CN203786894U - Remote control signal processing circuit of loudspeaker box as well as loudspeaker box - Google Patents
Remote control signal processing circuit of loudspeaker box as well as loudspeaker box Download PDFInfo
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- CN203786894U CN203786894U CN201420138751.5U CN201420138751U CN203786894U CN 203786894 U CN203786894 U CN 203786894U CN 201420138751 U CN201420138751 U CN 201420138751U CN 203786894 U CN203786894 U CN 203786894U
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- 238000001914 filtration Methods 0.000 claims description 14
- 239000003990 capacitor Substances 0.000 claims description 12
- 230000005540 biological transmission Effects 0.000 claims description 5
- 230000000694 effects Effects 0.000 description 5
- 230000005669 field effect Effects 0.000 description 5
- 238000010586 diagram Methods 0.000 description 4
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Abstract
The utility model discloses a remote control signal processing circuit of a loudspeaker box as well as the loudspeaker box. The circuit comprises a remote control signal receiver, a main controller, a modulation module and a transmitting module, wherein the remote control signal receiver is used for receiving a remote control signal; the main controller is used for outputting a carrier frequency and decoding the remote control signal of a loudspeaker box body; the modulation module is used for modulating the remote control signal received by the remote control signal receiver by taking the carrier frequency output by the main controller as the carrier frequency and outputting the modulation signal; the transmitting module is used for receiving the modulation signal and transmitting the modulation signal; a first input end of the modulation module is connected with a carrier frequency output end of the main controller, and a second input end of the modulation module is connected with an output end of the remote control signal receiver; an output end of the modulation module is connected with an input end of the transmitting module; an input end of the main controller is connected with an output end of the remote control signal receiver. According to the remote control signal processing circuit disclosed by the utility model, the loudspeaker box remote control processing circuit can generate a stable carrier frequency, so that the accuracy for transmitting the remote control signal by the loudspeaker box is improved.
Description
Technical field
The utility model relates to electronic product field, particularly relates to a kind of remote control signal processing circuit and audio amplifier of audio amplifier.
Background technology
Existing speaker products conventionally and televisor be used in conjunction with.Stop that the remote control reception head of televisor affects the remote control effect of televisor, arranges infrared signal transponder in the remote control signal processing circuit of audio amplifier when preventing that audio amplifier from putting.Audio amplifier receives the remote signal of the machine or the remote signal of televisor, and then judges whether this remote signal is the code value of the machine.If so, do decoding and process, complete corresponding feature operation.If not, do not deal with, forward by infrared signal transponder, pass to televisor, operated accordingly by televisor.Existing infrared transponder produces carrier frequency by RC oscillatory circuit.Because the value of resistance R and capacitor C components and parts has error, the parameter temperature influence of adding resistance R and capacitor C is larger.Therefore, the carrier frequency that RC oscillatory circuit produces is very unstable, thereby has affected the result of use of product.
Utility model content
The utility model provides a kind of remote control signal processing circuit and audio amplifier of audio amplifier, is intended to make audio amplifier remote control signal processing circuit can produce stabilized carrier frequency, thereby improves the accuracy of audio amplifier forwarding remote control signal.
To achieve these goals, the utility model provides a kind of remote control signal processing circuit of audio amplifier, the remote control signal processing circuit of this audio amplifier comprises the remote signal Receiver of the remote signal for receiving external remote transmission, the master controller that is used for outgoing carrier frequency and the remote signal of audio amplifier the machine is decoded, the modulation module of modulation signal is modulated and exported to the remote signal as carrier frequency, described remote signal Receiver being received using the carrier frequency of described master controller output, and transmitter module for receiving described modulation signal and this modulation signal being sent, wherein, described modulation module comprises first input end, the second input end and output terminal, the first input end of described modulation module is connected with the carrier frequency output terminal of described master controller, the second input end of described modulation module is connected with the output terminal of described remote signal Receiver, the output terminal of described modulation module is connected with the input end of described transmitter module, and the input end of described master controller is connected with the output terminal of described remote signal Receiver.
Preferably, described modulation module comprises the first transistor, transistor seconds, the first resistance and the second resistance, and the first end of described the first transistor is connected with described master controller as the first input end of described modulation module; The second end of described the first transistor is connected with the second end of described transistor seconds through described the first resistance; The 3rd end of described the first transistor is connected with described transmitter module as the output terminal of described modulation module, and the 3rd end of described the first transistor is connected with external dc power through described the second resistance; The first end of described transistor seconds is connected with described remote signal Receiver as the second input end of described modulation module, the 3rd end ground connection of described transistor seconds.
Preferably, described the first transistor is NPN triode, and transistor seconds is PNP triode.
Preferably, described transmitter module comprises infrarede emitting diode, and for amplifying the driver element of described modulation signal electric current, the input end of described driver element is connected with the output terminal of described modulation module, the output terminal of described driver element is connected with the negative electrode of described infrarede emitting diode, and the anode of described infrarede emitting diode is connected with external dc power.
Preferably, described driver element comprises the 3rd transistor, the 3rd resistance and the 4th resistance, described the 3rd transistorized first end is connected with the output terminal of described modulation module through the 3rd resistance, described the 3rd transistorized the second end is connected with the negative electrode of described infrarede emitting diode through described the 4th resistance, described the 3rd transistorized the 3rd end ground connection.
Preferably, described the 3rd transistor is PNP triode.
Preferably, the remote control signal processing circuit of audio amplifier also comprises the filtration module of inputting the noise signal of described modulation module for filtering, described filtration module one end is connected with the output terminal of described remote signal Receiver, and the other end is connected with the first input end of described modulation module.
Preferably, described filtration module comprises filter capacitor, and described filter capacitor one end is connected with the second input end of described modulation module, the other end ground connection of described filter capacitor.
The utility model further provides a kind of audio amplifier, this audio amplifier has the remote control signal processing circuit of audio amplifier, the remote control signal processing circuit of audio amplifier comprises the remote signal Receiver for receiving remote signal, the master controller that is used for outgoing carrier frequency and the remote signal of audio amplifier the machine is decoded, the modulation module of modulation signal is modulated and exported to the remote signal as carrier frequency, described remote signal Receiver being received using the carrier frequency of described master controller output, and transmitter module for receiving described modulation signal and this modulation signal being sent, wherein, described modulation module comprises first input end, the second input end and output terminal, the first input end of described modulation module is connected with the carrier frequency output terminal of described master controller, the second input end of described modulation module is connected with the output terminal of described remote signal Receiver, the output terminal of described modulation module is connected with the input end of described transmitter module, and the input end of described master controller is connected with the output terminal of described remote signal Receiver.
The carrier frequency that the utility model produces master controller is as the carrier frequency of forwarding remote control signal.In the time that the remote control signal processing circuit of audio amplifier receives the remote signal of external remote transmission, modulation module modulates this remote signal and master controller produces carrier frequency, and by transmitter module, the remote signal after modulation is forwarded, thereby avoid audio amplifier to stop the remote signal Receiver of televisor and the situation of the TV remote-control weak effect that causes occurs.The carrier frequency that the utility model utilizes master controller to produce is subject to the advantage that external environment influence is less, the carrier frequency that the carrier frequency that master controller is produced forwards as remote signal, overcome the unsettled shortcoming of carrier frequency that in prior art, RC oscillatory circuit produces, thus the accuracy that has improved audio amplifier forward signal.On the other hand, the utility model has effectively utilized the master controller generation carrier frequency that system carries, and simplifies the design of hardware circuit, thereby has reduced the cost of product.
Brief description of the drawings
Fig. 1 is the modular structure schematic diagram of the remote control signal processing circuit of the utility model audio amplifier;
Fig. 2 is the electrical block diagram of the remote control signal processing circuit of the utility model audio amplifier.
Realization, functional characteristics and the advantage of the utility model object, in connection with embodiment, are described further with reference to accompanying drawing.
Embodiment
Should be appreciated that specific embodiment described herein is only in order to explain the utility model, and be not used in restriction the utility model.
The utility model provides a kind of remote control signal processing circuit of audio amplifier.
With reference to Fig. 1, Fig. 1 is the modular structure schematic diagram of the remote control signal processing circuit of the utility model audio amplifier.
The remote control signal processing circuit of a kind of audio amplifier that the present embodiment provides, the remote control signal processing circuit of audio amplifier comprises remote signal Receiver 1, master controller U1, modulation module 2 and transmitter module 3.
The remote signal that remote signal Receiver 1 sends for receiving external remote.Master controller U1 is used for outgoing carrier frequency and the remote signal of audio amplifier the machine is decoded.Modulation signal is modulated and exported to the remote signal that modulation module 2 receives remote signal Receiver 1 as carrier frequency using the carrier frequency of master controller U1 output.Transmitter module 3 is for receiving modulation signal and this modulation signal being sent.Modulation module 2 comprises first input end, the second input end and output terminal.The first input end of modulation module 2 is connected with the carrier frequency output terminal of master controller U1, the second input end of modulation module 2 is connected with the output terminal of remote signal Receiver 1, the output terminal of modulation module 2 is connected with the input end of transmitter module 3, and the input end of master controller U1 is connected with the output terminal of remote signal Receiver 1.
In the present embodiment, remote signal Receiver 1 receives the remote signal sending from external remote such as TV remote controller or audio amplifier telepilots, and this remote signal is infrared remote-controlled signal.Remote signal Receiver 1 receives after infrared remote-controlled signal, does not make the processing of any this remote signal of change, but directly exports this remote signal by its output terminal.Master controller U1 is the master controller U1 that sound box system carries, master controller U1 is on the one hand to processings of decode from the remote signal of audio amplifier telepilot (for not belonging to the processing of decode of remote signal that audio amplifier telepilot sends), and controls audio amplifier execution and operate accordingly.On the other hand, master controller U1 produces carrier frequency, and the carrier frequency that is 50% in its carrier frequency output terminal output 38KHz, dutycycle.The remote signal that modulation module 2 is mainly used in remote signal Receiver 1 to export is modulated.The first input end of modulation module 2 is connected with the carrier frequency output terminal of master controller U1, for receiving the carrier frequency of master controller U1 output.The second input end of modulation module 2 is connected with the output terminal of remote signal Receiver 1, for receiving remote signal.Modulation module 2 is modulated as the carrier frequency of remote signal using the carrier frequency of master controller U1 output, and exports the modulation signal after modulation at the output terminal of modulation module 2.Transmitter module 3 receives the modulation signal that modulation module 2 is exported, and this modulation signal is transmitted on the external units such as televisor, thereby makes the external units such as televisor can receive the remote signal having been stopped by audio amplifier.
By specific embodiment, the principle of work of this circuit is described below.
In the time that remote signal Receiver 1 receives the remote signal of external remote transmission, this remote signal is sent to master controller U1 and modulation module 2 by the output terminal of remote signal Receiver 1 simultaneously.Below respectively how master controller U1 and modulation module 2 being processed to this remote signal sets forth.
Master controller U1 receives this remote signal and judges, in the time that remote signal is not the code value of the machine (audio amplifier, lower same), and master controller U1 undo.In the time that master controller U1 judges that this remote signal is the code value of the machine, master controller U1 is further to the remote signal processing of decoding, and controls audio amplifier and carry out corresponding operation.It should be noted that no matter which kind of remote signal master controller U1 receives, all the time in its carrier frequency output terminal outgoing carrier frequency, and be sent to modulation module 2.
The first input end of modulation module 2 receives the carrier frequency of master controller U1 output, and the second input end of modulation module 2 receives the remote signal that remote signal Receiver 1 is exported.Modulation module 2 is modulated to the remote signal receiving in carrier frequency, and export modulation signal to transmitter module 3, be sent to the external units such as televisor by transmitter module 3, and then realized the object that remote signal is forwarded, thereby being stopped by audio amplifier, the remote signal Receiver that has overcome televisor affects the shortcoming of remote control effect.
The carrier frequency that the utility model produces master controller U1 is as the carrier frequency of forwarding remote control signal.In the time that the remote control signal processing circuit of audio amplifier receives the remote signal of external remote transmission, modulation module 2 these remote signals of modulation and master controller U1 produce carrier frequency, and by transmitter module 3, the remote signal after modulation is forwarded, make televisor can receive remote signal, thereby avoided audio amplifier to stop the remote signal Receiver of televisor and the situation of the TV remote-control weak effect that causes occurs.The carrier frequency that the utility model utilizes master controller U1 to produce is subject to the advantage that external environment influence is less, the carrier frequency that the carrier frequency that master controller U1 is produced forwards as remote signal, overcome the unsettled shortcoming of carrier frequency that in prior art, RC oscillatory circuit produces, thus the accuracy that has improved audio amplifier forward signal.On the other hand, the utility model has effectively utilized the master controller U1 generation carrier frequency that system carries, and simplifies the design of hardware circuit, thereby has reduced the cost of product.
In conjunction with reference to Fig. 2, Fig. 2 is the electrical block diagram of the remote control signal processing circuit of the utility model audio amplifier.Further, modulation module 2 comprises the first transistor Q1, transistor seconds Q2, the first resistance R 1 and the second resistance R 2.The first end of the first transistor Q1 is connected with master controller U1 as the first input end of modulation module 2.The second end of the first transistor Q1 is connected with the second end of described transistor seconds Q2 through the first resistance R 1.The 3rd end of the first transistor Q1 is connected with transmitter module 3 as the output terminal of modulation module 2, and the 3rd end of the first transistor Q1 is connected with external dc power through the second resistance R 2.The first end of transistor seconds Q2 is connected with remote signal Receiver 1 as the second input end of modulation module 2, the 3rd end ground connection of transistor seconds Q2.
In the present embodiment, the first transistor Q1 and transistor seconds Q2 mainly play switch.The first transistor Q1 is NPN triode, and transistor seconds Q2 is PNP triode.The first end of the first transistor Q1 is base stage, and the second end is emitter, and the 3rd end is collector.The first end of transistor seconds Q2 is base stage, and the second end is emitter, and the 3rd end is collector.
The base stage of the first transistor Q1 is connected as the first input end of modulation module 2 and the carrier frequency output terminal of master controller U1.The collector of the first transistor Q1 is connected with the input end of transmitter module 3 as the output terminal of modulation module 2, and the collector of the first transistor Q1 is connected with external dc power through the second resistance R 2.The emitter of the first transistor Q1 is connected with the emitter of transistor seconds Q2 through the first resistance R 1.The base stage of transistor seconds Q2 is connected with the output terminal of remote signal Receiver 1 as the second input end of modulation module 2.The grounded collector of transistor seconds Q2.
The carrier frequency that master controller U1 produces is sent to the base stage of the first transistor Q1, and the remote signal that remote signal Receiver 1 is exported is to the base stage of transistor seconds Q2.The first transistor Q1 and transistor seconds Q2 modulate remote signal and carrier frequency, and export modulation signal at the collector of the first transistor Q1.
When the remote signal of exporting when remote signal Receiver 1 is high level, transistor seconds Q2 cut-off, the modulation signal that modulation module 2 is exported is always high level.The remote signal of exporting when remote signal Receiver 1 is carrier frequency that low level and master controller U1 are sent to the first transistor Q1 while being high level, and the modulation signal of output is low level.The remote signal of exporting when remote signal Receiver 1 is carrier frequency that low level and master controller U1 are sent to the first transistor Q1 while being low level, and the modulation signal of output is high level.The cut-off of the first transistor Q1 and transistor seconds Q2 and conducting, thus realize the object of remote signal and carrier frequency modulation.It should be noted that the first transistor Q1 and transistor seconds Q2 can be also field effect transistor.Particularly, the first transistor Q1 is N channel field-effect pipe, and transistor seconds Q2 is P-channel field-effect transistor (PEFT) pipe.Its principle of work is same as the previously described embodiments, does not repeat them here.
Further, transmitter module 3 comprises infrarede emitting diode D, and for amplifying the driver element 31 of modulation signal electric current.The input end of driver element 31 is connected with the output terminal of modulation module 2, and the output terminal of driver element 31 is connected with the negative electrode of infrarede emitting diode D.The anode of infrarede emitting diode D is connected with external dc power.
In the present embodiment, driver element 31 is for amplifying the size of current of modulation signal, and then makes the infrarede emitting diode D can be normally luminous.On the other hand, driver element 31 has played switch, by the light on and off of controlling infrarede emitting diode D, modulation signal is sent.In this enforcement, driving circuit comprises the 3rd transistor Q3, the 3rd resistance R 3 and the 4th resistance R 4.The first end of the 3rd transistor Q3 is connected with the output terminal of modulation module 2 through the 3rd resistance R 3.The second end of the 3rd transistor Q3 is connected with the negative electrode of infrarede emitting diode D through the 4th resistance R 4.The 3rd end ground connection of the 3rd transistor Q3.The 3rd transistor Q3 has played switch and amplified current in this driver element 31.The 3rd transistor Q3 is PNP triode.Particularly, the first end of the 3rd transistor Q3 is base stage, and the second end is emitter, and the 3rd end is collector.In the time that modulation signal is high level, the 3rd transistor Q3 cut-off, infrarede emitting diode D extinguishes.In the time that modulation signal is low level, the 3rd transistor Q3 conducting, infrarede emitting diode D lights.Those skilled in the art are when knowing, modulation signal control, by the light on and off of infrarede emitting diode D, can either realize the object that modulation signal is sent.This field effect transistor it should be noted that the 3rd transistor Q3 can be also field effect transistor, as long as can play the effect of switch and amplified current.
Further, the remote control signal processing circuit of audio amplifier also comprises the filtration module 4 that inputs to the noise signal of modulation module 2 for filtering, and filtration module 4 one end are connected with remote signal Receiver 1, and the other end is connected with modulation module 2.
In the present embodiment, filtration module 4 inputs to the noise signal of modulation module 2 for filtering, avoids noise signal to enter modulation module 2, thereby has effectively ensured the quality of forward signal.In the present embodiment, filtration module 4 comprises filter capacitor C, and one end of filter capacitor C is connected with the second input end of modulation module 2, the other end ground connection of filter capacitor C.Filter capacitor C directly guides to noise signal and holds, thereby has avoided noise signal to follow remote signal to enter modulation module 2, has effectively ensured the quality of forward signal.
The utility model also provides a kind of audio amplifier, and this audio amplifier comprises the remote control signal processing circuit of audio amplifier.The structure of the remote control signal processing circuit of this audio amplifier can, with reference to above-described embodiment, not repeat them here.Naturally, because the audio amplifier of the present embodiment has adopted the technical scheme of the remote control signal processing circuit of above-mentioned audio amplifier, therefore this audio amplifier has all beneficial effects of remote control signal processing circuit of above-mentioned audio amplifier.
These are only preferred embodiment of the present utility model; not thereby limit the scope of the claims of the present utility model; every equivalent structure or conversion of equivalent flow process that utilizes the utility model instructions and accompanying drawing content to do; or be directly or indirectly used in other relevant technical fields, be all in like manner included in scope of patent protection of the present utility model.
Claims (9)
1. the remote control signal processing circuit of an audio amplifier, comprise the remote signal Receiver of the remote signal for receiving external remote transmission, it is characterized in that, also comprise the master controller of decoding for outgoing carrier frequency and to the remote signal of audio amplifier the machine, the modulation module of modulation signal is modulated and exported to the remote signal as carrier frequency, described remote signal Receiver being received using the carrier frequency of described master controller output, and transmitter module for receiving described modulation signal and this modulation signal being sent;
Wherein, described modulation module comprises first input end, the second input end and output terminal, the first input end of described modulation module is connected with the carrier frequency output terminal of described master controller, the second input end of described modulation module is connected with the output terminal of described remote signal Receiver, the output terminal of described modulation module is connected with the input end of described transmitter module, and the input end of described master controller is connected with the output terminal of described remote signal Receiver.
2. the remote control signal processing circuit of audio amplifier as claimed in claim 1, it is characterized in that, described modulation module comprises the first transistor, transistor seconds, the first resistance and the second resistance, and the first end of described the first transistor is connected with described master controller as the first input end of described modulation module; The second end of described the first transistor is connected with the second end of described transistor seconds through described the first resistance; The 3rd end of described the first transistor is connected with described transmitter module as the output terminal of described modulation module, and the 3rd end of described the first transistor is connected with external dc power through described the second resistance; The first end of described transistor seconds is connected with described remote signal Receiver as the second input end of described modulation module, the 3rd end ground connection of described transistor seconds.
3. the remote control signal processing circuit of audio amplifier as claimed in claim 2, is characterized in that, described the first transistor is NPN triode, and transistor seconds is PNP triode.
4. the remote control signal processing circuit of audio amplifier as claimed in claim 1, it is characterized in that, described transmitter module comprises infrarede emitting diode, and for amplifying the driver element of described modulation signal electric current, the input end of described driver element is connected with the output terminal of described modulation module, the output terminal of described driver element is connected with the negative electrode of described infrarede emitting diode, and the anode of described infrarede emitting diode is connected with external dc power.
5. the remote control signal processing circuit of audio amplifier as claimed in claim 4, it is characterized in that, described driver element comprises the 3rd transistor, the 3rd resistance and the 4th resistance, described the 3rd transistorized first end is connected with the output terminal of described modulation module through the 3rd resistance, described the 3rd transistorized the second end is connected with the negative electrode of described infrarede emitting diode through described the 4th resistance, described the 3rd transistorized the 3rd end ground connection.
6. the remote control signal processing circuit of audio amplifier as claimed in claim 5, is characterized in that, described the 3rd transistor is PNP triode.
7. the remote control signal processing circuit of the audio amplifier as described in claim 1 to 6 any one, it is characterized in that, also comprise the filtration module of inputting the noise signal of described modulation module for filtering, described filtration module one end is connected with the output terminal of described remote signal Receiver, and the other end is connected with the first input end of described modulation module.
8. the remote control signal processing circuit of audio amplifier as claimed in claim 7, is characterized in that, described filtration module comprises filter capacitor, and described filter capacitor one end is connected with the second input end of described modulation module, the other end ground connection of described filter capacitor.
9. an audio amplifier, is characterized in that, comprises the remote control signal processing circuit of the audio amplifier as described in claim 1 to 8 any one.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420138751.5U CN203786894U (en) | 2014-03-25 | 2014-03-25 | Remote control signal processing circuit of loudspeaker box as well as loudspeaker box |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201420138751.5U CN203786894U (en) | 2014-03-25 | 2014-03-25 | Remote control signal processing circuit of loudspeaker box as well as loudspeaker box |
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| Publication Number | Publication Date |
|---|---|
| CN203786894U true CN203786894U (en) | 2014-08-20 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201420138751.5U Expired - Lifetime CN203786894U (en) | 2014-03-25 | 2014-03-25 | Remote control signal processing circuit of loudspeaker box as well as loudspeaker box |
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Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111343491A (en) * | 2020-04-26 | 2020-06-26 | 中山市悦辰电子实业有限公司 | Remote control intermediate transfer control circuit |
-
2014
- 2014-03-25 CN CN201420138751.5U patent/CN203786894U/en not_active Expired - Lifetime
Cited By (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN111343491A (en) * | 2020-04-26 | 2020-06-26 | 中山市悦辰电子实业有限公司 | Remote control intermediate transfer control circuit |
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Granted publication date: 20140820 |