
The present embodiment is at the enterprising one-step optimization in the basis of above-described embodiment, further for better to realize the utility model, as described in Figure 1, be arranged to following structure especially: described audio amplifier circuit comprises low-power audio amplifier IC1 and dual-channel audio playing circuit, described low-power audio amplifier IC1 connects dual-channel audio playing circuit, described electric capacity C11 adopts electrochemical capacitor, and positive terminal connects 2 pin of low-power audio amplifier IC1 and the positive pole of LED respectively; The negative pole of described fixed power source VCC connects 4 pin of low-power audio amplifier IC1; Wherein, small audio signal is carried out power amplification by described low-power audio amplifier IC1; Audio signal after power amplification is reduced to binaural sound and plays by described dual-channel audio playing circuit.
Embodiment 3:
The present embodiment is at the enterprising one-step optimization in the basis of above-described embodiment, further for better to realize the utility model, as shown in Figure 1, be arranged to following structure especially: on described low-power audio amplifier IC1, be also provided with front end input circuit, described front end input circuit comprises the first sound channel input circuit and second sound channel input circuit, on 5 pin that described first sound channel input circuit is connected to low-power audio amplifier IC1 and 6 pin; On 7 pin that described second sound channel input circuit is connected to low-power audio amplifier IC1 and 8 pin.
Embodiment 4:
The present embodiment is at the enterprising one-step optimization in the basis of above-described embodiment, further for better to realize the utility model, as shown in Figure 1, be arranged to following structure especially: described first sound channel input circuit comprises the reverse input circuit of the first sound channel and the first sound channel input circuit in the same way, the reverse input circuit of described first sound channel comprises electric capacity C6, and described electric capacity C6 is connected on 5 pin of low-power audio amplifier IC1; Described first sound channel in the same way input circuit comprises resistance R2, electric capacity C4, resistance R5, and described resistance R2 connects electric capacity C4, described electric capacity C4 contact resistance R5, and electric capacity C4 and resistance R5 is all connected to 6 pin of low-power audio amplifier IC1; Described first sound channel input circuit is also provided with potentiometer W2, and the adjustable end of described potentiometer W2 is connected with resistance R2, and a stiff end of described potentiometer W2 is connected with resistance R5 and electric capacity C6 respectively.
Embodiment 5:
The present embodiment is the enterprising one-step optimization in basis in embodiment 3 or 4, further for better to realize the utility model, as shown in Figure 1, be arranged to following structure especially: described second sound channel input circuit comprises the reverse input circuit of second sound channel and second sound channel input circuit in the same way, the reverse input circuit of described second sound channel comprises electric capacity C5, and described electric capacity C5 is connected on 8 pin of low-power audio amplifier IC1; Described first sound channel in the same way input circuit comprises resistance R1, electric capacity C2, resistance R7, and described resistance R1 connects electric capacity C2, described electric capacity C2 contact resistance R7, and electric capacity C2 and resistance R7 is all connected to 7 pin of low-power audio amplifier IC1; Described second sound channel input circuit is also provided with potentiometer W1, and the adjustable end of described potentiometer W1 is connected with resistance R1, and a stiff end of described potentiometer W1 is connected with resistance R7 and electric capacity C5 respectively.
Embodiment 6:
The present embodiment is at the enterprising one-step optimization in the basis of embodiment 2-5 any embodiment, further for better to realize the utility model, as shown in Figure 1, be arranged to following structure especially: described dual-channel audio playing circuit comprises first sound channel audio playing circuit and second sound channel audio playing circuit, described first sound channel audio playing circuit connects 3 pin of low-power audio amplifier IC1, and described second sound channel audio playing circuit connects 2 pin of low-power audio amplifier IC1.
Embodiment 7:
The present embodiment is at the enterprising one-step optimization in the basis of above-described embodiment, further for better to realize the utility model, as shown in Figure 1, be arranged to following structure especially: described first sound channel audio playing circuit comprises resistance R3, electric capacity C8, electric capacity C7 and loud speaker RA, one end of described loud speaker RA is connected with 1 pin of low-power audio amplifier IC1 by electric capacity C8, and the other end of described loud speaker RA is connected with 1 pin of low-power audio amplifier IC1 by electric capacity C7 and resistance R3.
Embodiment 8:
The present embodiment is the enterprising one-step optimization in basis in embodiment 6 or 7, further for better to realize the utility model, as shown in Figure 1, be arranged to following structure especially: described second sound channel audio playing circuit comprises resistance R4, electric capacity C10, electric capacity C9 and loud speaker RB, one end of described loud speaker RB is connected with 3 pin of low-power audio amplifier IC1 by electric capacity C10, and the other end of described loud speaker RB is connected with 3 pin of low-power audio amplifier IC1 by electric capacity C9 and resistance R4.
Embodiment 9:
The present embodiment is at the enterprising one-step optimization in the basis of above-described embodiment, further for better to realize the utility model, as shown in Figure 1, is arranged to following structure especially: described electric capacity C5, electric capacity C6, electric capacity C8 and electric capacity C10 all adopt electrochemical capacitor; The positive electrode of described electric capacity C5 connects 8 pin of low-power audio amplifier IC1, the positive electrode of electric capacity C6 connects 5 pin of low-power audio amplifier IC1, the positive electrode of electric capacity C8 connects 1 pin of low-power audio amplifier IC1, and the positive electrode of electric capacity C10 connects 4 pin of low-power audio amplifier IC1.
Embodiment 10:
The present embodiment is the enterprising one-step optimization in basis in embodiment 8 or 9, further for better to realize the utility model, as shown in Figure 1, following structure is arranged to especially: one end all ground connection that one end that described loud speaker RB is connected with electric capacity C9 and loud speaker RA are connected with electric capacity C7.
In use, left channel audio signal L-IN accesses through another stiff end of potentiometer W1; Right channel audio signal R-IN accesses through another stiff end of potentiometer W2.
The above; it is only preferred embodiment of the present utility model; not do any pro forma restriction to the utility model, every any simple modification, equivalent variations done above embodiment according to technical spirit of the present utility model, all falls within protection range of the present utility model.
Claims (10)
1. the dual-channel audio amplifying circuit with dual power supply, it is characterized in that: comprise audio amplifier circuit and power circuit, described audio amplifier circuit connects power circuit, described power circuit comprises fixed power source VCC, for connecting power supply terminal DC, power filtering capacitor C11, the power indicating circuit of external direct current power supply, described power filtering capacitor C11 one end is connected with the positive pole of fixed power source VCC by K switch 1, and the other end of power filtering capacitor C11 is connected with the negative pole of fixed power source VCC; Described power indicating circuit comprises the LED and resistance R5 that connect successively, and resistance R5 is connected with the negative pole of fixed power source VCC, and the positive pole of LED is connected with the positive pole of fixed power source VCC by K switch 1; Described power supply terminal DC and fixed power source VCC also connects.
2. a kind of dual-channel audio amplifying circuit with dual power supply according to claim 1, it is characterized in that: described audio amplifier circuit comprises low-power audio amplifier IC1 and dual-channel audio playing circuit, described low-power audio amplifier IC1 connects dual-channel audio playing circuit, described electric capacity C11 adopts electrochemical capacitor, and positive terminal connects 2 pin of low-power audio amplifier IC1 and the positive pole of LED respectively; The negative pole of described fixed power source VCC connects 4 pin of low-power audio amplifier IC1; Wherein, small audio signal is carried out power amplification by described low-power audio amplifier IC1; Audio signal after power amplification is reduced to binaural sound and plays by described dual-channel audio playing circuit.
3. a kind of dual-channel audio amplifying circuit with dual power supply according to claim 2, it is characterized in that: on described low-power audio amplifier IC1, be also provided with front end input circuit, described front end input circuit comprises the first sound channel input circuit and second sound channel input circuit, on 5 pin that described first sound channel input circuit is connected to low-power audio amplifier IC1 and 6 pin; On 7 pin that described second sound channel input circuit is connected to low-power audio amplifier IC1 and 8 pin.
4. a kind of dual-channel audio amplifying circuit with dual power supply according to claim 3, it is characterized in that: described first sound channel input circuit comprises the reverse input circuit of the first sound channel and the first sound channel input circuit in the same way, the reverse input circuit of described first sound channel comprises electric capacity C6, and described electric capacity C6 is connected on 5 pin of low-power audio amplifier IC1; Described first sound channel in the same way input circuit comprises resistance R2, electric capacity C4, resistance R5, and described resistance R2 connects electric capacity C4, described electric capacity C4 contact resistance R5, and electric capacity C4 and resistance R5 is all connected to 6 pin of low-power audio amplifier IC1; Described first sound channel input circuit is also provided with potentiometer W2, and the adjustable end of described potentiometer W2 is connected with resistance R2, and a stiff end of described potentiometer W2 is connected with resistance R5 and electric capacity C6 respectively.
5. a kind of dual-channel audio amplifying circuit with dual power supply according to claim 4, it is characterized in that: described second sound channel input circuit comprises the reverse input circuit of second sound channel and second sound channel input circuit in the same way, the reverse input circuit of described second sound channel comprises electric capacity C5, and described electric capacity C5 is connected on 8 pin of low-power audio amplifier IC1; Described first sound channel in the same way input circuit comprises resistance R1, electric capacity C2, resistance R7, and described resistance R1 connects electric capacity C2, described electric capacity C2 contact resistance R7, and electric capacity C2 and resistance R7 is all connected to 7 pin of low-power audio amplifier IC1; Described second sound channel input circuit is also provided with potentiometer W1, and the adjustable end of described potentiometer W1 is connected with resistance R1, and a stiff end of described potentiometer W1 is connected with resistance R7 and electric capacity C5 respectively.
6. a kind of dual-channel audio amplifying circuit with dual power supply according to claim 5, it is characterized in that: described dual-channel audio playing circuit comprises first sound channel audio playing circuit and second sound channel audio playing circuit, described first sound channel audio playing circuit connects 3 pin of low-power audio amplifier IC1, and described second sound channel audio playing circuit connects 2 pin of low-power audio amplifier IC1.
7. a kind of dual-channel audio amplifying circuit with dual power supply according to claim 6, it is characterized in that: described first sound channel audio playing circuit comprises resistance R3, electric capacity C8, electric capacity C7 and loud speaker RA, one end of described loud speaker RA is connected with 1 pin of low-power audio amplifier IC1 by electric capacity C8, and the other end of described loud speaker RA is connected with 1 pin of low-power audio amplifier IC1 by electric capacity C7 and resistance R3.
8. a kind of dual-channel audio amplifying circuit with dual power supply according to claim 6 or 7, it is characterized in that: described second sound channel audio playing circuit comprises resistance R4, electric capacity C10, electric capacity C9 and loud speaker RB, one end of described loud speaker RB is connected with 3 pin of low-power audio amplifier IC1 by electric capacity C10, and the other end of described loud speaker RB is connected with 3 pin of low-power audio amplifier IC1 by electric capacity C9 and resistance R4.
9. a kind of dual-channel audio amplifying circuit with dual power supply according to claim 8, is characterized in that: described electric capacity C5, electric capacity C6, electric capacity C8 and electric capacity C10 all adopt electrochemical capacitor.
10. a kind of dual-channel audio amplifying circuit with dual power supply according to claim 8, is characterized in that: one end all ground connection that one end that described loud speaker RB is connected with electric capacity C9 and loud speaker RA are connected with electric capacity C7.
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CN201520735997.5U CN205039780U (en) | 2015-09-22 | 2015-09-22 | Take dual power supply's dual track audio power amplifier circuit |
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CN201520735997.5U CN205039780U (en) | 2015-09-22 | 2015-09-22 | Take dual power supply's dual track audio power amplifier circuit |
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CN201520735997.5U Expired - Fee Related CN205039780U (en) | 2015-09-22 | 2015-09-22 | Take dual power supply's dual track audio power amplifier circuit |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105119577A (en) * | 2015-09-22 | 2015-12-02 | 成都乐维斯科技有限公司 | Dual-track audio amplification circuit powered by dual power supplies |
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Cited By (1)
Publication number | Priority date | Publication date | Assignee | Title |
---|---|---|---|---|
CN105119577A (en) * | 2015-09-22 | 2015-12-02 | 成都乐维斯科技有限公司 | Dual-track audio amplification circuit powered by dual power supplies |
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Granted publication date: 20160217 Termination date: 20160922 |
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