CN115714951A - Multichannel audio frequency coupling device, intelligent lock and door - Google Patents
Multichannel audio frequency coupling device, intelligent lock and door Download PDFInfo
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- CN115714951A CN115714951A CN202211439646.0A CN202211439646A CN115714951A CN 115714951 A CN115714951 A CN 115714951A CN 202211439646 A CN202211439646 A CN 202211439646A CN 115714951 A CN115714951 A CN 115714951A
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Abstract
The invention provides a multi-channel audio coupling device, an intelligent lock and a door, wherein the multi-channel audio coupling device comprises: the audio signal access modules are used for accessing audio signals; the input end of the coupling circuit module is connected with the output ends of the plurality of audio signal access modules and is used for coupling the accessed multi-channel audio signals into one-channel coupling audio signal and outputting the coupled audio signal; and the input end of the audio power amplifier module is connected with the output end of the coupling circuit module and is used for carrying out power amplification processing on the received coupled audio signal. The invention can solve the technical problems that a plurality of loudspeakers are arranged in the lock in the prior art, the cost is increased, the structure needs to be specially designed, the space is extremely occupied, and the structural complexity and the appearance simplicity are seriously influenced.
Description
Technical Field
The embodiment of the invention relates to the technical field of electronic circuits, in particular to a multi-channel audio coupling device, an intelligent lock and a door.
Background
The function integration of intelligence lock is more and more, by original simple function of unblanking, gradually with security protection monitoring function, the function is talkbacked in pronunciation, AI speech recognition intelligence talkbacks etc. and all modules are independent each other. As a manufacturer of the smart lock, it may not be good at the production of each function module and the development of the internal function implementation algorithm. At present, a common practice is to find manufacturers in corresponding fields to customize corresponding functional modules and then integrate the functional modules. Probably a plurality of functional module all can need play sound this moment, lead to the tool to lock to embed to have a plurality of speakers, the cost increase, structurally still need do special design for each speaker moreover, extremely occupation space seriously influences the succinct of structure complexity and outward appearance.
Disclosure of Invention
The application provides a multichannel audio frequency coupling device, intelligent lock and door, has built-in a plurality of speakers of tool to lock among the solution prior art, and the cost-push still needs to do special design for each speaker structurally moreover, and extremely occupation space seriously influences the technical problem of the succinct nature of structure complexity and outward appearance.
The first aspect of the present invention provides a multi-channel audio coupling device, comprising: the audio signal access modules are used for accessing audio signals; the input end of the coupling circuit module is connected with the output ends of the plurality of audio signal access modules and is used for coupling the accessed multi-channel audio signals into one-channel coupling audio signal and outputting the coupled audio signal; and the input end of the audio power amplification module is connected with the output end of the coupling circuit module and is used for performing power amplification processing on the received coupled audio signal.
The multi-channel audio coupling device provided by the embodiment of the invention has the advantages that the multi-channel audio signals are synthesized into one coupling audio signal to be output, so that the cost is obviously reduced, and the complexity of the structural design is obviously reduced.
Optionally, the method further comprises: the input end of the enabling circuit module is connected with the output ends of the audio signal access modules, and the output end of the enabling circuit module is connected with the enabling end of the audio power amplifier module and used for controlling the audio power amplifier module to respond to power amplification processing of the received coupled audio signals when any audio signal is accessed.
Optionally, a coupling circuit module, comprising: each filter circuit is used for denoising the input audio signal; and the input end of the coupling circuit is connected with the output end of each filter circuit and is used for coupling the audio signals subjected to denoising processing by each filter circuit into a coupling audio signal and outputting the coupling audio signal.
Optionally, the coupling circuit module further includes: and the voltage reduction circuit is arranged at the front end of the coupling circuit and is used for carrying out voltage reduction processing on each path of input audio signal.
Optionally, the voltage reduction circuit is a bidirectional voltage reduction circuit; the filter circuit is a band-pass filter circuit or a low-pass filter circuit.
Optionally, the coupling circuit module further includes: and each isolating circuit is arranged between the filter circuit and the coupling circuit and is used for isolating the input circuits of the audio signals from each other.
Optionally, the circuit module is enabled, comprising: the first OR logic circuit is used for carrying out OR logic operation processing on the enable signal accompanied with each path of input audio signal.
Optionally, the enabling circuit module comprises: a detection circuit for detecting whether an audio signal is input; the input end of the delay circuit is connected with the output end of the detection circuit and is used for keeping the signal detected by the detection circuit for a preset time length; and the input end of the second OR logic circuit is connected with the output end of the delay circuit and is used for carrying out OR logic operation processing on the enable signal accompanied with the input audio signal and the signal output by the delay circuit.
A second aspect of the present invention provides an intelligent lock, including: the first aspect, or the multiple audio coupling apparatus provided in any optional embodiment of the first aspect; and the input end of the loudspeaker is connected with the output end of the audio power amplification module of the multi-channel audio coupling device and is used for playing the coupled audio signals output by the multi-channel audio coupling device.
A third aspect of the invention provides a door comprising: the second aspect provides an intelligent lock.
Drawings
In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the embodiments or the prior art will be briefly described below, and it is obvious that the drawings in the following description are some embodiments of the present invention, and other drawings can be obtained by those skilled in the art without creative efforts.
Fig. 1 is a schematic structural diagram of a multi-channel audio coupling device according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a multi-channel audio coupling device according to an embodiment of the present invention;
fig. 3 is a schematic structural diagram of a multi-channel audio coupling device according to an embodiment of the present invention;
fig. 4 is a schematic structural diagram of a multi-channel audio coupling device according to an embodiment of the present invention;
fig. 5 is a schematic structural diagram of a multi-channel audio coupling device according to an embodiment of the present invention;
fig. 6 is a schematic structural diagram of a multi-channel audio coupling device according to an embodiment of the present invention;
fig. 7 is a schematic structural diagram of a multi-channel audio coupling device according to an embodiment of the present invention;
fig. 8 is a schematic structural diagram of an intelligent lock according to an embodiment of the present invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the embodiments of the present disclosure more apparent, the technical solutions of the embodiments of the present disclosure will be described clearly and completely with reference to the drawings of the embodiments of the present disclosure. It is to be understood that the described embodiments are only a few embodiments of the present disclosure, and not all embodiments. All other embodiments, which can be derived by a person skilled in the art from the described embodiments of the disclosure without any inventive step, are within the scope of protection of the disclosure.
Unless otherwise defined, technical or scientific terms used herein shall have the ordinary meaning as understood by one of ordinary skill in the art to which this disclosure belongs. The use of "a," "an," or "the" and similar words in this disclosure also does not imply a limitation on the number, but rather the presence of at least one. The word "comprising" or "comprises", and the like, means that the element or item preceding the word comprises the element or item listed after the word and its equivalent, but does not exclude other elements or items.
In addition, the technical features involved in the different embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other.
In view of the technical problems mentioned in the background, an embodiment of the present invention provides a multi-channel audio coupling apparatus, as shown in fig. 1, the apparatus including:
and the audio signal access modules are used for accessing audio signals.
Illustratively, the accessed audio signal is generated by a corresponding module with a voice prompt function, such as prompt tones for prompting the user that the fingerprint verification fails, the unlocking succeeds and the like, which are sent by the fingerprint verification module. Specifically, the module with the voice prompt function may include, but is not limited to, a security monitoring module with the voice prompt function, a voice intercom module, an AI voice recognition module, and the like. Each audio signal access module corresponds to a module with a voice prompt function. As shown in fig. 1, includes a plurality of audio signal access modules: the audio signal access module 1, the audio signal access module 2, and the … … audio signal access module N are each configured to access one channel of audio signal.
And the input end of the coupling circuit module is connected with the output ends of the plurality of audio signal access modules and is used for coupling the accessed multi-channel audio signals into one-channel coupled audio signal and outputting the coupled audio signal. The embodiment of the present application does not limit the specific circuit composition inside the coupling circuit module, and those skilled in the art can determine the specific circuit composition according to actual needs as long as the coupling of multiple audio signals can be achieved.
And the input end of the audio power amplifier module is connected with the output end of the coupling circuit module and is used for carrying out power amplification processing on the received coupled audio signal.
Illustratively, the audio power amplifier module includes an audio power amplifier, which amplifies the smaller audio signal to increase its power and then outputs the amplified audio signal to push the speaker to sound, thereby reproducing the sound. The embodiment of the application does not limit the specific circuit composition inside the audio power amplification module, and a person skilled in the art can determine according to actual needs as long as the audio signal power amplification can be realized.
The multi-channel audio coupling device provided by the embodiment of the invention has the advantages that the multi-channel audio signals are synthesized into one coupling audio signal to be output, so that the cost is obviously reduced, and the complexity of the structural design is obviously reduced.
As shown in fig. 2, as an alternative embodiment of the present invention, the present invention further includes:
the input end of the enabling circuit module is connected with the output ends of the audio signal access modules, and the output end of the enabling circuit module is connected with the enabling end of the audio power amplifier module and used for controlling the audio power amplifier module to respond to power amplification processing of the received coupled audio signals when any audio signal is accessed.
Illustratively, the enabling circuit module may control an operating state of the audio power amplifier module. Specifically, when a voice signal is input, the enabling circuit module raises the enabling end of the audio power amplification module, so that the audio power amplification module performs power amplification processing on the accessed audio signal; when no audio signal is input, the enabling circuit module can enable the enabling end of the audio power amplification module to be in a pull-down state or a turn-off state, and at the moment, the audio power amplification module is in a low power consumption state or a no power consumption state. The specific circuit composition inside the audio power amplifier module is not limited in the embodiment of the application, and a person skilled in the art can determine the specific circuit composition according to actual needs as long as the corresponding enabling control function can be realized.
The multi-channel audio coupling device provided by the embodiment of the invention controls the working state of the audio power amplification module through the enabling circuit module, avoids the problem of invalid power consumption caused by the consumption of energy by quiescent current in a circuit when the audio power amplification module is in the working state all the time even if no audio signal is input, and achieves the purposes of saving energy and prolonging the service life of the audio power amplification module.
As shown in fig. 3, as an alternative embodiment of the present invention, a coupling circuit module includes:
and each filter circuit is used for denoising the input audio signal.
Illustratively, the noise includes a modulated signal and a non-audio interference signal in the modulated audio signal. The module with voice prompt function comprises a power amplifier module, outputs modulated audio signals, such as a class D power amplifier, and modulates the audio signals by using PWM (pulse width modulation), wherein the frequency of the PWM is higher, generally in the order of hundreds of kHz, and the modulated signals of the type are filtered; meanwhile, the coupling circuit module may access some external non-audio interference signals while accessing the audio signal input by the audio signal access module.
And the input end of the coupling circuit is connected with the output end of each filter circuit and is used for coupling the audio signals subjected to denoising processing by each filter circuit into a coupling audio signal and outputting the coupling audio signal.
Illustratively, the function of the coupling circuit is to synthesize the multiple audio signals subjected to denoising processing by the filter circuit into one path. The coupling mode includes, but is not limited to, using capacitive coupling to superpose and output two or more signals after dc is cut off.
According to the multi-channel audio coupling device provided by the embodiment of the invention, the noise removal processing is carried out on the audio signal through the filter circuit, the influence of the noise of the circuit and the environmental noise on the device is avoided, and the noise immunity of the device is improved; meanwhile, the interference signal in the audio signal is reduced, and the quality of the audio signal is improved.
As shown in fig. 4, as an optional embodiment of the present invention, the coupling circuit module further includes:
and the voltage reduction circuit is arranged at the front end of the coupling circuit and is used for carrying out voltage reduction processing on each path of input audio signal.
Illustratively, the voltage reduction circuit can be arranged before the filtering current and directly receive the audio signal accessed by the audio signal access module; or the filter circuit can be arranged behind the filter circuit, and the audio signal subjected to the denoising processing by the filter circuit is subjected to voltage reduction processing and then input into the coupling circuit. The position of the voltage reduction circuit in each input branch is not limited herein. As an alternative embodiment, the voltage reduction circuit may take the form of a voltage divider.
The multi-channel audio coupling device provided by the embodiment of the invention performs voltage reduction processing on input audio signals with different driving voltages by arranging the voltage reduction circuit, and converts the audio signals into output voltage suitable for processing of the audio power amplification module, so that the audio power amplification module serving as a load can work normally.
As an optional embodiment of the present invention, the step-down circuit is a bidirectional step-down circuit.
Illustratively, the buck module may implement bi-directional buck, as shown in fig. 4. Specifically, if the audio signal access module 1 has a signal input, but the audio signal access module 2 does not have a signal input at this time, a signal of the audio signal access module 1 passes through each circuit module on the first input branch, and then flows back to the audio signal access module 2 through the coupling circuit, the filter circuit 2 and the voltage reduction circuit 2 during coupling, and if the energy of the flowing back is too high, the front-end circuit is damaged. Therefore, the voltage reduction module not only needs to be capable of reducing the voltage of the audio signal turning right from left, but also needs to be capable of reducing the voltage of the signal turning left from right, the voltage of reverse irrigation is guaranteed to be small enough, and the safety of the front-end circuit of the circuit module is protected.
The filter circuit is a band-pass filter circuit or a low-pass filter circuit.
Illustratively, the filtering circuit in this embodiment employs band-pass filtering, or low-pass filtering. The class of filters includes, but is not limited to, the use of second order low pass filters. The filtering range of the filter circuit can be set in a preset range, such as the average hearing range of human ears, but is not limited thereto, for example, 20kHz is the highest value of human ears, but is not limited to 20kHz, since the frequency of human voice is far lower than this, and can be adjusted adaptively, and is not limited herein. As an alternative, the filter circuit may employ RC filtering.
The band-pass filter circuit or the low-pass filter circuit is adopted to perform denoising processing on the audio signal, so that the selection difficulty of the filter circuit is reduced, the filtering is more targeted, and the filtering efficiency and quality are effectively improved.
As shown in fig. 5, as an alternative embodiment of the present invention, the coupling circuit module further includes:
and each isolating circuit is arranged between the filter circuit and the coupling circuit and is used for isolating the input circuits of the audio signals from each other.
Illustratively, there are many isolation methods such as a relay isolation method, a photocoupler isolation method, a direct current voltage isolation method, a linear isolation amplifier isolation method, an a/D converter isolation method, and the like. The types of the isolation circuits are many, the design is relatively mature, and the isolation circuits can be adaptively selected according to the actual application requirements, which is not described herein again.
According to the multi-channel audio coupling device provided by the embodiment of the invention, the isolation circuit is adopted among the input branches, so that the voltage among the input branches is prevented from flowing backwards, and the safety and reliability of the circuit are improved; and the noise crosstalk between the input branches is cut off, so that the effect of inhibiting the noise interference between the input branches is achieved, and the quality of the audio signal is improved.
As shown in fig. 6, as an alternative embodiment of the present invention, an enable circuit module includes:
the first OR logic circuit is used for carrying out OR logic operation processing on the enable signal accompanied with each path of input audio signal.
Illustratively, when an input audio signal is accompanied by an output enable signal, the first or logic circuit receives all enable signals and performs or logic operation, when at least one enable signal exists, the first or logic circuit outputs high level to pull up the enable end of the audio power amplification module, and the audio power amplification module responds to the received coupled audio signal and performs power amplification processing; when no input audio signal exists, namely no enable signal exists, the first OR logic circuit outputs low level to pull down or turn off the enable end of the audio power amplification module, and the audio power amplification module does not work.
The multi-channel audio coupling device provided by the embodiment of the invention controls the working state of the audio power amplification module through the first or logic circuit, avoids the problem of invalid power consumption caused by the consumption of static current to energy in the circuit because the audio power amplification module is still in the working state even if no audio signal is input, and achieves the purposes of saving energy and prolonging the service life of the audio power amplification module.
As shown in fig. 7, as an alternative embodiment of the present invention, an enable circuit module includes:
and the detection circuit is used for detecting whether an audio signal is input.
And the input end of the delay circuit is connected with the output end of the detection circuit and is used for keeping the signal detected by the detection circuit for a preset time length.
And the input end of the second OR logic circuit is connected with the output end of the delay circuit and is used for carrying out OR logic operation processing on an enable signal accompanied by the input audio signal and a signal output by the delay circuit.
Illustratively, not all input audio signals are accompanied by the output enable signal, the detection circuit is used for detecting the audio signal access end, once the audio signal input is detected, the detection circuit is triggered, after the triggering, the signal detected by the detection circuit is kept through the delay circuit, or the preset time period T is delayed, and after the time period T is delayed, the level is recovered. The second OR logic circuit performs OR logic operation processing on an enabling signal accompanied by the input audio signal and a signal output by the delay circuit, when at least one audio signal is input, the second OR logic circuit outputs a high level to pull up an enabling end of the audio power amplification module, and the audio power amplification module responds to the received coupled audio signal and amplifies the power of the received coupled audio signal; when the audio signal is not input, namely the enable signal is not input, the second or logic circuit outputs low level to pull down or switch off the enable end of the audio power amplification module, and the audio power amplification module does not work. Specifically, taking the preset time duration T =1s as an example, as long as the audio signal access module 2 has a signal input, the delay circuit generates a high level lasting for 1s, and the level continues until the audio signal access module 2 has no signal input and then keeps 1s to end. The other input branches are the same in structure and are not described in detail.
The multi-channel audio coupling device provided by the embodiment of the invention is provided with the detection circuit to detect the audio signal without the enabling signal, so as to realize the control of the audio power amplification module. The time delay circuit keeps the signal that detection circuit detected predetermineeing for a long time, avoids because audio signal's discontinuity, perhaps volatility, and the high-low level signal that detection circuit detected that causes frequently changes, and then the problem to the control failure of audio power amplifier module.
As shown in fig. 8, an embodiment of the present invention provides an intelligent lock, including:
any of the above embodiments provides a multi-channel audio coupling device.
This embodiment is similar to the above embodiment, and is not described herein again.
And the input end of the loudspeaker is connected with the output end of the audio power amplification module of the multi-channel audio coupling device and is used for playing the coupled audio signals output by the multi-channel audio coupling device.
According to the intelligent lock provided by the embodiment of the invention, the number of the loudspeakers is reduced to one by the multi-channel audio coupling device, so that the cost is obviously reduced, the complexity of design is simplified, the space is saved, and the simplicity of appearance is increased.
An embodiment of the present invention provides a door, including:
the intelligence lock that any embodiment provided above.
This embodiment is similar to the description of the corresponding parts of the above embodiments, and is not repeated here.
According to the door provided by the embodiment of the invention, the intelligent lock provided by any embodiment is used, so that the cost is obviously reduced.
In the description herein, reference to the description of the terms "this embodiment," "one embodiment," "some embodiments," "an example," "a specific example," or "some examples," etc., means that a particular feature, structure, material, or characteristic described in connection with the embodiment or example is included in at least one embodiment or example of the present disclosure. In this specification, the schematic representations of the terms used above are not necessarily intended to refer to the same embodiment or example. Furthermore, the particular features, structures, materials, or characteristics described may be combined in any suitable manner in any one or more embodiments or examples. Furthermore, various embodiments or examples and features of different embodiments or examples described in this specification can be combined and combined by one skilled in the art without contradiction. In the description of the present disclosure, "a plurality" means at least two, e.g., two, three, etc., unless explicitly specifically limited otherwise.
It should be understood that the above examples are only for clarity of illustration and are not intended to limit the embodiments. Other variations and modifications will be apparent to persons skilled in the art in light of the above description. And are neither required nor exhaustive of all embodiments. And obvious variations or modifications of the invention may be made without departing from the spirit or scope of the invention.
Claims (10)
1. A multi-channel audio coupling device, comprising:
the audio signal access modules are used for accessing audio signals;
the input end of the coupling circuit module is connected with the output ends of the audio signal access modules and is used for coupling the accessed multiple paths of audio signals into one path of coupled audio signal and outputting the coupled audio signal;
and the input end of the audio power amplifier module is connected with the output end of the coupling circuit module and is used for performing power amplification processing on the received coupled audio signal.
2. The multi-channel audio coupling device of claim 1, further comprising:
the input end of the enabling circuit module is connected with the output ends of the audio signal access modules, and the output end of the enabling circuit module is connected with the enabling end of the audio power amplifier module and used for controlling the audio power amplifier module to respond to power amplification processing of the received coupled audio signals when any audio signal is accessed.
3. The multi-channel audio coupling device of claim 1, wherein the coupling circuit module comprises:
each filter circuit is used for denoising the input audio signal;
and the input end of the coupling circuit is connected with the output end of each filter circuit and is used for coupling the audio signals subjected to denoising processing by each filter circuit into a coupling audio signal and outputting the coupling audio signal.
4. The multi-channel audio coupling device of claim 3, wherein the coupling circuit module further comprises:
and the voltage reduction circuit is arranged at the front end of the coupling circuit and is used for carrying out voltage reduction processing on each path of input audio signal.
5. The multi-channel audio coupling device of claim 4,
the voltage reduction circuit is a bidirectional voltage reduction circuit;
the filter circuit is a band-pass filter circuit or a low-pass filter circuit.
6. The multi-channel audio coupling device of claim 3, wherein the coupling circuit module further comprises:
and each isolating circuit is arranged between the filter circuit and the coupling circuit and is used for isolating the input circuits of the audio signals from each other.
7. The multi-channel audio coupling device of claim 2, wherein the enabling circuit module comprises:
the first OR logic circuit is used for carrying out OR logic operation processing on the enable signal accompanied with each path of input audio signal.
8. The multi-channel audio coupling device of claim 2, wherein the enabling circuit module comprises:
a detection circuit for detecting whether an audio signal is input;
the input end of the delay circuit is connected with the output end of the detection circuit and is used for keeping the signal detected by the detection circuit for a preset time length;
and the input end of the second OR logic circuit is connected with the output end of the delay circuit and is used for carrying out OR logic operation processing on an enable signal accompanied by the input audio signal and a signal output by the delay circuit.
9. An intelligent lock, comprising:
the multi-channel audio coupling device of any one of claims 1-8;
and the input end of the loudspeaker is connected with the output end of the audio power amplification module of the multi-channel audio coupling device and is used for playing the coupled audio signals output by the multi-channel audio coupling device.
10. A door, comprising:
the smart lock of claim 9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211439646.0A CN115714951A (en) | 2022-11-17 | 2022-11-17 | Multichannel audio frequency coupling device, intelligent lock and door |
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| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202211439646.0A CN115714951A (en) | 2022-11-17 | 2022-11-17 | Multichannel audio frequency coupling device, intelligent lock and door |
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| CN115714951A true CN115714951A (en) | 2023-02-24 |
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| CN202211439646.0A Pending CN115714951A (en) | 2022-11-17 | 2022-11-17 | Multichannel audio frequency coupling device, intelligent lock and door |
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| CN (1) | CN115714951A (en) |
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