Posts Tagged ‘printed circuit board’

Do you know the relationship between copper thickness and circuit width & spacing?

Saturday, September 2nd, 2023

We know the precision control and performance of a product are paramount, only know that PCB can be built with a nice function, so, to understand the intricate relationship between copper thickness and circuit width and spacing is pivotal. These two parameters are like the gears of a well-oiled machine, interlocking in ways that significantly influence the printed circuit board‘s functionality, signal integrity, and manufacturability. If the designer does not consider the relationship between these two, the design may need to be modified in subsequent production.

In order to avoiding this information, let’s embark on a deeper exploration of this dynamic relationship to uncover its nuances and implications now,

Frist of all, we need to know some basic information about PCB, like copper thickness, circuit width and spacing.

  1. The Essence of Copper Thickness

Copper, known for its exceptional electrical conductivity, is the lifeblood of any PCB. The copper thickness refers to the amount of copper deposited onto the board’s surface during fabrication. It’s the foundation upon which the traces, the intricate pathways that carry electrical signals, are built. The standard copper thickness is often measured in ounces per square foot (oz/ft²) or micrometers (µm). Common options include 1oz (35µm), 2oz (70µm), and even higher, it depends on customer’s requirement.

  • Circuit Width and Spacing

Circuit width and spacing, though often overlooked, are integral components that determine a PCB’s performance, integrity, and overall functionality. Circuit width refers to the dimension of the conductive traces, while spacing pertains to the distance between these traces. These seemingly simple dimensions have a profound impact on the PCB’s behavior.

Secondly, Unveiling the Intricate Relationship

The relationship between copper thickness, circuit width, and spacing is a sophisticated interplay of electrical properties, heat dissipation, and signal integrity. Let’s delve deeper into this complex web of interactions:

Current-Carrying Capacity and Copper Thickness: Copper thickness directly influences a trace’s ability to carry current without succumbing to overheating. Thicker copper translates to higher current-carrying capacity and reduced resistive losses. However, the trade-off is that wider traces are necessary to accommodate the increased copper thickness.

Resistance and Circuit Width: Wider traces exhibit lower resistance, which in turn reduces voltage drop and enhances the efficiency of signal transmission. Designers must strike a balance between trace width, copper thickness, and available board space.

Spacing and Unwanted Interactions: As circuit spacing decreases, the probability of unwanted interactions, such as crosstalk and electromagnetic interference, rises. Thicker copper can exacerbate these issues due to its larger cross-sectional area. Maintaining appropriate spacing between traces is pivotal to prevent signal degradation and maintain integrity.

Heat Dissipation and Trace Width: Thicker copper also aids in better heat dissipation, a crucial consideration for power-intensive applications. However, this can necessitate wider traces to manage the thermal load effectively.

Signal Integrity and Crosstalk: Smaller spacing reduces the risk of crosstalk, but it’s a double-edged sword. Thicker copper traces may introduce higher capacitance, altering impedance and potentially impacting signal integrity. This delicate balance requires careful consideration during design.

For now, we have known the relationship between them, how to develop a best design between the circuit width & spacing and copper thickness, which depends on what’s you really want, the huge current or heat management? Following details should be considered if you want to develop the best circuit width & spacing.

Current Requirements: Start by understanding the current requirements of your traces based on the components and operational conditions. Selecting the appropriate copper thickness and trace width ensures the PCB can handle the anticipated loads.

Thermal Management: Thicker copper facilitates heat dissipation, which is advantageous for power-dissipating components. However, remember that it might necessitate wider traces to ensure effective heat transfer.

Manufacturability: While thicker copper can enhance current-carrying capacity and heat dissipation, it might pose manufacturing challenges. Consult with PCB manufacturers to align your design choices with their capabilities.

Signal Integrity Analysis: Utilize simulation tools to analyze signal integrity, especially when dealing with smaller spacing and thicker copper. These tools provide insights into impedance matching, potential crosstalk, and overall performance.

Flexibility VS Rigidity: While thicker copper enhances many aspects, it can impact the PCB’s flexibility, crucial for certain applications. Evaluate the mechanical demands of your project and strike the right balance.

Regarding metal core PCB in Best Technology, the copper thickness and its accordingly circuit width & spacing like below, furthermore, it would be better if you can let me know your copper thickness before checking your drawing, we will give you the best solution before formal production.

Copper thicknessMinimum circuit widthMinimum circuit spacing
0.5-2oz0.25mm0.23mm
3oz0.35mm0.3mm
4oz0.4mm0.38mm
(trace_design_guide_of_MCPCB)

Conclusion: Striking the Optimal Balance

The intricate relationship between copper thickness, circuit width, and spacing in PCB design embodies a delicate equilibrium that significantly influences a design’s performance and functionality. This nuanced interplay directly impacts parameters such as current-carrying capacity, resistance, heat dissipation, and signal integrity.

Achieving the optimal balance between these factors requires a deep understanding of electrical properties, thermal considerations, and signal behavior. Designers must carefully evaluate the specific requirements of their projects and leverage simulation tools to fine-tune their choices. Collaboration with PCB manufacturers ensures alignment with manufacturing capabilities.

The dynamic nature of this relationship underscores the constant evolution of PCB technology. As devices become smaller, faster, and more interconnected, the demand for intricate layouts intensifies. Designers must continuously adapt to new challenges, pushing the boundaries of what’s achievable while adhering to the fundamental principles that govern PCB design.

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The Difference Between 2L MCPCB and Double Sided MCPCB

Monday, February 27th, 2023

In our last article, we know what a metal core PCB is, in this post, we will introduce what is the difference between 2L MCPCB and Double sided MCPCB. Please continue to read if you want to know more about metal core printed circuit board.

Today we will explain from these four contents as following:

  1. Stack up (structure)
  2. Heat dissipation
  3. SMD populate
  4. Manufacturing technology

Stack up of 2L MCPCB and Double Sided MCPCB

For a 2L MCPCB, the metal core is positioning on the bottom side of the MCPCB as a cooling carrier to the whole MCPCB, while the metal base of double sided MCPCB is located in the middle of two copper trace. In generally, some PTH (plated-through-hole) vias are needed to designed to connect the bottom and top traces.

Below are the stack ups of these two kinds of products, from the structure, we can easily distinguish which one is 2L MCPCB and which one is double sided MCPCB.

Heat dissipation of 2L MCPCB and Double Sided MCPCB

Due to the different structure of the two products, their heat dissipation performance is also different. The main reason is the heating of double-sided metal core circuits can be spread out through both top and bottom side, while the heating generate by SMD components of 2 layers circuit only can be dissipated through bottom (metal) side and the heat need to go down layer by layer. In addition to this, the dissipation of FR4 is not good than metal materials, so double-sided metal core printed circuits perform better heat dissipation performance than 2 layers MCPCB.

Surface mounted locations (SMD populate)

Nowadays, surface mounted technology (SMT) is widely used in printed circuit board industry, more and more designers prefer to populate electronic components of the circuit surface to achieve high density, stable electrical performance and high reliability. 2L metal core circuit boards and double-sided metal core circuits also show their different mounted locations in this aspect.

The populate location of a 2L MCPCB only available on copper trace side, that is top side. And a double-sided metal core PCB can mount components on both top and bottom side, because both of them exist copper trace on it.

Manufacturing technology

May somebody will curious about “Are these two products produced in the same process/technology?”

The answer is obvious “NO, they have a different laminate process when fabricating.”

Different with single layer MCPCB, double sided MCPCB requires an additional pressing step to laminate the thermal conductive layer and metal core together. But sometimes, some raw Metal Clad material vendor will supply board material which already laminated.

For 2 layers metal core PCB, due to it is made of a single MCPCB and a double-sided FR4 PCB, the first thing we should make a double sided FR4 PCB, then laminate the PCB together with the single MCPCB. But due to the thermal conductive layer (pure adhesive) is easy to overflow during laminating process, which will cause the poor adhesion and crack between metal core and FR4 PCB. In the meantime, to avoid such problem, an experienced operator is needed to proceed the laminated process. That is why the lead time and cost of a 2 layers metal core circuit is much longer and expensive.

This is the end of this post, if you still have some questions or difficulties about the metal core PCB, welcome to contact us at sales@bestpcbs.com, our professional sales team and engineering team will give you a best solution for free.

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Differences Between Solder Mask and Solder Paste in PCB

Wednesday, December 7th, 2022

When it comes to solder mask and solder paste, there are some engineers confused about their functionalities and even most of laymen thought they are the same, this is not hypothetical, it is real that happened to me. So today let’s explain differences between Solder Mask and Solder Paste for you.

Part 1: What is Solder Mask?

If you had ever seen a printed circuit board, you may see there is a layer of green ink cover on the PCB surface while some orange-yellow areas didn’t cover by ink. In PCB industry, the green ink we called Solder Mask, or abbreviated as S/M, and exposed area is copper, they were leave as GND plane or soldering pads to mount electronic components.

Solder mask is a liquid acrylic oligomer, which has variety of colors such as red, blue, green, white, black. Green is commonly used in the process of PCB manufacturing, so some professional engineers call it as green oil.

Solder_mask

Solder mask applied on the PCB designed as a protection layer to avoid oxidation, corrosion and other environmental impacts when they leave production line. In addition, solder mask between solder pads also can help to prevent forming to solder bridge when assembly.

Below are some other functions of coating a layer solder mask:

  • Prevent physical line breaking of copper trace
  • Only weld in the area that must be soldered to avoid waste of soldering
  • Reduce copper pollution to soldering groove 
  • Prevent insulation deterioration and corrosion caused by dust, moisture and other external environmental factors 
  • With high insulation, so that the high-density circuit is possible

Part 2: What is Solder Paste?

Solder Paste also known as “Solder cream”, is a most important soldering material used in surface mount technology (SMT) process. Mainly function for soldering resistors, capacitors, ICs and other electronic components onto the PCB surface to form a permanent connection.

The solder particles are a mixture of solder formed by mixing solder powder, flux and other surfactants and thixotropic. Traditionally this used to be tin and lead, but with the legislation has been introduced around the world, to only use lead free solders. These may be made from a variety of mixtures, Best Technology commonly used is SAC305 which includes 96.5% tin, 0.5% copper and 3.0% silver, some manufacturers also use 99.7% tin and 0.3% copper, whereas there are other mixtures that include other metals including tin.

Due to the role of solder paste in assembly, solder paste storage is extremely important. However, solder paste got into drying during storing became a common problem faced by most PCBA manufacturers, so How to solve solder paste dry problem is premier.

Solder_paste

Part 3: The Difference Between Solder Mask and Solder Paste

  1. Solder mask is a formal part of PCB, but solder paste ONLY for PCB assembly.
  2. Solder mask is not allowed on the solder pads while solder paste can be printed on the solder pads openings.
  3. Solder mask is used for applying solder mask ink, but solder paste is used for applying paste.
  4. Solder mask has many available colors, but paste mask visually gray.
  5. Solder mask is coating during PCB fabrication, but solder paste is printing when PCB assembly.

With over 16 years in PCB industry, Best Technology is one of the most reliable PCB and PCBA supplier in Asia, we commit to provide high quality products with excellent service before and after sales, to take care our customers wholeheartedly, and to treat customers’ business as ours. At the same time, we keep learning and continually to improve ourselves so that we can catch up the latest technology trend and provide better and better service for our customers.

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X-ray Inspection in PCB Assembly

Wednesday, June 15th, 2022

X-Ray Inspection’s Definition

X-ray inspection is a technology used to inspect the hidden features of the target objects or products. As for PCB inspection, X-ray is commonly used in the inspection of PCB assembly in order to test the quality and find the hidden defects, X-ray inspection is one of the most important steps for quality-oriented PCB manufacturers.

X-Ray Machine

X-Ray Inspection’s Working Principle

Generally, there are three elements in the X-ray devices.

  • X-ray tube—to generate the X-ray photons.
  • Operation platform—to move along with the sample so that the sample can be inspected from different angles and magnification.
  • Detector—it can capture the X-ray through the samples and then transfer it into the image so that we can find out whether there are defects on the printed circuit board.

The Hidden Defects that can be Identified by X-Ray

Since PCB has the higher density with the solder joints hidden and holes buried or blind, X-ray enable us to inspect the quality of the PCB and identify various hidden defects. And there are three common hidden defects that can be inspected by X-ray.

PCB’s Image Under X-Ray
  • Solder bridges—it is a common issue that will occur when the solder joints are so close that they create a connection which is not allowed. And usually, the solder bridges will be covered by some components on the PCB. But they can be easily found with the help of the X-ray device.
  • Solder voids—when gas or flux is entrained during welding, solder voids will be produced, which will lower the thermal conductivity at the solder joint and may cause physical defects. And X-ray can help to  identify the solder voids
  • Pin-hole fills—pin-hole fills issue is a common problem occurring in the plug-in components on the  printed circuit boards. The X-ray device can be used to identify these errors, and can even quantify the missing filling amount.

Our X-Ray Inspection Device

The maximum size of the board that can be put in the device’s operation platform is 510*430 mm, while the maximum inspection size of the device is 435*385 mm. So here is the manifestation of the operation platform’s function. When the size of PCB is over 435*385 mm, the operation platform will move along with the board so that the board can be inspected thoroughly.

And here is a video about operation of our X-ray inspection device.

So, this is the end of this article. In case if you have any questions, you are welcome to contact us via email at  sales@bestpcbs.com. We are fully equipped to handle your PCB  manufacturing requirements.

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3M Epoxy Adhesive DP190-Gray & 3M Epoxy Adhesive DP190-Translucent

Friday, April 22nd, 2022

Both 3M Epoxy Adhesive DP190-Gray and 3M Epoxy Adhesive DP190-Translucent are a two-part epoxy adhesive that delivers exceptional performance with high shear and peel strength.

They can bond to a wide range of materials, such as metals, ceramics, wood, fiberboard, glass, rubber and many plastics. So, PCB is no exception. But what are the similarities and differences between them?

Similarities

  • Provide tough, strong bonds through high shear and peel strength.
  • Capable of bonding to a wide variety of different materials.
  • Deliver extended work-life, providing additional time for adjustment.
  • Exhibit good environmental aging properties, delivering long-term durability.

Differences

3M Epoxy Adhesive DP190-Gray has a moderately high modulus. With a 90-minute work-life, it reaches handling strength in approximately 10 hours and full cure in 7 days at room temperature.

Additionally, this epoxy adhesive has medium viscosity and self-leveling with a 1:1 mix ratio by volume. But its flexibility and elongation are moderate.

(3M Epoxy Adhesive DP190-Gray)

3M Epoxy Adhesive DP190-Translucent has a moderately low modulus. With an 80-minute work-life, it reaches handling strength in approximately 10 hours and full cure in 14 days at room temperature.

It has low viscosity and self-leveling with a 1:1 mix ratio by volume. Additionally, it features high flexibility and elongation.

3M Epoxy Adhesive DP190–Translucent

This is all about the similarities and differences between the 3M Epoxy Adhesive DP190-Gray and 3M Epoxy Adhesive DP190-Translucent. It is supposed that you have known about them.

But if you still have any questions about them or PCB, please feel free to contact us. Because at Best Technology, we are fully equipped to handle your PCB manufacturing requirements.

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Can you tell the difference between PWB and PCB?

Wednesday, May 20th, 2020

The abbreviations PWB and PCB are very common, especially in the field of electronics manufacturing. Therefore it is necessary to gain a clear understanding of the meaning of each one and the differences between the two. On this article, we will help our readers to distinguish PWB from PCB.

pcb vs pwb
pcb vs pwb

 PCB: Based on insulating substrate, it means a kind of products on which the wires are connected and components are printed from point to point on a dielectric substrate in a predetermined design. It is the English abbreviation of Printed Circuit Board.In a word, PCB stands for printed circuit board, where the width, side to side and multi-layer relationship(spacing) of conductor runs has or is designed to have a specific effect on circuit operation other than just a point to point connection.

 PWB: Based on insulating substrate, it means a kind of products on which the wires are connected from point to point on a dielectric substrate in a predetermined design. However, there is no printed component on it. PWBs are the early name of the British, because at that time there were only circuit diagrams on the circuit board, but no printed components. So they belonged to the more primitive board. Under its effect, now many traditional British and some Hong Kong people still call the circuit board to be PWB, which is the English abbreviation of Printed Wire Board. In a word, PWB stands for printed wiring board, one of the first uses when the issue was only a point to point connection.

The PCBs are the boards already equipped with various components, however the PWB is just a designed substrate with no components.

pcb vs pwb
pcb vs pwb

Moreover, PWB vs PCB greatly varies from one region to the other. For example, in the United States of America, the term Printed Circuit Board is more common in use while the use of the name PWB is more commonly used in Japan. In Japan, PWB is more preferred that PCB because it prevents confusion with another name, polychlorinated biphenyls, which refers to a particular poison available in Japan.

For your more information, in approximately 1999 the IPC Technical Activities Executive Committee made a mandate to only use the term PCB for all new document development because more often than not the printed circuitry design will have an impact on function.

If you are still confused or have any queries or comments about PCB, do not hesitate to contact us. Our sales team can give you a reply at our soonest convenience.

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The Harms and Solutions of Fingerprint on PCB

Wednesday, January 23rd, 2019

The fingerprint is one of the major disasters of PCB and it will also cause the poor products of PCB as well as deterioration of terminal user reliability. However, the manual operation will go through every step of printed circuit board manufacturing. Only every operator forms a good habit and stop touch the PCB with bare-hands, so that can reduce the fingerprint doing the harms to PCBs. As the professional PCB vendor, BEST would like to let you know more details of the harms and provide some solutions for you.

Do not Touch the PCB with bare hands

Do not Touch the PCB with bare hands

The Harms of Fingerprint on PCB
A. If the bare-hands touch the printed circuit board directly, it will result in oxidization of copper. After plating, the fingerprint will appear obviously. The outline of the board will be seriously poor if the plating layer is not flat.
B. Toughing the printed circuit board with bare hands before solder mask, it will decrease the adhesion of the green oil and the green oil will peel off because there are bubbles during HAL (Hot Air Leveling).


C. Touching the PCB after solder mask until package with bare hands will cause unclean surface of boards and poor soldering.
D. There is fingerprint with grease when print wet film or silk screen, it is easy to cause the adhesion of the dry or wet film to decrease, causing the separation of cementation and plating layer during plating.
Solutions
A.It is required to develop a good habit about fetching and putting the PCB.
B.It must wear gloves when touch the printed circuit board.
C.Setting an example and keeping the rule of in mind–do not touch the board with bare hands.
Best Technology is the premier expert in PCB manufacture of electronics, brings a unique combination of technology and quality that offers a competitive supply of printed circuit board and PCBA. With high qualified engineers, we are able to help you find a PCB with high quality. To find out more, contact Best Technology at 0755-29091601 or check the website: https://www.bestpcbs.com/

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5 Views on Explaining Why the PCB Is Green

Wednesday, January 2nd, 2019

At the first sight, you will see that there is a layer of green oil on the PCB. It is called solder mask which is comprised of resin, talc and pigment. Of course, solder mask also has other colors, including red, yellow, black and so on, but green is the one that used the most widely.

When it comes to the question like that “Why are the most of printed circuit boards are green?”, the engineers from Best Technology with rich experience gave 5 points to explain it:

1. There PCB is required to go through the exposure room with yellow light in some processes of fabrication and the visual effective in exposure room is better than the solder mask with other colors.

What’s more, the PCB needs to coat tin, SMT and AOI testing during SMT soldering. All of these processes require optical position alignment and the green solder mask is better for the recognition of instruments.

PCB with green solder mask

PCB with green solder mask

2. Before the flying probe testing is applied widely, most of the wires on the PCB are relied on the naked eyes to inspect.It is very tired to detect the boards in strong light. If the rigid board is green, it will not do a lot harms to eyes.

3. There are cobalt and carbon in  blue and black solder mask,which have a certain conductivity, so there is a risk of short circuit. However, the PCB with green oil will be more friendly to the environment. Because it will not release poisonous gases when use the printed circuit board in a high temperature environment.

printed circuit board with green solder mask

printed circuit board with green solder mask

4. Since some famous brands began to use black solder mask in 2007, such as ASUS and Micro-Star and then people kept an eye on the colors of PCB.In this way, people gradually believe that PCBs with black solder mask means that the boards have high quality.After that, more and more PCB manufacturers started to apply black solder mask. NO one said that printed circuit boards with black solder mask are better than those with green solder mask.It is entirely due to the misleading caused by the famous brands using black solder mask to identify product positioning.

5. There is no reason, just because of habit, so it has been used all the time.

Best Technology is the premier expert in PCB manufacture of electronics, brings a unique combination of technology and quality that offers a competitive supply of printed circuit board and PCBA. With high qualified engineers, we are able to help you find a PCB with high quality. To find out more, contact Best Technology at 0755-29091601 or check the website: https://www.bestpcbs.com/

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Superfast Internet 5G Brings Endless Possibilities for PCB

Wednesday, December 26th, 2018

Every day you can read about 5G in the news and it brings superfast Internet for daily life. Recently, China Mobile took the lead in opening a 4.9GHz 5G base station in Beijing. It is reported that the base station is located in the CBD (Central Business District) of Beijing, and the single-user download rate can be as high as 2.8 Gbps. The base station adopts Huawei’s 64T64R AAU5913, and the frequency bandwidth is up to 100MHZ, which can maximize the use of the current website to cover both 4G and 5G sites.

China Mobile opening the 4.9GHz 5G base station in Beijing will accelerate the development of 4.9GHz 5G in industrial chain. Meanwhile, it also brings endless possibilities for fields, including smart traffic, smart city, UHD (Ultra High Definition Video) etc..

 

8L HDI PCB

8L HDI PCB

Accelerating the application of 5G not only facilitates the development of above fields, but also opens up a lot of possibilities for printed circuit board. The building of base stations will need many PCBs with high frequency and high speed.

Best Technology is the premier expert in manufacture of PCB and PCBA. Our PCB designers are highly qualified and experienced and can give you a competitive supply of printed circuit board. To learn more, contact us at 0755-29091601 or check our website: https://www.bestpcbs.com/

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Outlook of Headphone, Outlook of Wearable Devices

Wednesday, December 19th, 2018

People always find ways to decorate the electronic products those have been accompanied with them for a long time. Change a phone cover according to the dressing style or change a watch strap with different colors for Apple Watch. It seems that the technology devices have already become our accessories.

It has been a long time that technology combined with fashion. After all, a word “techno-fashion” became prevailing at the very beginning of 20th century. Therefore, we are able to see that Nike & Adidas do the same thing as a technology company — developing their new shoes. Meanwhile, Apple and Hermes launched Apple Watch to enter the luxury market.

It might be not very significant to say using technology to set off fashion or using fashion to set off technology, especially the wearable devices have begun to blend with daily dressing. And we have to admit that the headphone is the darling in the fashion crowds.

A number of NBA starts wore Beats to enter the field at the opening ceremony of 2008 Olympic Games. Since then, Beats headphone has become a fashion item favored by many stars and it can be seem in the street shoots or portraits of stars such as Lady Gaga, Justin Bieber, GD etc..

NBA's star wear Beats headphone in training

NBA’s star wear Beats headphone in training

Super model Cara wear Beast in street shoot

Super model Cara wear Beast in street shoot

Driven by Beast, headphone has become a fashion trend for many luxury brands. For example, the controversial fashion brand D&G launched their luxury headphone on the fashion show some time ago.

luxury headphone from D&G

luxury headphone from D&G

A lot of KOLs on Instagram are also fond of to show their own photos wearing AirPods. It seems like that AirPods has been their new earrings.

Some people hold that AirPods will be more easier to match their suits. A young man wore AirPods for his interview and he said that it was more fashionable. After all, advance technology is always more fashionable.

A young man and AirPods

A young man and AirPods

It is well known that headphone is a little gadget with small volume. Therefore, one of  the biggest challenges to make headphone integrates with wearable devices is that whether the components are small enough. For example, whether the printed circuit board are small enough to fit into the headphones.

Best Technology, a professional PCB solution provider, is always dedicated to catch up with times. Our unique technology and high quality products will give you a competitive supply of printed circuit board and rigid-flex circuit board and make your wearable devices more excellent. To learn more, contact us at 0755-29091601 or check our website: https://www.bestpcbs.com

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