CN110440914B - Noise reduction system for photoelectric detection and AOI detection equipment - Google Patents
Noise reduction system for photoelectric detection and AOI detection equipment Download PDFInfo
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Abstract
The invention discloses a noise reduction system for photoelectric detection and AOI detection equipment, wherein the system comprises a first PCB structure and a second PCB structure, the first PCB structure comprises an optical signal acquisition module and an analog-to-digital conversion module which are integrated on a first PCB circuit board, and the second PCB structure comprises a digital signal processing module which is integrated on a second PCB circuit board; the optical signal acquisition module is integrated in the first area of the first PCB circuit board, the analog-to-digital conversion module is electrically connected with the digital signal processing module, and the consistency of the acquisition channel and the consistency of the board card of the whole noise reduction system are improved through the specific structure arrangement, so that the noise of the whole noise reduction system is reduced, and the measurement accuracy of the noise reduction system is improved.
Description
Technical Field
The invention belongs to the field of photoelectric detection, and particularly relates to a noise reduction system and AOI detection equipment for photoelectric detection.
Background
The photoelectric detection system is a system for collecting optical signals and converting the optical signals into corresponding electric signals by utilizing a photoelectric effect to perform detection, and particularly, the photoelectric effect refers to a phenomenon that when light irradiates on certain substances, electrons of the substances absorb energy of photons to generate corresponding electric effect. Photoelectric effects are classified into three categories according to their phenomena: external photoelectric effect, internal photoelectric effect and photovoltaic effect. The photoelectric devices comprise a photoelectric tube, a photomultiplier, a photoresistor, a photosensitive diode, a photosensitive triode, a photoelectric cell and the like.
Since the electrical signal converted from the optical signal is an analog signal, the analog signal needs to be converted into a digital signal, and the process of converting the analog signal into the digital signal is called analog-to-digital conversion (a/D conversion for short), and the a/D conversion is used to convert an analog quantity with continuous time and continuous amplitude into a digital signal with discrete time and discrete amplitude, so the a/D conversion generally needs 4 processes of sampling, holding, quantizing and encoding. In practical circuits, some of these processes are combined, for example, sampling and holding, quantization and coding are often implemented simultaneously in the conversion process.
At present, analog-to-digital conversion can be realized by using an analog-to-digital conversion chip (ADC chip), specifically, the ADC chip is a chip that converts an analog signal collected by an internal quantization processing circuit into a digital signal suitable for storage, and how to reduce system noise of a photoelectric detection system and improve accuracy of a sampled signal in a signal collection process of the whole photoelectric detection system is an important problem in the industry.
Disclosure of Invention
In view of the above defects or improvement requirements of the prior art, the noise reduction system and the AOI detection device for photoelectric detection provided by the present invention isolate the analog circuit part and the digital part of the whole noise reduction system by setting the first PCB structure and the second PCB structure, and improve the consistency of the acquisition channel and the consistency of the board card of the whole noise reduction system by integrating the optical signal acquisition module in the first region of the first PCB circuit board by the above specific structural setting, thereby reducing the noise of the whole noise reduction system, and improving the measurement accuracy of the noise reduction system.
To achieve the above object, according to one aspect of the present invention, there is provided a noise reduction system for photodetection, the system including a first PCB structure and a second PCB structure, the first PCB structure including an optical signal acquisition module and an analog-to-digital conversion module integrated on a first PCB circuit board, the second PCB structure including a digital signal processing module integrated on a second PCB circuit board; the optical signal acquisition module is integrated in a first area of the first PCB, and the analog-to-digital conversion module is connected with the digital signal processing module through a wire.
As a further improvement of the invention, the first area is welded with the first shielding cover, and the welding area of the first shielding cover is electrically connected with the GND area of the first PCB circuit board.
As a further improvement of the present invention, the noise reduction system further includes a second shielding cover and a structural member, the second shielding cover and the structural member form a hollow cavity, the hollow cavity is used for accommodating the first PCB structure and the second PCB structure, and the second shielding cover is electrically connected to the GND area of the first PCB circuit board.
As a further improvement of the present invention, the first PCB structure further includes an analog power supply circuit integrated with the first PCB circuit board, and the GND area of the first PCB circuit board includes a first GND area for grounding of a control signal of the analog power supply circuit and a second GND area for grounding of a power supply signal of the analog power supply circuit.
As a further improvement of the present invention, the first PCB structure includes a reference circuit and an analog power circuit integrated on the first PCB circuit board, the reference circuit is used for providing a reference voltage, the analog power circuit is used for providing a power supply for the optical signal acquisition module and the analog-to-digital conversion module, and a signal return path of the reference circuit and a signal return path of the analog power circuit do not pass through the first area.
As a further improvement of the present invention, the optical signal acquisition module comprises one or more photodiodes.
As a further improvement of the present invention, the wiring of the first region is used only for the pin wiring of the photodiode.
As a further improvement of the invention, a leakage current protection ring is arranged at the position of the photodiode corresponding to the pin of the first PCB.
As a further improvement of the invention, the second PCB structure comprises a USB module integrated on the second PCB circuit board, and the USB module is also used for providing a system power supply of the noise reduction system.
To achieve the above object, according to another aspect of the present invention, there is provided an AOI detection apparatus including the above noise reduction system for photodetection.
Generally, compared with the prior art, the above technical solution conceived by the present invention has the following beneficial effects:
according to the noise reduction system and the AOI detection device for photoelectric detection, the first PCB structure and the second PCB structure are arranged to isolate the analog circuit part and the digital part of the whole noise reduction system, the optical signal acquisition module is integrated in the first area of the first PCB, the consistency of the acquisition channel and the consistency of the board card of the whole noise reduction system are improved through the specific structural arrangement, the noise of the whole noise reduction system is reduced, and the measurement accuracy of the noise reduction system is improved.
According to the noise reduction system and the AOI detection equipment for photoelectric detection, disclosed by the invention, the influence of external noise elimination internal switch noise on the optical signal acquisition module is further isolated by arranging the convex first shielding cover in the first area, and meanwhile, the influence of external radiation noise on the first PCB structure is eliminated by utilizing the second shielding cover.
According to the noise reduction system and the AOI detection device for photoelectric detection, the first GND area for grounding the control signal of the analog power supply circuit and the power supply signal for grounding the analog power supply circuit are arranged, and the control signal of the analog power supply circuit and the power supply signal are grounded separately, so that ground bounce suppression can be realized, accurate control of the control circuit of the analog power supply on the output voltage of the control circuit can be provided, the output power supply noise of the analog power supply circuit is further reduced, the precision of the output power supply of the analog power supply circuit is improved, and the measurement accuracy of the noise reduction system is further improved.
According to the noise reduction system and the AOI detection equipment for photoelectric detection, disclosed by the invention, the signal return path of the reference circuit and the signal return path of the analog power supply circuit do not pass through the first region (sensitive region) in the diagram, so that the influence of differential mode noise is avoided, and the measurement accuracy of the noise reduction system is further improved.
According to the noise reduction system and the AOI detection equipment for photoelectric detection, the leakage current protection ring is arranged at the PCB pin of the photodiode for photoelectric detection, so that the impedance between the input of the collected signal and the ground can be reduced, and the measurement accuracy of the whole noise reduction system is prevented from being influenced by the leakage current.
Drawings
Fig. 1 is a schematic structural diagram of a noise reduction system for photoelectric detection according to an embodiment of the present invention;
fig. 2 is a schematic structural diagram of a GND area of a first PCB board according to an embodiment of the present invention;
FIG. 3 is a schematic diagram of a return path according to an embodiment of the invention.
Detailed Description
In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is described in further detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.
In addition, the technical features involved in the embodiments of the present invention described below may be combined with each other as long as they do not conflict with each other. The present invention will be described in further detail with reference to specific embodiments.
In the process of collecting the photoelectric detection signal, the strength of the collected photoelectric detection signal may be very weak, especially in the AOI detection field, the collected image signal (such as brightness) may be an extremely weak analog signal, and the low-brightness output current is only pA level. The applicant finds that, in this case, if the structure of the noise reduction system for photodetection is not reasonable, then the weak analog signal may have external radiation noise, internal switch noise, on-board power supply noise, common mode noise, differential mode noise coupled between the analog signal and the GND copper strap, distributed capacitance of the photodiode, and noise caused by leakage current, and meanwhile, various noises may have the effect of mutual interference, and the noise is likely to submerge the output weak analog current, resulting in large fluctuation of the photodetection data, and thus very poor repeatability and consistency of the device test, and not little influence on the accuracy of the photodetection signal sampling.
In view of the above drawbacks or needs for improvement, the applicant proposes a noise reduction system for photodetection, the system comprising a first PCB structure and a second PCB structure, the first PCB structure comprising an optical signal acquisition module and an analog-to-digital conversion module integrated in a first PCB circuit board, wherein the optical signal acquisition module is integrated in a first area of the first PCB circuit board, and the second PCB structure comprising a digital signal processing module integrated in a second PCB circuit board; the optical signal acquisition module is electrically connected with the analog-to-digital conversion module, and the analog-to-digital conversion module is connected with the digital signal processing module through a wire; the optical signal acquisition module is used for acquiring an optical signal of an object to be detected and converting the optical signal into an analog sampling signal; the analog-to-digital conversion module is used for converting the analog sampling signal into a digital sampling signal; the digital signal processing module is used for processing digital sampling signals according to preset instructions, and through the specific structure arrangement, the consistency of the acquisition channel and the consistency of the board card of the whole noise reduction system are improved, the noise of the whole noise reduction system is reduced, and therefore the measurement accuracy of the noise reduction system is improved.
Fig. 1 is a schematic structural diagram of a noise reduction system for photoelectric detection according to an embodiment of the present invention. As an example, the first PCB structure in the figure is composed of a first PCB circuit board, an optical signal acquisition module and an analog-to-digital conversion module, the second PCB structure is composed of a digital signal processing module integrated in a second PCB circuit board, the optical signal acquisition module is integrated in a first area of the analog board, the size of the first area can be correspondingly set according to the size of the optical signal acquisition module, the specific position of the first area on the analog board can be correspondingly adjusted according to the arrangement requirement of the whole system circuit, the optical signal acquisition module is electrically connected with the analog-to-digital conversion module, the analog-to-digital conversion module is electrically connected with the digital signal processing module, as an example, the optical signal acquisition module and the analog-to-digital conversion module can be electrically connected by using PCB wiring in the first PCB circuit board, the analog-to-digital conversion module and the digital signal processing module can be electrically connected by using the interconnection mode between chips such as FPC wiring or FFC wiring, the analog-to-digital conversion module and the digital signal processing module can also be connected by using a motor connecting wire, and the connection mode can be adjusted according to the wiring requirement.
As a preferable scheme, a first shielding cover (small shielding cover) is welded in the first area, the welding area of the first area is electrically connected with the first PCB circuit board, namely, the GND area on the analog board, because the internal switching noise is caused by the digital circuit part, the photoelectric acquisition module is shielded by the first shielding cover, and the influence caused by the internal switching noise can be eliminated by connecting the first shielding cover with the ground on the analog board.
Furthermore, the noise reduction system further comprises a second shielding cover (a large shielding cover) and a structural member, wherein the second shielding cover and the structural member form a hollow cavity, the hollow cavity is used for accommodating the first PCB structure and the second PCB structure, and the second shielding cover is electrically connected with the GND area of the first PCB circuit board.
Fig. 2 is a schematic structural diagram of a GND area of the first PCB in the embodiment of the present invention. As shown in fig. 2, the first PCB structure further includes an analog power circuit, the GND area of the first PCB circuit board includes a first GND area and a second GND area, the first GND area is used for grounding the control signal of the analog power circuit, the second GND area is used for grounding the power signal of the analog power circuit, and by separating the control signal of the analog power circuit from the power signal grounding mode, ground bounce suppression can be achieved, so that accurate control of the control circuit of the analog power to the output voltage of the analog power circuit can be provided, the output power noise of the analog power circuit is further reduced, the precision of the output power of the analog power circuit is improved, and the measurement accuracy of the noise reduction system is further improved.
FIG. 3 is a schematic diagram of a return path according to an embodiment of the invention. As shown in fig. 3, the first PCB structure includes a reference circuit for providing a reference voltage and an analog power circuit for providing a power supply for the optical signal collection module and the analog-to-digital conversion module, and a signal return path of the reference circuit and a signal return path of the analog power circuit do not pass through the first area. Generally, differential mode noise is caused by voltage difference fluctuation between common mode signals, ideally, the common mode signal and the common mode noise are equal in potential at an input point, and there should be no voltage difference between the common mode signal and the common mode noise, but actually, this is not the case, because the return current on the ground plane is relatively complex, the potentials at different points on the ground plane are different, and the potential fluctuation of each point is variable; the return path comprises a signal return path and a power supply return path, and it can be understood that any point potential on the ground plane is the result of potential superposition caused by the return, and because the flow direction and the size of the return are relatively complex, the potential analysis on the ground plane is relatively complex.
For sensitive signal input, in order to avoid differential mode noise caused by a complex ground plane, backflow exists objectively, the backflow is guided to a ground plane area which is insensitive to the backflow, and for sensitive input signals, the ground plane area of the backflow is not doped with irrelevant backflow as much as possible, so that the differential mode noise is eliminated. If the current is not drained, the backflow path always flows to a reference point of the ground plane along a path with the minimum impedance, and if the sensitive area falls on a path which is necessary for backflow, the fluctuation of the ground plane of the sensitive area can be caused; therefore, the signal return path of the reference circuit and the signal return path of the analog power supply circuit shown in fig. 3 do not pass through the first region (sensitive region) in the figure, so that the influence of differential mode noise can be well avoided, and the measurement accuracy of the noise reduction system can be further improved.
As a preferred embodiment, the photoelectric collecting module can be implemented by combining one or more photodiodes, and as a further preferred, the wiring of the first area of the first PCB circuit board is only used for the pin wiring of the photodiode, and through the wiring process, the distance between the collected signal of the photodiode and the ground can be pulled apart, thereby reducing the distributed capacitance.
Furthermore, the photodiode is provided with a leakage current protection ring corresponding to the pin of the first PCB. The reason for generating the leakage current is that the input resistance of the photodiode operational amplifier is too large and exceeds the insulation resistance of the FR4 of the PCB, so that part of current can flow to another acquisition channel to form current leakage, the leakage is captured by the protection ring and cannot pollute the other acquisition channel, the leakage current protection ring is connected to the ground, so that low impedance is formed between the input of multi-channel acquisition signals and the ground, and the leakage current only leaks to the ground and cannot leak to other acquisition channels through the PCB.
As a preferred scheme, the second PCB structure further includes a USB module, and certainly can also supply power through other dc power supplies or ac power supplies, and can be adjusted accordingly according to application requirements, optionally, the USB module is used for external human-computer interaction, and the USB module is also used for providing a power supply of the whole noise reduction system, further, the USB module is provided with a corresponding isolation measure to reduce common mode noise, and specifically, an external power supply inlet of the USB module can be isolated through an antistatic device, a voltage stabilizing circuit, and an isolation power supply; isolating an output signal path of the USB module through a common mode choke coil and a signal isolator; and the isolation belt of the USB module is connected across a corresponding resistor to provide a corresponding discharge path for the static electricity in the USB circuit. After the isolation measure is taken, the impedance between the common-mode noise input point and the ground after the isolation is obviously smaller than the impedance between the common-mode noise input point and the ground before the isolation, so that the noise of the ground reference point can be controlled through the isolation, and the reliability of the whole system is improved.
As an example, the above noise reduction system for photodetection can be used to realize single small signal acquisition and processing with high precision (e.g. 200ppm) requirement, wherein since there is no leakage from adjacent channel in single output, and therefore the influence of distributed capacitance is not considered, the following scheme can be adopted: the first PCB structure consists of a first PCB circuit board, an optical signal acquisition module, a reference circuit, an analog power circuit and an analog-digital conversion module, the second PCB structure consists of a digital signal processing module integrated on the second PCB circuit board, the optical signal acquisition module is integrated in a first area of the analog board, a welding area of the first area is electrically connected with a GND area of the first PCB circuit board, a hollow part formed by a shielding case and a structural member is used for accommodating the first PCB structure and the second PCB structure, and the second shielding case is electrically connected with the GND area of the first PCB circuit board; the GND area of the first PCB circuit board comprises a first GND area and a second GND area, the first GND area is used for grounding a control signal of the analog power supply circuit, and the second GND area is used for grounding a power supply signal of the analog power supply circuit; the signal backflow path of the reference circuit and the signal backflow path of the analog power circuit do not pass through the first area, further, the system can selectively utilize the USB module of the second PCB structure to supply power, and corresponding isolation parts are designed for the USB module according to requirements to reduce common mode noise, so that the whole noise of the whole system for acquiring small signals in a single path is reduced, and the requirement of acquiring the small signals in the single path with high precision is met; of course, the above noise reduction scheme can be adjusted accordingly according to the noise reduction requirement of the actual circuit.
The noise reduction system provided by the embodiment of the application provides an environmental noise system analysis scheme, and the limitation of a single noise reduction measure can be effectively avoided through a scientific method of comprehensively controlling the source and accurately butting the measures, the effectiveness of noise reduction design is improved, and the noise reduction system can be widely applied to the field of high-precision detection equipment. In addition, the noise reduction system can eliminate the influence of various environmental noise sources one by one through scientific analysis of the environmental noise sources, so that the system noise approaches to the device noise, the expected target of low noise is achieved, various noise sources can be eliminated without omission through the system, the purpose of noise reduction is effectively achieved, the consistency of the acquisition channel of the noise reduction system and the consistency of the board card are improved, and the noise reduction system is suitable for batch production. Meanwhile, the noise reduction system scheme of the embodiment of the application is suitable for mass production of the precision detection equipment, and can meet the mass production requirement of the precision detection equipment.
Furthermore, the noise reduction system for photoelectric detection can be used for realizing multi-path small signal acquisition and processing with high precision (such as 200ppm) requirements, because leakage of adjacent channel channels exists in multi-path output, the influence of distributed capacitance needs to be considered, therefore, wiring of a first area can be only used for wiring of a photodiode on the basis of the noise reduction system for single-channel signals, and an isolation protection ring is arranged at a pin of the photodiode, so that the overall noise of the whole system for multi-path acquired small signals is reduced, and the requirement of multi-path high-precision small signal acquisition is met; of course, the above noise reduction scheme can be adjusted accordingly according to the noise reduction requirement of the actual circuit.
As a preferable scheme, the noise reduction system for photodetection can be used to implement noise reduction processing for low-frequency noise in the system, and preferably, the GND area of the first PCB circuit board includes a first GND area and a second GND area, the first GND area is used for grounding of the control signal of the analog power supply circuit, and the second GND area is used for grounding of the power supply signal of the analog power supply circuit; the signal return path of the reference circuit and the signal return path of the analog power supply circuit do not pass through the first area; the measures are adopted to reduce the influence of differential mode noise and power supply noise on the whole system, furthermore, for the condition of multi-channel input signals, a leakage current protection ring can be preferably arranged at a pin of the photodiode to reduce the noise generated by distributed capacitance, and meanwhile, when the USB module is powered by the power supply, the USB module can be preferably arranged with an isolation component to reduce common mode noise.
As a preferable scheme, the noise reduction system for photoelectric detection can be used for realizing noise reduction processing on high-frequency noise existing in the system, and a first shielding cover, a second shielding cover and a structural member are preferably adopted; the GND area of the first PCB circuit board comprises a first GND area and a second GND area, the first GND area is used for grounding a control signal of the analog power supply circuit, and the second GND area is used for grounding a power supply signal of the analog power supply circuit; the signal return path of the reference circuit and the signal return path of the analog power supply circuit do not pass through the first area; the measures are adopted to reduce the influence of external radiation noise, internal switch noise, differential mode noise and power supply noise on the whole system, furthermore, for the condition of multi-channel input signals, the wiring of the first area can be preferably used for the wiring of the photodiode, a leakage current protection ring is arranged at the pin of the photodiode to reduce the noise generated by distributed capacitance and leakage current, meanwhile, when the USB module is used for power supply, the USB module can be preferably adopted to be provided with an isolation component to reduce common mode noise, and certainly, the noise reduction scheme can be correspondingly adjusted according to the noise reduction requirement of an actual circuit.
The noise reduction system provided by the embodiment of the application provides an environmental noise system analysis scheme, and the limitation of a single noise reduction measure can be effectively avoided through a scientific method of comprehensively controlling the source and accurately butting the measures, the effectiveness of noise reduction design is improved, and the noise reduction system can be widely applied to the field of high-precision detection equipment. In addition, the noise reduction system can eliminate the influence of various environmental noise sources one by one through analyzing the environmental noise sources, so that the system noise approaches to the device noise, the expected target of low noise is achieved, various noise sources can be eliminated without omission through the system, the purpose of noise reduction is effectively achieved, the consistency of the acquisition channel of the noise reduction system and the consistency of the board card are improved, and the noise reduction system is suitable for batch production. Meanwhile, the noise reduction system scheme of the embodiment of the application is suitable for mass production of the precision detection equipment, and can meet the mass production requirement of the precision detection equipment.
As an example, in an application field of an AOI detection apparatus, signal acquisition and noise reduction processing may be performed using the above system. Of course, those skilled in the art will readily appreciate that the above described system is merely a preferred embodiment, and other devices for signal acquisition and noise reduction using the above described system are all within the scope of the present invention.
It will be understood by those skilled in the art that the foregoing is only a preferred embodiment of the present invention, and is not intended to limit the invention, and that any modification, equivalent replacement, or improvement made within the spirit and principle of the present invention should be included in the scope of the present invention.
Claims (10)
1. A noise reduction system for photoelectric detection is characterized by comprising a first PCB structure and a second PCB structure, wherein the first PCB structure comprises an optical signal acquisition module and an analog-to-digital conversion module which are integrated on a first PCB circuit board, and the second PCB structure comprises a digital signal processing module which is integrated on a second PCB circuit board; the optical signal acquisition module is integrated in a first area of the first PCB, and the analog-to-digital conversion module is connected with the digital signal processing module through a wire;
the first PCB structure comprises a reference circuit and an analog power circuit, the reference circuit is integrated with the first PCB circuit board and used for providing reference voltage, the analog power circuit is used for providing power for the optical signal acquisition module and the analog-to-digital conversion module, and a signal backflow path of the reference circuit and a signal backflow path of the analog power circuit do not pass through the first area.
2. The noise reduction system for photodetection according to claim 1, characterized in that, the first region is soldered with a first shield can, and the soldering region of the first shield can is electrically connected with the GND region of the first PCB circuit board.
3. The noise reduction system for photodetection according to claim 1, characterized in that, the noise reduction system further comprises a second shielding cover and a structural member, the second shielding cover and the structural member form a hollow cavity, the hollow cavity is used for accommodating the first PCB structure and the second PCB structure, and the second shielding cover is electrically connected with the GND area of the first PCB circuit board.
4. The noise reduction system for photodetection according to claim 1, characterized in that the first PCB structure further comprises an analog power supply circuit integrated to the first PCB wiring board, the GND region of the first PCB wiring board comprises a first GND region for control signal ground of the analog power supply circuit and a second GND region for power supply signal ground of the analog power supply circuit.
5. The noise reduction system for photodetection according to claim 1, characterized in that the optical signal acquisition module comprises one or more photodiodes.
6. The noise reduction system for photodetection according to claim 5, characterized in that the wiring of the first region is only used for the pin wiring of the photodiode.
7. The noise reduction system for photodetection according to claim 5, characterized in that, the photodiode is provided with a leakage current protection ring corresponding to the pin of the first PCB circuit board.
8. A noise reduction system for photodetection according to any of the claims 1-7 is characterized in that the second PCB structure comprises a USB module integrated to the second PCB wiring board, the USB module being used to provide the system power supply of the noise reduction system.
9. The noise reduction system for photodetection according to claim 8, characterized in that the USB module is provided with an isolation component to reduce common mode noise.
10. An AOI detection apparatus comprising a noise reduction system for photodetection according to any of claims 1-9.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201910621189.9A CN110440914B (en) | 2019-07-10 | 2019-07-10 | Noise reduction system for photoelectric detection and AOI detection equipment |
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| CN205754239U (en) * | 2016-05-24 | 2016-11-30 | 深圳市赛盛技术股份有限公司 | A kind of circuit solving USB device interference wireless device |
| CN207570667U (en) * | 2017-09-07 | 2018-07-03 | 中兴通讯股份有限公司 | The detection device and equipment of luminous power |
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| CN205754239U (en) * | 2016-05-24 | 2016-11-30 | 深圳市赛盛技术股份有限公司 | A kind of circuit solving USB device interference wireless device |
| CN207570667U (en) * | 2017-09-07 | 2018-07-03 | 中兴通讯股份有限公司 | The detection device and equipment of luminous power |
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