CN104581505A - Sound box with USB interface and control method of sound box - Google Patents
Sound box with USB interface and control method of sound box Download PDFInfo
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- CN104581505A CN104581505A CN201510018384.4A CN201510018384A CN104581505A CN 104581505 A CN104581505 A CN 104581505A CN 201510018384 A CN201510018384 A CN 201510018384A CN 104581505 A CN104581505 A CN 104581505A
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Abstract
The invention is suitable for the technical field of sound boxes, and provides a sound box with a USB interface. The sound box comprises the USB interface, an audio interface, an audio processing chip, an audio power amplifying chip and a loudspeaker. When the audio interface is in a suspended state, the audio processing chip converts audio data into digital audio signals according to a first control signal and sends the digital audio signals to the audio power amplifying chip, and the audio power amplifying chip conducts amplifying and digital-analog converting on the digital audio signals according to the first control signal and sends the amplified analog audio signals to the loudspeaker; when an audio plug is connected into the audio interface, the audio processing chip is in a shutdown state according to a second control signal, the audio power amplifying chip amplifies the analog audio signals according to the second control signal and sends the amplified signals to the loudspeaker; the USB mode can be selected to be used as the connecting mode for inputting signals and can also be selected for power supply, an audio line is used for input, the sound box can be conveniently operated by a user, and the high-quality transmission tone quality can be achieved.
Description
Technical field
The present invention relates to sound technique field, particularly relate to a kind of sound equipment and the control method thereof with USB interface.
Background technology
Along with the development of portable audio, user more and more uses tabletop sound, portable audio of the prior art adopts USB interface to provide power supply usually, the power supply capacity of USB interface is also from 500mA, rise to 1A, peak power output can reach 5 watts, the portable audio that current employing USB powers, as shown in Figure 1, comprise: a USB line, a tone frequency channel wire, audio frequency power amplifier chip, sound chamber and loudspeaker, USB line provides the power supply of 5V to audio frequency power amplifier chip from main USB controller (as computer), audio signal inputs to audio frequency power amplifier chip from computer etc., after audio frequency power amplifier chip amplifies audio signal, drive loudspeaker to sound.But this traditional USB sound equipment, exists two problems, one is needs two lines, and wherein USB line is used for power supply, and another root tone frequency channel wire is used for transmission of audio signal, and the utilance of two lines is lower; Other problem is the simulated audio signal of tone frequency channel wire transmission, simulated audio signal is subject to extraneous noise jamming in transmitting procedure, and during the audio signal analog signal output of computer own, signal to noise ratio (SNR) can reduce, generally can be reduced to about 70dB, add extraneous interference, SNR can be reduced to about 66dB, very large to tonequality damage, and the SNR theoretical value of 16 bit digital audio signals of current common use is 96dB.In sum, there is the utilance of tone frequency channel wire and USB line in prior art low and use tone frequency channel wire can cause the problem of damage to tonequality.
Summary of the invention
The object of the present invention is to provide a kind of sound equipment and the control method thereof with USB interface, low and use tone frequency channel wire can cause the problem of damage to tonequality to solve in prior art the utilance that there is tone frequency channel wire and USB line.
The invention provides a kind of sound equipment with USB interface, described sound equipment comprises USB interface, audio interface, audio processing chip, audio frequency power amplifier chip and loud speaker;
The data input pin of described audio processing chip is connected described USB interface with voltage input end, the control end of described audio processing chip connects described audio interface, the data output end of described audio processing chip connects the digital audio signal input of described audio frequency power amplifier chip, the voltage input end of described audio frequency power amplifier chip connects described USB interface, the simulated audio signal input of described audio frequency power amplifier chip is connected described audio interface with control end, and the output of described audio frequency power amplifier chip connects described loud speaker;
When described USB interface is connected with external equipment, the voltage exported by described external equipment is described audio processing chip and described audio frequency power amplifier chip power supply, and the voice data that described external equipment exports is sent to described audio processing chip;
The first control signal is generated when described audio interface is in vacant state, described first control signal is sent to described audio processing chip and described audio frequency power amplifier chip by described audio interface, described audio processing chip converts described voice data to digital audio and video signals according to described first control signal, and described digital audio and video signals is sent to described audio frequency power amplifier chip, described audio frequency power amplifier chip is sent to described loud speaker after described digital audio and video signals being carried out amplification and digital-to-analogue conversion according to described first control signal;
The second control signal is generated when described audio interface accessing to audio plug, described second control signal is sent to described audio processing chip and described audio frequency power amplifier chip by described audio interface, and the simulated audio signal that described external equipment sends is sent to described audio frequency power amplifier chip, described audio processing chip is in off state according to described second control signal, and described audio frequency power amplifier chip is sent to described loud speaker after being amplified by described simulated audio signal.
Described audio frequency power amplifier chip comprises analog signal amplifier, digital signal amplifier, digital to analog converter and driver;
The input of described analog signal amplifier is the simulated audio signal input of described audio frequency power amplifier chip, the output of described analog signal amplifier connects the first input end of described driver, the input of described digital signal amplifier is the digital audio signal input of described audio frequency power amplifier chip, the output of described digital signal amplifier connects the input of described digital to analog converter, the output of described digital to analog converter connects the second input of described driver, and the output of described driver is the output of described audio frequency power amplifier chip.
Described audio interface comprises earth terminal, the first signal end, secondary signal end and the 3rd signal end;
When described audio interface accessing to audio plug, the ground wire of described audio jack, described earth terminal and described first signal end are interconnected, and are low level second control signal to generate level.
Described audio interface also comprises pull-up circuit, and described pull-up circuit is connected with described first signal end;
When described audio interface is in vacant state, described pull-up circuit generates the second control signal that level is high level.
The present invention also provides a kind of and it is characterized in that based on the above-mentioned control method with the sound equipment of USB interface, and described control method comprises the following steps:
When described USB interface is connected with external equipment, the voltage exported by described external equipment is described audio processing chip and described audio frequency power amplifier chip power supply, and the voice data that described external equipment exports is sent to described audio processing chip;
The first control signal is generated when described audio interface is in vacant state, described first control signal is sent to described audio processing chip and described audio frequency power amplifier chip by described audio interface, described audio processing chip converts described voice data to digital audio and video signals according to described first control signal, and described digital audio and video signals is sent to described audio frequency power amplifier chip;
Described audio frequency power amplifier chip is sent to described loud speaker after described digital audio and video signals being carried out amplification and digital-to-analogue conversion according to described first control signal;
The second control signal is generated when described audio interface accessing to audio plug, described second control signal is sent to described audio processing chip and described audio frequency power amplifier chip by described audio interface, and the simulated audio signal that described external equipment sends is sent to described audio frequency power amplifier chip, described audio processing chip is in off state according to described second control signal;
Described audio frequency power amplifier chip is sent to described loud speaker after being amplified by described simulated audio signal.
Described audio interface comprises earth terminal, the first signal end, secondary signal end and the 3rd signal end;
The step generating the second control signal during described audio interface accessing to audio plug is specially:
The ground wire of described audio jack, described earth terminal and described first signal end are interconnected, and are low level second control signal to generate level.
Described audio interface also comprises pull-up circuit, and described pull-up circuit is connected with described first signal end;
Described audio interface generates the first control signal step when being in vacant state is specially:
Described pull-up circuit generates the second control signal that level is high level.
A kind of sound equipment and control method thereof with USB interface provided by the invention, according to the control signal that audio interface sends, both can choice for use USB as the connected mode of input signal, support plug and play under windows system; Also can select USB as power supply simultaneously, use tone frequency channel wire as input, use as traditional sound equipment, a tone frequency channel wire can be saved when connecting computer USB interface, user-friendly, can realize high-quality transmission tonequality, lossless audio transmits, simplify the operation of user simultaneously, and reduce the requirement to audio frequency output performances such as computers.
Accompanying drawing explanation
In order to be illustrated more clearly in the technical scheme in the embodiment of the present invention, 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 structure chart with the sound equipment of USB interface that prior art provides;
Fig. 2 is a kind of structural representation with the sound equipment of USB interface that an embodiment of the present invention provides;
Fig. 3 is the structural representation of a kind of audio frequency power amplifier chip had in the sound equipment of USB interface that an embodiment of the present invention provides;
Fig. 4 is the structural representation of a kind of audio interface accessing to audio joint had in the sound equipment of USB interface that an embodiment of the present invention provides;
Fig. 5 is a kind of flow chart with the control method of the sound equipment of USB interface that an embodiment of the present invention provides;
Fig. 6 is a kind of another flow chart with the control method of the sound equipment of USB interface that an embodiment of the present invention provides.
Embodiment
In order to make object of the present invention, technical scheme and advantage clearly understand, below in conjunction with drawings and Examples, the present invention is further elaborated.Should be appreciated that specific embodiment described herein only in order to explain the present invention, be not intended to limit the present invention.
In order to technical scheme of the present invention is described, be described below by specific embodiment.
The embodiment of the present invention provides a kind of sound equipment with usb 1 01, refers to Fig. 2, and sound equipment comprises usb 1 01, audio interface 102, audio processing chip 103, audio frequency power amplifier chip 104 and loud speaker 105;
The data input pin of audio processing chip 103 is connected usb 1 01 with voltage input end, the control end of audio processing chip 103 connects audio interface 102, the data output end of audio processing chip 103 connects the digital audio signal input of audio frequency power amplifier chip 104, the voltage input end of audio frequency power amplifier chip 104 connects usb 1 01, the simulated audio signal input of audio frequency power amplifier chip 104 is connected audio interface 102 with control end, and the output of audio frequency power amplifier chip 104 connects loud speaker 105;
When usb 1 01 is connected with external equipment, the voltage exported by external equipment is that audio processing chip 103 and audio frequency power amplifier chip 104 are powered, and the voice data that external equipment exports is sent to audio processing chip 103;
The first control signal is generated when audio interface 102 is in vacant state, first control signal is sent to audio processing chip 103 and audio frequency power amplifier chip 104 by audio interface 102, audio processing chip 103 converts voice data to digital audio and video signals according to the first control signal, and digital audio and video signals is sent to audio frequency power amplifier chip 104, audio frequency power amplifier chip 104 is sent to loud speaker 105 after digital audio and video signals being carried out amplification and digital-to-analogue conversion according to the first control signal;
The second control signal is generated when audio interface 102 accessing to audio plug, second control signal is sent to audio processing chip 103 and audio frequency power amplifier chip 104 by audio interface 102, and the simulated audio signal that external equipment sends is sent to audio frequency power amplifier chip 104, audio processing chip 103 is in off state according to the second control signal, and audio frequency power amplifier chip 104 is sent to loud speaker 105 after being amplified by simulated audio signal.
The present invention uses the audio chip supporting USB input as the audio processing chip 103 of sound equipment, audio frequency power amplifier is used to drive loud speaker 105, when the usb 1 01 of USB sound equipment is connected to external equipment, such as computer, computer identifies audio processing chip 103 automatically, and automatic load driver, be configured to the audio frequency apparatus that can play, just can automatically switch this equipment audio output apparatus by default, and after this, the sound play on computers is just sent by this USB sound equipment.
When connecting usb 1 01, if when connecting tone frequency channel wire again to the audio interface 102 of USB sound equipment, computer identification before the audio frequency apparatus used disconnect automatically, and are switched to audio output apparatus work.Sound equipment operating state is now: use USB line to power, and by audio interface 102 signal input part by default, and amplify audio signal to loud speaker 105.
Optionally, as shown in Figure 3, audio frequency power amplifier chip 104 comprises analog signal amplifier 1041, digital signal amplifier 1043, digital to analog converter 1044 and driver 1042;
The input of analog signal amplifier 1041 is the simulated audio signal input of audio frequency power amplifier chip 104, the output of analog signal amplifier 1041 connects the first input end of driver 1042, the input of digital signal amplifier 1043 is the digital audio signal input of audio frequency power amplifier chip 104, the input of the output linking number weighted-voltage D/A converter 1044 of digital signal amplifier 1043, the output of digital to analog converter 1044 connects the second input of driver 1042, and the output of driver 1042 is the output of audio frequency power amplifier chip 104.
Analog signal amplifier 1041 exports to driver 1042 after being amplified by simulated audio signal, digital signal amplifier 1043 exports to digital to analog converter 1044 after being amplified by digital audio and video signals, and digital to analog converter 1044 sends to driver 1042 after converting digital audio and video signals to simulated audio signal.
Optionally, as shown in Figure 4, audio interface 102 comprises earth terminal A, the first signal end B, secondary signal end C and the 3rd signal end D;
When audio interface 102 accessing to audio plug 110, ground wire a, earth terminal A and the first signal end B of audio jack 110 are interconnected, and are low level second control signal to generate level.
Optionally, audio interface 102 also comprises pull-up circuit, and pull-up circuit is connected with the first signal end B;
When audio interface 102 is in vacant state, pull-up circuit generates the second control signal that level is high level.
In the present invention, the interface of USB sound equipment outside is 3.5mm stereo audio interface 102 and usb 1 01, uses stereo audio line to be connected with USB line.USB line must be inserted, to provide the power supply needed for work during sound equipment work.
The control signal that audio interface 102 produces determines the working method of sound equipment, when control signal is high level, audio processing chip 103 is in running order, the mode being converted into digital audio with the data of compunlcation outputs to audio frequency power amplifier chip 104, audio frequency power amplifier chip 104 can support digital-to-analog two kinds of audio frequency input modes, when control signal is 1, the input mode of audio frequency power amplifier chip 104 is digital audio and video signals input, and digital audio and video signals input is amplified through decoding, DAC conversion exports loudspeaker to.
When control signal is 0, audio processing chip 103 is in closed condition, and computer detection is less than this audio frequency apparatus, and the acquiescence output equipment of computer end naturally can be switched to analogue audio frequency and export.The input mode of audio frequency power amplifier chip 104 is switched to analog input, directly amplifies the simulated audio signal from computer or other equipment.
Control signal, while shutoff audio processing chip 103, makes audio frequency power amplifier chip 104 be switched to analog input.And while opening audio processing chip 103, audio frequency power amplifier chip 104 is switched to digital audio and video signals input, enable sound equipment switch operating state at any time.Employ four end audio interface 102 at the audio input port of USB sound equipment, and tone frequency channel wire uses common stereo audio line.Four end audio frequency are widely used in mobile phone, are characterized in using same 3.5mm interface, and are divided into two by the GND of stereo audio interface 102 end, are mainly used to connect microphone.This design can use four end audio sockets in USB sound equipment, when inserting stereo audio interface 102, A, B end then on socket can link together, and B end is owing to producing control signal, A end is ground, then formation control signal is the state of 0, and USB sound equipment is operated in the mode of analogue audio frequency input.When extracting tone frequency channel wire, the connection between A and B disconnects, and control signal is in vacant state, and when there being pull-up circuit, then control signal is high level, and USB sound equipment is operated in the mode of USB input.
The present invention also provides a kind of based on the above-mentioned control method with the sound equipment of usb 1 01, and as shown in Figure 5 and Figure 6, control method comprises the following steps:
The voltage that external equipment exports, when usb 1 01 is connected with external equipment, is used for powering to audio processing chip 103 and audio frequency power amplifier chip 104 by step S201., and the voice data that external equipment exports is sent to audio processing chip 103.
Step S202. is when audio interface 102 is in vacant state, and audio interface 102 generates the first control signal, and the first control signal is sent to audio processing chip 103 and audio frequency power amplifier chip 104.
Step S203. audio processing chip 103 converts voice data to digital audio and video signals according to the first control signal, and digital audio and video signals is sent to audio frequency power amplifier chip 104;
Step S204. audio frequency power amplifier chip 104 is sent to loud speaker 105 after digital audio and video signals being carried out amplification and digital-to-analogue conversion according to the first control signal;
Step S205. is when audio interface 102 accessing to audio plug, audio interface 102 generates the second control signal, second control signal is sent to audio processing chip 103 and audio frequency power amplifier chip 104, and the simulated audio signal that external equipment sends is sent to audio frequency power amplifier chip 104;
Step S206. audio processing chip 103 is in off state according to the second control signal;
Loud speaker 105 is sent to after simulated audio signal amplifies by step S207. audio frequency power amplifier chip 104.
Optionally, audio interface 102 comprises earth terminal, the first signal end, secondary signal end and the 3rd signal end;
The step generating the second control signal during audio interface 102 accessing to audio plug is specially:
The ground wire of audio jack, earth terminal and the first signal end are interconnected, and are low level second control signal to generate level.
Optionally, audio interface 102 also comprises pull-up circuit, and pull-up circuit is connected with the first signal end;
Audio interface 102 generates the first control signal step when being in vacant state is specially:
Pull-up circuit generates the second control signal that level is high level.
A kind of sound equipment and control method thereof with USB interface provided by the invention, according to the control signal that audio interface sends, both can choice for use USB as the connected mode of input signal, support plug and play under windows system; Also can select USB as power supply simultaneously, use tone frequency channel wire as input, use as traditional sound equipment, a tone frequency channel wire can be saved when connecting computer USB interface, user-friendly, can realize high-quality transmission tonequality, lossless audio transmits, simplify the operation of user simultaneously, and reduce the requirement to audio frequency output performances such as computers.
Above content is in conjunction with concrete preferred implementation further description made for the present invention, can not assert that specific embodiment of the invention is confined to these explanations.For general technical staff of the technical field of the invention; make some equivalent alternative or obvious modification without departing from the inventive concept of the premise; and performance or purposes identical, all should be considered as belonging to the scope of patent protection that the present invention is determined by submitted to claims.
Claims (7)
1. have a sound equipment for USB interface, it is characterized in that, described sound equipment comprises USB interface, audio interface, audio processing chip, audio frequency power amplifier chip and loud speaker;
The data input pin of described audio processing chip is connected described USB interface with voltage input end, the control end of described audio processing chip connects described audio interface, the data output end of described audio processing chip connects the digital audio signal input of described audio frequency power amplifier chip, the voltage input end of described audio frequency power amplifier chip connects described USB interface, the simulated audio signal input of described audio frequency power amplifier chip is connected described audio interface with control end, and the output of described audio frequency power amplifier chip connects described loud speaker;
When described USB interface is connected with external equipment, the voltage that described external equipment is exported is described audio processing chip and described audio frequency power amplifier chip power supply, and the voice data that described external equipment exports is sent to described audio processing chip;
When described audio interface is in vacant state, described audio interface generates the first control signal, and described first control signal is sent to described audio processing chip and described audio frequency power amplifier chip, described audio processing chip converts described voice data to digital audio and video signals according to described first control signal, and described digital audio and video signals is sent to described audio frequency power amplifier chip, described audio frequency power amplifier chip is sent to described loud speaker after described digital audio and video signals being carried out amplification and digital-to-analogue conversion according to described first control signal;
When described audio interface accessing to audio plug, described audio interface generates the second control signal, and described second control signal is sent to described audio processing chip and described audio frequency power amplifier chip, and the simulated audio signal that described external equipment sends is sent to described audio frequency power amplifier chip, described audio processing chip is in off state according to described second control signal, and described audio frequency power amplifier chip is sent to described loud speaker after being amplified by described simulated audio signal according to described second control signal.
2. sound equipment as claimed in claim 1, it is characterized in that, described audio frequency power amplifier chip comprises analog signal amplifier, digital signal amplifier, digital to analog converter and driver;
The input of described analog signal amplifier is the simulated audio signal input of described audio frequency power amplifier chip, the output of described analog signal amplifier connects the first input end of described driver, the input of described digital signal amplifier is the digital audio signal input of described audio frequency power amplifier chip, the output of described digital signal amplifier connects the input of described digital to analog converter, the output of described digital to analog converter connects the second input of described driver, and the output of described driver is the output of described audio frequency power amplifier chip.
3. sound equipment as claimed in claim 2, it is characterized in that, described audio interface comprises earth terminal, the first signal end, secondary signal end and the 3rd signal end;
When described audio interface accessing to audio plug, the ground wire of described audio jack and described earth terminal and described first signal end are interconnected, and are low level second control signal to generate level.
4. sound equipment as claimed in claim 3, it is characterized in that: described audio interface also comprises pull-up circuit, described pull-up circuit is connected with described first signal end;
When described audio interface is in vacant state, described pull-up circuit generates the second control signal that level is high level.
5. a control method with the sound equipment of USB interface according to claim 1, is characterized in that, described control method comprises the following steps:
When described USB interface is connected with external equipment, the voltage exported by described external equipment is described audio processing chip and described audio frequency power amplifier chip power supply, and the voice data that described external equipment exports is sent to described audio processing chip;
When described audio interface is in vacant state, described audio interface generates the first control signal, and described first control signal is sent to described audio processing chip and described audio frequency power amplifier chip;
Described audio processing chip converts described voice data to digital audio and video signals according to described first control signal, and described digital audio and video signals is sent to described audio frequency power amplifier chip;
Described audio frequency power amplifier chip is sent to described loud speaker after described digital audio and video signals being carried out amplification and digital-to-analogue conversion according to described first control signal;
When described audio interface accessing to audio plug, described audio interface generates the second control signal, described second control signal is sent to described audio processing chip and described audio frequency power amplifier chip, and the simulated audio signal that described external equipment sends is sent to described audio frequency power amplifier chip;
Described audio processing chip is in off state according to described second control signal;
Described audio frequency power amplifier chip is sent to described loud speaker after being amplified by described simulated audio signal.
6. control method as claimed in claim 5, is characterized in that: described audio interface comprises earth terminal, the first signal end, secondary signal end and the 3rd signal end;
The step generating the second control signal during described audio interface accessing to audio plug is specially:
The ground wire of described audio jack and described earth terminal and described first signal end are interconnected, and are low level second control signal to generate level.
7. control method as claimed in claim 6, it is characterized in that: described audio interface also comprises pull-up circuit, described pull-up circuit is connected with described first signal end;
Described audio interface generates the first control signal step when being in vacant state is specially:
Described pull-up circuit generates the second control signal that level is high level.
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201510018384.4A CN104581505A (en) | 2015-01-14 | 2015-01-14 | Sound box with USB interface and control method of sound box |
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| Application Number | Priority Date | Filing Date | Title |
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| CN201510018384.4A CN104581505A (en) | 2015-01-14 | 2015-01-14 | Sound box with USB interface and control method of sound box |
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| CN201510018384.4A Pending CN104581505A (en) | 2015-01-14 | 2015-01-14 | Sound box with USB interface and control method of sound box |
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Cited By (2)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106331927A (en) * | 2016-09-09 | 2017-01-11 | 歌尔科技有限公司 | Audio equipment |
| CN109655735A (en) * | 2018-12-07 | 2019-04-19 | 武汉市聚芯微电子有限责任公司 | Power amplifier chips evaluation board and power amplifier chips evaluation board system |
-
2015
- 2015-01-14 CN CN201510018384.4A patent/CN104581505A/en active Pending
Cited By (3)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN106331927A (en) * | 2016-09-09 | 2017-01-11 | 歌尔科技有限公司 | Audio equipment |
| CN109655735A (en) * | 2018-12-07 | 2019-04-19 | 武汉市聚芯微电子有限责任公司 | Power amplifier chips evaluation board and power amplifier chips evaluation board system |
| CN109655735B (en) * | 2018-12-07 | 2021-07-13 | 武汉市聚芯微电子有限责任公司 | Power amplifier chip evaluation board and power amplifier chip evaluation board system |
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