日志

OSP PCB surface processing process and advantages

01/11/2024 在： /通过：

OSP (Organic solderable preservatives) is a lead -free surface treatment process, which is mainly used for SMT surface -packed circuit boards. Compared to the traditional HASL (HOT Air Solder Leveling) process, the OSP process does not require high -temperature melting treatment, which can reduce the risk of metal corrosion, environmental pollution and electronic component damage, so it is widely used in the electronic manufacturing industry.

OSP principle

The basic principle of the OSP process is to coat a layer of organic substances on the PCB surface to form a protective layer to prevent copper surface oxidation and corrosion. This protective layer is generally mixed with chemicals such as organic acids and nitrogen. The main chemicals include:

1. Organic acid: such as acetic acid, propionic acid, etc., mainly used to regulate pH values and enhance chemical reactions.

2. Nitride compounds: such as nitric acid, nitrite, etc., which are mainly used to increase the adhesion and durability of the protective layer.

3. Other additives: such as surfactants, anti -oxidants, etc., to increase the stability and durability of the coating agent.

Step of OSP process

1. Pre -processing: Chemical treatment on the PCB surface, remove oxides and pollutants, so that the surface is clean and smooth, which is convenient for subsequent coating and response.

2. Coating: Apply a layer of OSP coating agent on the surface of the PCB, and form a protective layer through drying and other processes.

3. CIT of: Put PCB in a cured furnace, heated it to a certain temperature, so that the OSP coating agent is solidified to form a protective film.

4. Detection: The solidified PCB is detected, including testing of indicators such as adhesion, thickness, and flatness.

5. SMT Paste: Put the electronic component on the surface of the PCB processing after OSP processing.

 

The OSP process has the advantages of environmental protection, lead -free, and suitable for microelectronics manufacturing. However, its processing process is more complicated and requires strict control of the composition and quality of coating agents to ensure the quality and stability of PCB. When using the OSP process, you need to pay attention to the following issues:

1. The composition and quality of theOSP coating agent have an important impact on the quality and stability of PCB. It should be selected for the appropriate chemicals and suppliers to avoid using inferior coating agents.

2. The coating thickness of theOSP coating agent also has an important impact on the quality and stability of PCB. It should be selected different thickness according to different PCB requirements. Generally speaking, the thickness of OSP coating agent should be controlled at 0.2-0.5um. between.

3. The curing time and temperature of theOSP coating agent are also very important for the quality and stability of the PCB. You should choose the appropriate curing conditions according to different coating agents and PCB requirements.

4. The adhesion and durability of theOSP coating agent are also the key indicators of the quality of PCB. It should be ensured by strict quality testing and testing to ensure its quality and stability.

5.OSP process is a green and environmentally friendly lead -free surface treatment process. It uses organic polymers as coating agents to form a protective film on the PCB surface to protect the PCB surface without oxidation or corrosion. Compared with the traditional Hasl process, the advantage of the OSP process is that the coating agent is environmentally friendly, uniform coating, non -welded ball, and easy to weld. Therefore, in modern electronics manufacturing, the OSP process is widely used.

OSP advantage

The advantages of OSP can be summarized as:

• Simple process and reusable use: The circuit board with OSP can easily be re -made by PCB manufacturers. In this way, once the PCB preparation personnel find that the coating is damaged, the new coating can be used.

• Good wettability: When the welds encounter holes and pads, OSP coated circuit boards perform better in welded wetting.

• Environmental friendly: Because water -based compounds are applied in the generation of OSP, it will not cause harm to the environment, and it will only fall into people’s expectations for the green world. Therefore, OSP is the best choice for electronic products that meet green regulations such as ROHS Essence

• PCB cost benefits: As simple compounds and simple manufacturing processes are applied during the OSP manufacturing process, the cost of OSP in all types of surface processing is very prominent. Its cost is lower, resulting in the lower cost of the final circuit board.

• Return welding suitable for double -sided SMT assembly: With the continuous development and progress of OSP, it has been accepted by single -sided SMT assembly and double -sided SMT assembly, which greatly expanded its application field.

• Low welding ink requirements: The storage requirements of OSP PCB for long storage time requirements Due to the very thin preservatives produced by OSP technology, it is easy to cut, so it must be very careful during transportation and transportation. OSP is exposed to high temperature and high humidity for a long time as a surface -processed PCB, which may occur on the surface of the PCB, which often causes low -weldability.

How OSP Manufactured

1.The first step is cleaning, which removes organic contaminants such as oil and oxidation films from the copper foil, the main component of the OSP. Insufficient cleaning can result in an uneven thickness of the created preservative. To achieve high-quality OSP films, the concentration of the cleaning liquid must be within a certain range according to laboratory standards. The cleaning process must be regularly monitored to ensure the required standard is met. If the desired results are not achieved, the cleaning liquid should be changed.

2.The second block is Topography Enhancement, where micro-etching is used to remove the oxidation produced on the copper foil that causes strong bonding between the copper foil and organic solderability preservative solution. The film build rate depends on the micro-etching speed. To achieve a smooth film thickness, the speed of micro-etching must be stable. The range for micro-etching speed is about 1.0 to 1.5 micrometers per minute.

3.The best option is to use a rinse before creating the preservative, as OSP solution can get polluted by ions, which can cause tarnishing after the completion of the reflow soldering process. In addition to that, DI rinse must be used after the creation of the preservative with a pH value of 4 to 7. If these parameters are not followed, the preservative can be destroyed due to pollution.

4.The OSP PCB coating is then applied to the cleaned copper surface through an adsorption process. The OSP solution contains organic compounds such as benzimidazoles, imidazoles, and benzotriazoles that form a thin layer on the copper surface. The thickness of the coating can be controlled by adjusting the concentration and immersion time of the solution.

5.After the coating is applied, the PCB is dried and cured in a controlled environment to remove any remaining moisture and to ensure proper adhesion of the OSP layer.

6.Once the coating is applied, the PCB is inspected for any defects or irregularities. The OSP-coated circuit boards are then subjected to various PCB tests to ensure their quality, reliability, and performance.

Application of Multi-layer PCB in electronic manufacturing

01/05/2024 在： /通过：

Electronic equipment can be seen everywhere in our lives, and some electronic products have become our indispensable supplies. We depend on them, while electronic equipment depends on the printing circuit board. PCB is the core component of most products now, and the basic functions are determined through the combination of components and wiring mechanisms.

PCB is divided according to the level, which can be divided into: single -layer circuit board, double -layer circuit board, and multi -layer circuit board. What we want to discuss today is the multi -layer circuit board. The simple -functional circuit board mainly uses a single-layer PCB, but more complicated electronic products, such as the computer motherboard, consist of multi-layer. With the increasingly complex of modern electronic products, these multi -layer PCB are more popular than ever, and manufacturing technology has greatly reduced their size.

What is multi-layer PCB

Multi-layer PCB is a printing circuit board composed of a multi-layer conductive layer and insulating layer. This circuit board is mainly used in high-end electronic products, such as wireless communication, computer, industrial automation, medical equipment and other fields.

Multi -layer PCB is composed of multiple conductive layers, which are separated from each other through the insulation layer. On each conductive layer, there is a layer of thin copper foil, which forms circuit graphics by chemical etching or mechanical drilling. The adjacent conductive layers are connected through the hole.

Compared with single -panels or double panels, multi-layer PCB has higher circuit density, better electromagnetic compatibility, lower circuit noise and better heat dissipation performance. Its production process is relatively complicated, and multiple steps such as copper foil coverage, chemical etching, drilling, printing, copper plating and other steps are required. These steps require high technical level and strict process control to ensure the quality and stability of the final product.

The design and manufacturing of multi-layer PCB requires many factors, such as appearance, size, number of layers, how to place components, how to arrange wires, drilling, pads, etc. The key is to optimize the internal wiring to improve the performance and reliability of the circuit.

Multilayer PCB Benefits

From a technical point of view, multilayer PCBs present several advantages in design. These benefits multilayer PCBs present include:

• Small Size: One of the most prominent and lauded benefits of using multilayer PCBs lies in their size. Because of their layered design, multilayer PCBs are inherently smaller than other PCBs with similar functionality. This presents a major benefit to modern electronics, as the current trend is working toward smaller, more compact yet more powerful gadgets like smartphones, laptops, tablets and wearables.

• Lightweight Construction: With smaller PCBs comes less weight, especially as the multiple connectors required to interlink separate single and double-layered PCBs are eliminated in favor of a multilayered design. This, again, is beneficial for modern electronics, which are geared more toward mobility.

• High-Quality: Due to the amount of work and planning that must go into the creation of multilayer PCBs, these types of PCBs tend to be better in quality than single and double-layer PCBs. They also tend to be more reliable as a result.

• Increased Durability: Multilayer PCBs tend to be durable by their nature. Not only do these multilayer PCBs have to withstand their own weight, but they must also be able to handle the heat and pressure used to bind them together. On top of these factors, multilayer PCBs use multiple layers of insulation between circuit layers, binding it all together with prepreg bonding agent and protective materials.

• Enhanced Flexibility: Though this does not apply to all multilayer PCB assemblies, some do use flexible construction techniques, resulting in a flexible multilayer PCB. This can be a highly desirable trait for applications where mild bending and flexing may occur on a semi-regular basis. Again, this does not apply to all multilayer PCBs, and the more layers incorporated into a flexible PCB, the less flexible the PCB becomes.

• More Powerful: Multilayer PCBs are extremely high-density assemblies, incorporating multiple layers into a single PCB. These close-quarters enable boards to be more connective, and their innate electrical properties allow them to achieve greater capacity and speed despite their smaller size.

• Single Connection Point: Multilayer PCBs are designed to work as a singular unit, rather than in tandem with other PCB components. As a result, they have a single connection point, rather than the multiple connection points required to use multiple single layer PCBs. This proves to be a benefit in electronic product design as well since they only need to include a single connection point in the final product. This is particularly beneficial for small electronics and gadgets designed to minimize size and weight.

These benefits make multilayer PCBs highly useful in a variety of applications, particularly mobile devices and high-functioning electronics. In turn, with so many industries turning to mobile solutions, multilayer PCBs are finding a place in an increasing number of industry-specific applications.

Advantages of Multilayer PCBs over Single Layer Alternatives

When compared to single layer alternatives, the advantages of multilayer PCBs become even more pronounced. Some of the key improvements multilayer PCBs offer include the following:

• Higher Assembly Density: While single layer PCBs’ density is limited by their surface area, multilayer PCBs multiply their density through layering. This increased density allows greater functionality, improving capacity and speed despite the smaller PCB size.

• Smaller Size: Overall, multilayer PCBs are smaller in size than single layer PCBs. While single layer PCBs must increase the surface area of the circuit by increasing size, multilayer PCBs increase surface area through the addition of layers, decreasing overall size. This allows for higher-capacity multilayer PCBs to be used in smaller devices, while high-capacity single layer PCBs must be installed into larger products.

• Lighter Weight: The integration of components in a multilayer PCB means less of a need for connectors and other components, resulting in a lightweight solution for complex electrical applications. Multilayer PCBs can accomplish the same amount of work as multiple single-layer PCBs, but does so at a smaller size and with fewer connecting components, reducing weight. This is an essential consideration for smaller electronics where weight is a concern.

• Enhanced Design Functionality: Overall, multilayer PCBs are capable of being more than the average single layer PCB. With more incorporation of controlled impedance features, greater EMI shielding and overall improved design quality, multilayer PCBs can accomplish more despite their smaller size and lesser weight.

Application of Multilayer PCB

Multi-layer PCB is widely used in various high-end electronic products, including but not limited to the following fields:

1. Communication equipment: Multi-layer PCB plays a key role in communication devices such as mobile phones, routers, satellite communication, etc., and realizes high-speed data transmission, signal processing and power management functions.

2. Computer hardware: Multi-layer PCB is widely used in hardware such as computer motherboards, graphics cards, and memory strips. It provides high -density and high reliability circuit wiring to ensure the stable operation of the computer system.

3. Industrial automation: Multi-layer PCB is widely used in industrial automation equipment, such as programmable controllers, sensors, motors controllers, etc. Its high reliability and durability meet the needs of industrial automation equipment.

4. Medical equipment: Multi-layer PCB is also widely used in medical equipment, such as monitor, ECG, ultrasound equipment, etc., its miniaturization, high density and reliability provide strong support for the performance of medical equipment.

5. Aerospace: The application of multi-layer PCB in the field of aerospace is very important because this field requires high reliability and durability electronic equipment. The characteristics of high-density wiring, electromagnetic compatibility and heat dissipation performance of multi -layer PCB meet the needs of the aerospace field.

6. Car Electronics: Multi-layer PCB is also widely used in automotive electronics, such as engine control modules, airbag control modules, etc. Its high reliability and durability can ensure stable operation in the harsh working environment of the car.

Get a Manufacturer For Your Multilayer PCB

Lst is a Custom PCB SORUTIONS Provider, Serving Companies the World in PCB ManuFacturing and Assembly Services. We Help Companies Sourcing To Testing, ALL The Who Remaining Compliant with IPC Class 3, Rohs and ISO9001: 2008 Standards.

We can design a variety of complex multi -layer circuit boards for you. We have an experienced production technology team to track the processing of multi -layer circuit boards throughout the process. Any of your needs, LST can be met.

15 common PCB faults and solutions

01/03/2024 在： /通过：

Regardless of whether it is an engineer or a PCB manufacturer, it is impossible to avoid PCB failures. The emergence of these faults may lead to delayed product intersection and affected the reputation of the manufacturer, increasing time and money costs.
Today is mainly about the PCB fault mode and the PCB failure solution. Here we mainly list the following 15 PCB fault modes, let’s analyze this.

1. PCB crack or bend

Reason: Due to high mechanical or physical stress, printing circuit board components (PCBA) may be ruptured or bent. For example, if the rigid PCBA is placed under repeated vibration or thermal shock, it may fail. In addition, if your curved strength exceeds its ability, even flexible PCBA will break.

PCB crack

Prevention method: Before using PCB during the assembly process, bake PCB and store it in a cabinet with humidity control to remove any water in the naked PCB to avoid impact caused by the later stages of assembly.

2. The assembled PCB components have obvious polarity

Reason: When designing the PCB layout, if the component on the printed circuit board component is not obvious, it may lead to the problem of polar counter -connection. For example, if the battery pole is reversed, the battery and electrical components may be damaged. Printing circuit board components may also fail, and electric shocks may occur.

PCB components have obvious polarity

Prevention method: You can use diode or Schottky diode to reduce the effects of reverse polarity. If you connect the diode with the battery, the circuit will be turned off in the opposite situation, it will prevent any major damage to the printed circuit board component.

3. PCB solder joint break

Reason: The difference between the thermal coefficient and electronic component of the PCB may cause the solder joints to break. If the printed circuit board components are placed in a repeated high or low temperature environment, a failure may occur. Another reason may be manual welding, which makes welded more vulnerable to thermal stress.

PCB solder joint break

Prevention method: It would be much better if you use a special automatic machine to welded electronic components. Before sending the PCB to the assembly process, make sure you have visited inspection.

4. PCB corrosion

Reason: Since there may be some residues during the PCB assembly, there may be some residues, so the printed circuit board component may be corroded. The welding agent is essential to ensure the safe connection of electrical components. However, once contact, it will also cause their corrosion.

Prevention method: Welds are composed of organic acids, such as citric acid or adenic acid. PCB assemblers should ensure that any extra welded agents are eliminated from the PCB surface. This will not help the solder to destroy the metal contact. If the PCB assembler uses a refund welding machine, you should remember to rinse any excess welding agent.

5. Burning or burning electronic components (short circuit)

Reason: During the PCB assembly, short circuit may damage PCB and electronic components. This may be short circuit due to the unexplained welding bridge, humid or accidental events (such as high -current peaks). Short -circuit will cause sudden and sudden damage to components, and may also cause damage to fire and electrical equipment.

Prevention method: Check the short -circuit situation of the PCB surface. For the inner layer, electrical testing is most suitable for the assembly of printing circuit boards. The test mainly checks whether there is short -circuit or opening. In addition, you can compare the obtained readings with the readings obtained from the probe test.
In addition, when designing the PCB layout, PCB assembly personnel must accurately align each layer. In this way, they will be able to work together and avoid any short circuits. You can also reduce the thickness of the PCB template to reduce the deposits of welded paste.

6. Copper weight is not suitable

Reason: For the good current in the printing circuit board component, the weight of the correct copper foil is necessary. If the copper weight is too thin or too thick, it will cause your print circuit board component to fail, which is mainly because the size determination and the width selection of the wiring width when designing the PCB layout.

 

Prevention method: PCB assemblers must follow the copper weight specifications required by PCB engineers. Copper cannot be too thick because it increases costs and cannot be too thin, because they may cause PCB to heat up.

7, component position movement

Reason: In PCB assembly, pick up and place or place components of the circuit board in other automatic machines. If the component is shifted or moved due to the welded weld during welding, the PCB may be faulty. It is mainly because reliable solder joints will not be formed and may cause the road.

Prevention method: PCB assemblers should follow the standard humidity and temperature requirements. They may use more accurate pickup and placing machines to accurately place components. In addition, if you still use more corrosive welding agents, it will improve the weldability of parts, which can keep the electronic components in the original position.

8. The warranty period of electronic components expires

Reason: If any single component in the printed circuit board component fails, it may cause the entire PCB component to collapse, and parts may fail due to reverse selection. If these components are not limited, they will be helpful. In addition, if you choose a low -quality component, it will reduce the service life of the parts, and it may not even be before the warranty period expires.

Prevention method: You should carefully select the component or ask your PCB factory to do so. The parts should not be damaged or the quality should be low (electronic component preparation). In addition, you can directly add components to prepare damage.

9. PCB hot pressure or wet pressure

Reason: Different materials have different expansion rates. Therefore, when a constant a thermal stress is applied, it will damage the solder joint and damage the component. If the wrong copper weight or electroplating problem is used, the stress of thermal factors will increase. Even in the process of manufacturing, the temperature of the assembly PCB room will affect its performance.

Prevention method: PCB assembly personnel must conduct a careful circuit board inspection, prepare, and then clean the necessary cleaning. Pencil rubber rubbing can eliminate any slight corrosion or rust. You can identify the sub -light copper pad through their dark brown. Welds are not sticky to the surface of rust, and must be applied after cleaning, and excess is removed with the welding core.

10. Problems of PCB welding process

Welded welds are very important for the work of electronic circuits, so pay more attention. The most common problems related to soldering are the conditioning conditions for welded pollution and bad processing. The welding agent is a chemical cleaner used before and during the circuit board. Some welded residues will absorb the possible conductive moisture, which will cause short circuit. If the welding process is not set and controlled correctly, the connector can be opened and pollution.

11. PCB uses physical problems of materials

The materials used in PCB often encounters problems that cause the circuit board to fail. In the manufacturing stage, if a layer of PCB is not aligned, it will cause short -circuit, opening and cross -signal lines. If the material has a psychological defect such as breaks, empty holes, and layered, the performance of PCB will be seriously affected. If the material used is not pure, it will also fail.

12. Chemical fluid leaks in electronic components in PCB

The existence of any chemical liquid leaked in the component will severely damage the PCB and cause failure. Most chemicals are removed during the manufacturing process. However, trace elements may be left. Inside the packaging of the component, leaks may occur, which will cause semiconductors or packaging rapidly. This chemical leak will eventually lead to short -circuit or corrosion.

13. PCB component design failed

One of the most common reasons for PCB failures is incorrect components due to insufficient PCB space, power failure or overheating. Space is crucial, especially when the circuit board becomes more complicated and needs to meet harsh requirements. Here are only some examples of errors in the design and manufacturing stage. Don’t forget, you can avoid many such problems by following the correct PCB design rules.
Welding problem
Chemical (fluid) leakage
Component barrier damage
Wrong component placement
Burning component

14, inferior electronic components

It is not so easy to find an electronic component that conforms to the circuit design. Whether it is to ensure packaging or management components, it is very important to find high -quality electronic components when considering PCB assembly and manufacturing.
The tightly placed wiring and channels, poor welding of cold welds, poor connection between circuit boards, insufficient circuit board thickness, and use of counterfeit elements are just some problems that may face.

15. PCB placement environment

PCB is exposed to heat, dust and humidity, accidental impact (falling and falling), and power supply/waves, which may be the cause of circuit board failure. However, the most destructive reason for the premature failure of the circuit board is the electrostatic discharge (ESD) in the assembly stage. Electricity discharge (ESD) is a sudden current flow caused by short circuit or dielectric breakdown between the two electric objects. Static accumulation may be caused by friction charging or electrostatic sensing.

The specifications and requirements of PCB Silkscreen designed.

12/28/2023 在： /通过：

PCB Silkscreen design mainly refers to the design of the silk layer printing on the printing circuit board (PCB). The silk layer is a special layer on the PCB, which is used to print various texts, symbols and graphics, such as circuit points, components, circuit symbols, etc. This information is mainly used for various components and functional areas on the identification, identification and management of PCB.

In the PCB Silkscreen design, many factors need to be considered, such as space restrictions, information importance and readability. Due to the limited PCB surface space, designers need to decide which information is the most critical and prefer to display this information in the silk print layer. For example, component reference signs, polar marks, pins 1 labeling, component boundary, company logo, manufacturing trademark, warning symbols, component numbers, version numbers, and date code are all common silk print content.

Design PCB Silkscreen usually uses EDA (electronic design automation) software. Designers can identify and assemble all the necessary marks, symbols and texts required for components on PCB, and then export the format that can be used by manufacturers. Modern PCB Silkscreen design usually uses a digital inkjet printer to print the screen printing image to the surface of the PCB, while the initial screen printing technology uses the screen printing method.

Importance of PCB Silkscreen

In order to lay the right background on a silkscreen PCB role, it is important that we recall the uses of a printed circuit board (PCB). PCB offers mechanical support and helps in connecting electronic components. PCBs have signal traces, conductive pathways, or copper sheet-etched traces that are laminated to a substrate (non-conductive).

The conductive tracks and components of the PCB are seen throughout the board without the right identification. This is why it is necessary for end-users and manufacturers to exist. This helps them to identify components such as:

▶Manufacturer identifiers
▶Testing points
▶Warning signs like high voltage
▶Processing types
▶Version numbers like V2, V3, etc.
▶Component orientation and numbers
▶Company logos i.e. manufacturer name

The importance and roles of silkscreen PCB include:

▶Identifying circuit points such as part interconnect, testing points, etc. quickly
▶Useful in troubleshooting circuits in case you get a defective component or a contrasting outcome
▶It helps you quickly identify components whenever you are designing or replacing evaluation requirements.
▶It serves as a form of safety by showing some warning signs, such as grounding, high voltage, etc.
▶Silkscreen PCB also helps manufacturers dung marketing and branding purposes. However, it prevents illegal duplication or forgery of circuit designs.

Silkscreen PCB is also great for evaluating products, such as rating verifications. Note that the information of your silkscreen depends on the size of your board. If your silkscreen board is a small one, make sure you take the important information seriously.

Silk print design requirements

The ratio of the word height to the word width of the silk print character is generally required ≥6: 1. There are three common font samples: where the board density is relatively large, the character of 4/25mil is commonly used (No. 1); when the conventional density is recommended, it is recommended to 5/recommended 5/ 30mil characters (No. 2); when the board is relatively loose, it is recommended to 6/45mil characters (No. 3); usually the thickness of the surface of the surface of the surface also has corresponding requirements for the width of the silk print: When the thickness of the base is 1oz, the 5/30mil character is preferred; when the base copies are 2oz, the 6/45mil character is preferred.

PCB Silkscreen requirements

1. Placement position: Generally speaking, the wire printing of resistors, capacitors, pipes and other devices should not be used in four directions when placing. This will cause debugging, maintenance, and welding.

2. Try not to hit the silk print as much as possible.

3. Do not press on the high -speed signal line (such as, clock line, etc.): For high -speed signal lines on the top or bottom layer, because this type of signal line can be regarded as a microstrip line.

4. The reading direction of the silk print should be consistent with the reading direction of the silk printing and the use direction of the chip. It is mainly because the probability of welding is reduced when welding.

5. The pins are clearly marked on the silk print.

6. Special packaging Silk Printing: For special packaging such as BGA and QFN, the size of the silk print must be exactly the same as the size of the chip.

7. Silk printing of the installation hole: The screws are added near the installation hole, and the total length and screws are marked for easy installation.

8. The two meaning of silk printing: the most commonly used RS232, many people will mark RX and TX, but there are RX and TX on the PC side. When do you use cross lines and when do you use it? Misty is unclear.

PCB Silkscreen design precautions

1. The width of the wire printing line on the board is ≥4mil, and the width of the component wire printing line is 0.

2. Silk printing and pad distance: Do not cover the welding point on the board, such as patch device pads, plug -in holes, silk printing as insulating material, once pads are put on , Mark point, etc.; usually require a 6mil spacing.  

3. Sitries between silk prints: It is acceptable to keep 6mil. There is a coincidence between the silk seal. Once the coincidence is overwhelmed, it needs to be adjusted.  

4. Silk printing direction: Silk print string arrangement should follow: the principles of string from left to right or from bottom to top when facing the right look.

5. The device bit number is placed: the device bit number should correspond to the device one by one, and cannot be reversed and transforms the order; when the density density is relatively high, you can use the method of drawing or symbolic labeling to place the bit number on the board other other boards. There is space.

6. The polar identity of the component and the “1” foot logo should be placed correctly and clearly.

7. When the labeling or symbol labeling, the added silk prints and characters added should be placed on the silk layer of Board Geometry.

The added board name number silk print is also placed on the silk seal layer of Board Geometry.  

8. The device bit number cannot be placed in the device or outside the board.  

9. When the density of the board is relatively high, when there is no space for placing the bit number, you can discuss with the customer not to sign, but you need to install pictures to facilitate the installation and inspection of the guidance device.

10. When the customer is required to write copper characters on the bottom layer, the line bronze line width: HOZ base bronze: character width above 8mil, height of 45mil or more; 1oz base bronze: more than 10mil in the character; above 50mil. At the same time, you need to do a good job of welding windows, so that the copper characters produced on the board are relatively bright.

Three Main Process Methods Of Silk Screen Printing.

The following are the most common PCB silk screen technology processes and processes on PCB:

▶Manual Silk Screen PCB: This process can be used when the line width is greater than 7mm and the registration tolerance is 5mm. For this method, you will need pcb silkscreen minimum text size and trace template made of nylon. The oil is printed onto the plate through the stencil. Next step,make the PCB board baked in a curing oven and let it to besolidification.

▶Liquid Photo Imaging (LPI): This procedure supplied greater correctness and legibility than manual screen printing. Using this method when the trace width is greater than 4 mil. Liquid photo imaging is very similar to the process of applying solder mask. In this case, a liquid photoimageable epoxy was applied to the laminate and then exposed to UV light. After that, the PCB board is developed and cured.

▶Direct Legend Printing (DLP): This is the most correct way to add PCB silk screen, but it is very high-priced. In such pcb silkscreen process, using an inkjet projector with acrylic pcb silkscreen ink, which have relevance to the original print circuit board from the CAD data. The pcb silkscreen acrylic inks is solid with UV light during printing. It should be noted that acrylic inks will not cure on boards with a silver finish.

Understand PCB Screen Printing Cost.

Due to the fixed cost characteristics, the cost of PCB screen printing is placed in the first place of non recurring tools in the PCB design process. PCB screen printing process accounts for about 15% of the total cost from PCB manufacturing cost.

1.The minimum text size design of PCB screen printing refers to the change of character width, height, PCB screen printing thickness, spacing and character position. Art fees are usually not charged separately.

2.The cost of PCB screen printing ink depends on the screen printing method used. Acrylic ink is used for the DLP method of legend printing, while other methods use epoxy ink.

3.The cost of PCB screen printing ink decided by specific features, such as curing procedure, adhesion,substrate compatibility, and immunity to acid / alkali treatment.

4.PCB screen printing color is also a decisive cost factor. The cost of white ink silkscreen is lower than that of other color inks. By optimizing the cost of PCB screen printing through the selection of PCB screen printing materials, the total cost of PCB can be reduced by about 5%.

5.The screen printing method that used also has an effect on the total cost. The cost of LPI for liquid photo imaging and DLP for direct legend printing is higher than that of manual screen printing because of the high capital cost of setup.

6.Another important factor to consider in the cost calculation of screen printing is whether you want to print legends on both sides or just on one side. In the case of both parties, the cost will rise.

Conclusion

The process of PCB silkscreen is delicate. This is because the quality of the printed circuit board can be affected. Another aspect you must consider closely is the cost aspect during the design. Furthermore, having a good understanding about the whole process of screen printing as well as the benefits and pitfalls of each of the printing methods ensures that it becomes easy to decide if you should do a DIY PCB silkscreen or consult the services of any professional manufacturer.

Quick Turn PCB Manufacturing Guide: How to choose manufacturer

12/26/2023 在： /通过：

Quick Turn PCB manufacturing means that PCB can complete mass production in a short time, so it is named “Quick Turn PCB”. Fast PCB can help customers realize the rapid entering the market, while ensuring sufficient capacity. High -quality, high efficiency, and relatively low cost make the Quick Turn PCB manufacturing very popular.

The advantage of fast PCB manufacturing

The advantages of fast PCB manufacturing mainly include the following points:

1. Quick delivery: The traditional PCB manufacturing process may take several days or weeks to complete, and the Quick Turn PCB manufacturing can be completed in just a few hours, which greatly shortens the product listing time.

2. High -precision: Quick TURN PCB manufacture uses high -precision laser or lithography technology, which can make PCB with high precision lines and details, which improves the reliability of the circuit.

3. Low cost: Although the initial investment manufactured by Quick Turn PCB may be high, due to its fast and high -precision characteristics, it can save a lot of time and cost in the long run.

4. Flexibility: Quick Turn PCB manufacturing allows designers and engineers to ite and modify during the manufacturing process to better meet product needs.

5. Customization: Quick Turn PCB manufacturing can customize the size, shape and materials of PCB according to the needs of the customer, thereby meeting various application needs.

Quick Turn PCB Prototypes

A PCB prototype is a fabricated PCB that is created to check and evaluate the functionality and capability of the final PCB assembly that is the objective of production, to make sure it meets the current required technical and electrical applications.

These prototype PCBs are created with all the functionalities and properties that are expected from the final finished PCBs. Prototypes help prove the PCB design, providing the avenue to thoroughly test it and resolve any performance or regulatory compliance issues before full manufacture commences.

The prototype stage is where the correction, addition, or omission of features are done to ensure that the final PCB assembly is without any technical errors. This is done before the quick turn automation begins in earnest. Therefore, valuable time is invested in prototype testing to support efficiency and performance.

Early prototypes can be drastically different from the finished product. Therefore, the first batch of prototypes is usually done in smaller quantities. Prototypes are crucial because it is difficult to make changes to a finished PCB.

Quick turn PCB prototypes are therefore beneficial for the following reasons:

●Save significant manufacturing costs.

●Avoid manufacturing defects or spotting them at an early stage for correction.

●Save valuable delivery time by meticulously checking the design for manufacturability.

●Avoid manufacturing delays by reducing changes during production.

●Provide chances for manufacturers to make adjustments before full production, based on client and user feedback.

How to ensure the quality of Quick Turn PCB manufacturing

To ensure the quality of the Quick Turn PCB manufacturing, the following measures can be taken:

1. Choose high -quality manufacturers: Choose a fast PCB manufacturer with good reputation and rich experience to ensure that its production technology and equipment meet industry standards.

2. Provide clear design files: ensure clear and accurate design files provided to the manufacturer, including the correct component layout, size, spacing and other details to avoid errors in the manufacturing process.

3. Make quality inspection: In the process of PCB manufacturing, quality inspection is very important. This includes random inspections of various stages of the manufacturing process to ensure that the PCB produced meets design requirements and quality control standards.

4. Perform factory testing: After the PCB manufacturing is completed, it is necessary to conduct a comprehensive factory test. This includes electrical performance testing, appearance inspection and dimensional measurement to ensure the quality and reliability of PCB.

5. Use automation equipment: The use of automated equipment for PCB manufacturing and testing can reduce human errors and improve production efficiency, thereby ensuring product quality.

6. Strengthen communication and collaboration: Maintain close communication and collaboration with the manufacturer, timely solve the problems in the manufacturing process, and ensure that the quality of the product has been improved and improved in a timely manner.

7. Standards and specifications: Follow the relevant PCB manufacturing standards and specifications, such as IPC standards to ensure that the PCB created has good reliability and consistency.

What Are The Factors That Affect The Delivery Time Of Quick Turn PCB?

1. The complexity of PCB design. Many PCB manufacturers claim to provide the same day PCB, next day PCB, or 24 hours PCB manufacturing services. But please don’t be deceived by the simple statements. The simple design of single-sided PCB or double-sided PCB can be delivered within 24 hours, while the turnaround time for more complex designs of flexible PCB and rigid-flex PCB takes 7-10 days.

2. PCB materials. Different PCB types require different production materials, and not all PCB manufacturers have stocks of unique material. When ordering PCBs, it is necessary to consider the purchase time of PCB raw materials.

3. Difficulty factor of PCB process. We know that there are various holes on the PCB, such as plated through holes, blind holes, buried holes, etc. Each blind hole and buried hole needs to use a drill or laser drilling, and drilling, lamination, electroplating, etc. require additional time. HDI PCB takes more time.

4. The manufacturing capabilities of PCB manufacturers. You need to check your PCB manufacturers’ infrastructure to determine if they meet your fast turnaround time needs.

Some factors you need to consider are:

♦The size of the PCB manufacturing company;
♦Whether they have invested in advanced production equipment;
♦Whether they can control and influence material suppliers;
♦Whether they can purchase high-quality PCB raw materials;
♦Whether the PCB manufacturing company manufactures in-house or partially outsources;
♦Do they have professional PCB engineers;
♦Their logistics capabilities: logistics methods, relationships with logistics partners, etc.;

5. Pricing

Please believe in the eternal truth: the cheapest is not necessarily the best. All PCB manufacturers have their characteristics and strengths in terms of quality, turnaround time, and price. We need to evaluate based on the comprehensive capabilities of the PCB manufacturer and the complexity of the PCB itself.

How to choose a Quick Turn PCB manufacturer?

When choosing a Quick Turn PCB manufacturer, you need to consider the following aspects:

➤Quality assurance: First of all, the quality assurance system of the manufacturer needs to be examined, whether it has passed the quality certification such as ISO 9001, and whether there is a strict quality control process.

➤Experience and professionalism: Choose manufacturers with rich experience and professional knowledge to better understand your needs and provide high -quality services.

➤Equipment and technology: Examine the equipment and technical level of manufacturers, including manufacturing equipment, technical technology, testing equipment, etc. to ensure its ability to make fast and high -precision manufacturing.

➤Delivery time: Understanding the delivery time of the manufacturer can meet your emergency needs.

➤Price: Compared the price of different manufacturers, and at the same time, considering factors such as quality, delivery time, and the highest price -effective supplier.

➤Services and after -sales: Choose a manufacturer with good pre -sales and after -sales service, which can solve the problems of manufacturing and after -sales problems in a timely manner.

➤Cases and reference: View the cases and customer feedback of the manufacturer to understand their actual performance and reputation.

When choosing a fast PCB manufacturer, it is recommended to conduct field inspections to understand its actual production situation in order to make more accurate judgments. At the same time, you can refer to the recommendations and evaluations of the same industry in order to better choose a reliable manufacturer.

Choose LST technology as your PCB manufacturer

We are Chinese professional fast PCB manufacturers. We have the industry’s leading on time and effectively solve many urgent problems for customers.
With our manufacturing facilities, we can provide all types of industries with fast circuit board manufacturing services and fast PCB prototype solutions, including medical, transportation, industrial applications, consumer goods, aerospace and military.
Each online PCB order includes a comprehensive engineering review before the start of circuit board manufacturing, eliminating delay and quality problems.

How to choose the correct PCB manufacturer in China?

12/21/2023 在： /通过：

If you are looking for a PCB manufacturer, China is undoubtedly a very good choice. China is currently the world’s largest PCB production base. It has advanced production technology and low production costs, so many companies choose to assemble PCB in China. Of course, China also has some small processing plants. Their strength is not so strong, and lacks certain competitiveness in high -end fields. Enterprises must also take comprehensive considerations when selecting PCB suppliers to ensure the smooth production plan.

We will focus on this article: how to choose the correct PCB manufacturer in China, we will discuss quality control measures, industry experience and customer support, and provide research and potentially communicating with potential manufacturers. At the end of this article, you will better understand what you should find among reliable PCB manufacturing partners, and how to find partners who meet your specific requirements.

Why choose China for your next PCB manufacturing project?

1.The country is emerging as a leading PCB manufacturing hub with an increasing global share of PCB output.

2.Almost all kinds of PCBs and various scales of manufacturing projects are efficiently dealt with in the country. Therefore, no matter what type of PCB manufacturing requirement you have, China has a company that offers you exactly the same.

3.Chinese manufacturers possess unmatched technical expertise, advanced technology and precise equipment to eliminate chances of errors and defects in the final product.

4.Like most electric and electronic components, custom-designed PCBs are also available at affordable prices in China.

5.In China, PCB manufacturers usually depict a top-notch level of professionalism. They offer exceptional client handling and service support. This helps customers stay updated throughout the manufacturing process. Chinese manufacturers prioritise communication which further helps build trust and a strong partnership between the customer and the manufacturing company.

What should you do before looking for PCB manufacturers?

Before looking for PCB manufacturers, you should be clear about your needs, including the specifications, types and functions of the PCB board, while understanding the product’s budget, mass production requirements, and the required delivery time. In this way, you can choose the right manufacturer to cooperate.

Specifically, you need to examine the professional level of the manufacturer, including the level of process, the degree of advancement of equipment and technology, and the operating efficiency of the production line. At the same time, paying attention to product quality, good manufacturers can not only meet the quality requirements, but also provide a longer warranty period. Considering the production capacity of the manufacturer, whether it can meet your production needs and ensure the timely delivery of orders. In addition, the price is also an important factor in choosing a manufacturer. It needs to evaluate whether the cost it costs costs cost -effective and whether it is in line with market price.

The factors that you need to consider when choosing a PCB manufacturing company

When choosing a PCB manufacturing company, you need to consider the following factors:

1. Production capacity: Ensure that the manufacturer has sufficient production capacity, can deliver orders on time and meet production needs.

2. Technical strength: Examine the technical strength of the manufacturer, including the technology, experience and equipment it own to ensure that it can provide high -quality products and solutions.

3. Quality control: Understand the manufacturer’s quality management system and quality control process to ensure that it can provide stable and reliable product quality.

4. Dating period: Dating is an important factor in measurement of the production capacity and efficiency of PCB manufacturing companies. It is necessary to ensure that the manufacturer can deliver orders on time and meet production needs.

5. Service level: Examine the level of pre -sales, mid -sales, and after -sales service levels, including technical support, maintenance, repairs, etc. to ensure that it can solve customer problems in time and provide technical support.

6. Cost benefits: Evaluate the price and delivery cycle of the manufacturer, whether it meets the budget and mass production requirements, and whether it can reduce the cost on the premise of ensuring the quality of the product.

7. Reputation: Understand the reputation and reputation of the manufacturer, including the rate of return of history and business, customer feedback information and evaluation rankings, etc., to ensure that it can ensure product quality and service level.

The way to find Chinese PCB manufacturers

Now you may want to know where and how to find the best company. To this end, you need to conduct thorough research and list the finalists according to the above list. To find your option:

1. Take a look at the Internet

2. Browse list platform/directory

3. Visit exhibitions, conferences and trade exhibitions

4. Recommended and recommended by colleagues or contacts in the industry

Communication with PCB Manufacturing Companies

Effective communication is key to establishing a successful partnership with a PCB manufacturing company in China. Here are two key aspects to consider when communicating with potential manufacturers:

▶Initial Contact
When reaching out to potential manufacturers, it’s important to prepare questions and information that will help you evaluate their capabilities and suitability for your project.

Ask about their quality control measures, industry experience, and customer support. Provide detailed information about your project requirements and ask if they have experience with similar projects.

Pay attention to how responsive the manufacturer is during initial contact. A prompt and thorough response is an indication of good customer service and a commitment to meeting your needs.

▶Follow-Up Communication
Once you’ve established contact with potential manufacturers, it’s important to maintain regular communication throughout the project.

Ask about their process for providing updates on progress and ensure that they assign a dedicated account manager to your project. Be prepared to provide feedback and ask questions as needed to ensure that the project stays on track.

Evaluate the manufacturer’s responsiveness and communication skills throughout the project. If issues arise, work with the manufacturer to find solutions and ensure that they remain committed to meeting your needs.

By maintaining open and effective communication with potential manufacturers, you can establish a strong partnership based on trust and shared goals.

China is the largest PCB manufacturing market. If you have PCB projects, you can definitely find a cost -effective production company in China. You can also contact us LSTPCB Manufacturing Company, we will quote you within 24 hours.

How to control the quality of pcb

12/13/2023 在： /通过：

Printed circuit boards are an integral part of electronic devices and are the core component that controls the entire device. pcb is used in a variety of applications including consumer electronics, automotive, aerospace, communications, medical devices and other industries.

Quality is the lifeblood of a product. pcb quality control processes, including visual inspection, functional testing and environmental testing. These processes are critical to detecting defects and ensuring that PCB assemblies function correctly and reliably.

In this article we will focus on the pcb component process, such as any control pcba quality, and emphasize the importance of quality control for the product. The details are as follows:

Basic Principles of Quality Control

IPC Standards
The IPC (Institute of Printed Circuits) sets industry standards for PCB design, assembly, and testing. IPC standards help businesses to maintain consistency and reliability in the final product.

Production Process Control
Production process control involves monitoring and controlling the entire production process to prevent defects and ensure consistency in the final product. This includes maintaining the temperature, humidity, and other environmental factors that may affect the quality of the final product.

Testing and Inspection
Testing and inspection are critical aspects of PCB assembly quality control. They involve using various methods such as automated optical inspection (AOI), X-ray inspection, and functional testing to detect and correct any issues that may arise during the assembly process.

PCB assembly quality control is a vital process that ensures that the final product meets the required performance standards and reliability. By implementing basic principles of quality control such as IPC standards, production process control, testing, and inspection, businesses can prevent defects and ensure consistency in the final product.

The importance of PCB quality control

The importance of PCB quality control is mainly reflected in the following aspects:

1. Ensure product performance: PCB is the core component of electronic equipment, its quality directly affects the performance of the entire product. Through strict quality control, you can ensure the quality of PCB manufacturing process, materials, layers, layout and wiring and other aspects of the quality, so as to ensure stable and reliable product performance.

2. Improve production efficiency: In the PCB production process, if there is a quality problem, it may lead to low production efficiency, or even need to rework or rework. Through quality control, we can find and solve the problem in time, avoid waste and delay in the production process, and improve production efficiency.

3. Reduce costs: PCB quality problems may lead to product damage, return or repair, etc., which will increase the cost of the enterprise. Through quality control, we can reduce the occurrence of these problems, thus reducing the cost of the enterprise.

4. Enhance corporate image: a strict quality control system can enhance the image and reputation of the enterprise, so that customers more trust and recognition of the enterprise’s products and services.

How to control the quality of pcb

First, the design stage: optimize PCB layout and circuitry

In order to improve the performance and quality of the PCB board, the design phase is crucial. Designers need to give full consideration to circuit layout, component selection and thermal management. In circuit design, factors such as electrical performance, signal integrity and electromagnetic compatibility should be given full attention. At the same time, the use of PCB design software, such as Altium Designer, Eagle, etc., can effectively reduce design errors, optimize the layout and improve design efficiency.

 

Second, the choice of materials: the selection of high-quality substrates and copper foils

The performance and quality of the PCB board depends largely on the materials used. In the manufacturing process, the selection of high-quality substrates and copper foil is critical. High-quality base materials can ensure the thermal performance and mechanical strength of the PCB, thus improving the reliability of the product. In addition, the selection of high-purity copper foil can improve conductivity, reduce resistance and improve circuit performance.

 

Third, the production process: strict control of process parameters

PCB production process process parameters to ensure the quality and performance of the PCB board is critical. These parameters include: copper sinking, etching, drilling, plating, screen printing, hot air leveling, etc.. Through strict control of these parameters, you can ensure that the size of the PCB board, line width, aperture, etc. to meet the design requirements, improve product reliability and performance.

 

Fourth, detection and testing: to ensure that products meet quality standards

For PCB board manufacturers, comprehensive inspection and testing of PCB boards produced is the key to ensure quality and performance. This includes visual inspection, automatic optical inspection (AOI), X-ray inspection, electrical testing and so on. Through these inspection and testing methods, problems in the production process can be effectively identified and eliminated to ensure that the product meets the design and quality standards.

 

Fifth. Quality management system: continuous terminal quality control and continuous improvement

To ensure the quality and performance of PCB boards, manufacturers should establish a comprehensive quality management system. Through the implementation of ISO 9001, ISO 14001, IATF 16949 and other international quality certification, not only to ensure that the company’s production processes and quality control system in line with international standards, but also to continuously improve and optimize the production process to improve product quality and performance. At the same time, regular training of employees to improve their skills and quality awareness is an important part of ensuring the quality and performance of PCB boards.

 

Sixth, environmental considerations: the implementation of green production strategy

In order to ensure the quality and performance of PCB boards at the same time, manufacturers should also pay attention to environmental protection, the implementation of green production strategies. This includes optimizing the production process, reduce waste and emissions of hazardous substances, the use of environmentally friendly materials, as well as the promotion of lead-free and halogen-free technologies. By implementing green production strategies, manufacturers can improve the environmental performance of their products while enhancing their corporate image and competitiveness.

Nine major quality problems and solutions of the PCB board

n the entire production process of the PCB circuit board, there are many quality control points. If it is not rigorous, the quality problem of the PCB line board is endless. This is also a headache, because there is only one of them, so big, so big, so big Most devices are not available. Next, introduce the 9 major quality problems and solutions of the PCB board.

1. [Layers]

Stratification is the difficulty of the boss of PCB, ranking first in common problems. The cause of it may be roughly as follows:
(1) Improper packaging or preservation, moisture;
(2) The preservation time is too long, exceeding the preservation period, and the PCB board is tide;
(3) Supplier’s materials or process issues;
(4) Design materials and copper surfaces are not well distributed.

 

2. [Poor weld]
Weldability is also one of the more serious issues, especially batch problems. The possible cause is plate surface pollution, oxidation, black nickel, nickel thick abnormalities, anti -welding SCUM (shadow), too long storage time, moisture absorption, PAD on the anti -welding, too thick (repair). The pollution and hygroscopic problems are relatively easy to solve, and other problems are more troublesome, and there is no way to find it through feeding inspection. At this time, it is necessary to pay attention to the process capacity and quality control plan of the PCB board factory. For anti -welding PAD and poor repairs, you need to understand the standards of PCB suppliers on the formulation of maintenance. Inspectors and inspectors have a good assessment system, and at the same time, it is clear that the dense area of the pads cannot be repaired.

 

3. [Board bending plates]
The reasons that may cause the plate bending plates are: supplier selection problems, abnormal production processes, poor control of heavy labor, improper transportation or storage, not strong enough design of the broken hole, and the differences in copper area of each layer are too large. In the last 2 points, the design of the design needs to be avoided in the early stage. At the same time, the PCB factory simulation stickers IR conditions can be required to test, so as not to occur in the back of the furnace. For some thin plates, you can need to add a wooden slurry plate to the packets when the packaging is used to avoid subsequent deformation. At the same time, add a fixture to prevent the device from overweighting the curved plate.

 

4, [scrape, dew copper]
Scratches and bronze are the defects that test the management system and execution of the PCB plant. This problem is not serious, but it will indeed bring quality concerns. Many PCB companies will say that this problem is difficult to improve. The author once promoted the improvement of scratches of many PCB factories, and found that many times it is not that it is not good, but whether to change it or not to change it. All PCB factories that seriously promote the project have improved significantly.

 

5. [Poor impedance]
Impedance is an important indicator of the radio frequency performance of the mobile phone board. Generally, the common problem is that the impedance differences between the PCB batches are relatively large. Since the current impedance test bar is generally on the side of the PCB, it will not ship with the board, so the supplier can pay the batch of impedance strips and test reports for each time they ship. Comparison data of the edge line diameter and the inner line diameter.

 

6. [BGA welding empty hole]
BGA welded cavities may cause poor main chip function, and may not be found in the test that hidden risks are high. So many patch factories now have X-Ray for inspection after the part. The cause of this kind of bad may occur is the residual liquid or impurities in the PCB hole, vaporization after high temperature, or poor laser hole type on the BGA pad. Therefore, many HDI boards now require electroplating pores or half -filled holes to avoid this problem.

 

7. [Foam/Show off for anti -welding]
Such problems are usually abnormal in the control of the PCB welding process, or the use of anti -welding ink is not suitable (cheap goods, non -chemical inks, not suitable for installing welded welds), or may be too high in patch and heavy work. To prevent batch problems, PCB suppliers need to formulate corresponding reliability test requirements and control them at different stages.

 

8. 【Poor Confucius】
Poor holes are mainly caused by insufficient technical capabilities of the PCB plant or simplified technology. Its manifestations are not full of plug holes. It may cause insufficient welding volume, short circuit with patch or assembly devices, and residual impurities in the hole. This problem can be found in the appearance inspection, so it can be controlled by the feeding inspection and requires the PCB plant to improve.

 

9. [Poor size]
There are many possible reasons for the poor size. It is easy to shrink in the PCB production process. Suppliers have adjusted the drilling program / graphics ratio / molding CNC program, which may cause problems such as biased bias and poor structural parts. Because it is difficult to check such problems, it can only be controlled by the supplier’s good process, so special attention needs to be paid to it when choosing the supplier.

Emphasizing quality control in PCB assembly is critical to improving product quality, reducing costs and protecting intellectual property. Therefore, we encourage our customers to select suppliers with strong quality control systems to ensure the reliability of their products.

At LST, we understand the importance of quality control in PCB assembly and are committed to providing our customers with high quality products. With our extensive experience in the field and state-of-the-art equipment, we can produce PCBs that meet the highest industry standards.

The working principle and application of Wireless charging

12/06/2023 在： /通过：

Charging mobile terminal devices is a necessary thing, and the most common charging method is to use a charger with a cable. But yes, with the rapid development of science and technology, wireless charging method has become the choice of more and more people. Wireless charging is convenient and quick, as long as the phone is elegantly placed on top of a small, coaster-like thing, without the need to connect the wire can be easily charged. Today we will focus on wireless charging.

What is wireless charging?

Wireless charging is actually using the principle of electromagnetic induction to generate a changing magnetic field in a changing electric field, and the changing magnetic field is generating a changing electric field in the receiving coil of the cell phone to charge the cell phone, which can be regarded as a separate transformer, putting the coil of the transmitter and the coil of the receiver into two separate devices, and when the power is fed into the coil of the transmitter, it will generate a magnetic field, which will detect the coil of the receiver and generate an electric current. coil, generating an electric current, and thus we have created a radio transmission system.

There are three main types of wireless charging technology:

1, electromagnetic induction type: the primary coil of a certain frequency of alternating current, through electromagnetic induction in the secondary coil to produce a certain current, so as to transfer the energy from the transmitting end to the receiving end.

2, magnetic field resonance: by the energy transmitting device, and energy receiving device, when the two devices adjusted to the same frequency, or resonate at a specific frequency, they can exchange each other’s energy.

3, radio wave type: microwave transmitting device and microwave receiving device consists of microwave, can be captured from the wall bounced back to the radio wave energy, with the load to make adjustments at the same time to maintain a stable DC voltage.

Advantages of wireless charging

1. Convenience: wireless charging technology eliminates the need for traditional charging cables, users do not need to plug and unplug the cable, just put the phone and other devices on the charging mat, which greatly improves the user’s convenience.

2. Environmental protection: wireless charging process does not involve plugging and unplugging action, thus reducing the wear and tear of the charging interface, thus extending the service life of the device. At the same time, this also reduces the generation of waste, which is conducive to environmental protection.

3. Safety: Wireless charging technology has no physical contact during the charging process, thus avoiding safety problems caused by poor contact or overcharging.

4. Universality: Wireless charging technology adopts a standardized scheme, so that devices of different brands and models can use the same wireless charging device as long as they support the same standard.

5. High efficiency: wireless charging technology adopts high efficiency charging mode, which can quickly provide power for devices and improve charging efficiency.

6. Energy-saving: Wireless charging technology adopts energy-saving technology, which can reduce energy consumption while ensuring charging efficiency.

7. Wide applicability: Wireless charging technology can be used not only for mobile devices such as cell phones, but also for transportation such as electric cars, electric bicycles and other devices that need to be charged.

8. Cost reduction: wireless charging technology can reduce the manufacturing cost and maintenance cost of charging equipment, improve the reliability and service life of the equipment.

9. Efficient management: wireless charging technology can realize remote monitoring and management, which is convenient for users to manage and maintain the charging equipment.

Application Scenarios of Wireless Charging

1. Mobile device charging: The initial application of wireless charging technology is to charge mobile devices, such as smartphones, tablets and so on. Users only need to put the mobile device on the wireless charging mat, no need to plug and unplug the cable, you can charge the device.

2. Electric vehicle charging: Electric vehicles are an important application area for wireless charging technology. Some electric cars have been equipped with wireless charging devices, users only need to park the vehicle on the wireless charging mat, the vehicle can be automatically charged.

3. Smart home: wireless charging technology can be applied in the field of smart home, such as smart speakers, smart lights and so on. Users only need to put the smart device on the wireless charging mat, it can provide power for the device.

4. Medical devices: Wireless charging technology can also be applied to the field of medical devices, such as wireless medical sensors, wireless medical monitoring devices. These devices can be placed in or near the human body to provide power to the device through wireless charging technology.

5. Industrial applications: wireless charging technology can also be used in the industrial field, such as wireless sensors, wireless remote control devices. These devices can work in harsh environments and provide power to the devices through wireless charging technology.

What is the TG value of PCB and how to choose?

12/05/2023 在： /通过：

It is well known that the base material polymer or glass) is changing from a glassy, solid, rigid state to a rubbery state when the temperature rises to a certain region, so the temperature at this point is called the glass transition temperature (Tg). In other words, Tg is the mechanical property that specifies the glass transition temperature, i.e., the maximum temperature at which the glass remains rigid.

TG in PCB boards means temperature resistance. the higher the Tg point, the higher the temperature requirement when pressing the board, the harder and more brittle the board will be, which will affect the quality of the mechanically drilled holes to a certain extent in the subsequent process.

PCB board TG value classification

Common board TG value can be roughly divided into three major categories:

TG130: general TG value of the board, temperature resistance of about 140 ℃, common such TG value of the board is Sheng Yi S1141 and Kingboard KB-6164F

TG150: Medium TG value plate, temperature resistance 150℃~170℃, common such TG value plate is SangYi S1141 150 and Kingboard KB-6165F.

TG170: Higher TG value boards, temperature resistance above 170℃, common such TG value boards are SangYi S1170 and Kingboard KB-6167F, the cost of higher TG value boards is also relatively high.

How to choose pcb with different TG values?

PCBs with different TG (glass transition temperature) have their own advantages and application scenarios, which one is the best to choose depends on the specific application needs. The following are some common TG PCBs and their characteristics.
1.FR-4(TG 130°C-180°C):FR-4 is one of the most common and widely used TG PCB circuit board materials. It has good mechanical strength, electrical properties and heat resistance.FR-4 is suitable for most general applications of electronic equipment and is relatively low cost.

2. High TG PCB ( TG 150°C-200°C):High TG PCBs have a higher glass transition temperature than regular FR-4, providing better stability and reliability in high temperature environments. They are suitable for applications that require operation in high temperature environments, such as automotive electronics, industrial controls and aerospace.

3. High Frequency TG PCBs: High Frequency TG PCBs are designed for high frequency signal transmission with excellent impedance control and signal integrity. These boards are typically made of low dielectric constant and low loss materials to ensure optimal signal transmission.

4. Metal Substrates:Metal Substrates are a special type of TG PCB that has a layer of metal (usually aluminum or copper) covering the substrate for heat dissipation and conductivity. Metal substrates are suitable for high power applications, LED lighting and power electronics where good thermal performance is required.

The best choice of TG PCB depends on your application needs, such as operating environment, signal requirements, temperature requirements, cost constraints, etc.

The basic characteristics and development prospects of FR4 pcb material

11/27/2023 在： /通过：

FR4 glass epoxy resin is currently the most used substrate in the pcb market. more than 80% of the pcb is manufactured with FR4, what is FR4, what are its characteristics, this article will focus on giving you an introduction.

FR4 is a glass fiber epoxy resin copper cladding board, it is based on chlorite, quartz sand, limestone, dolomite, boron calcium stone, boron magnesium stone six kinds of minerals as raw materials by high temperature melting, drawing, winding, weaving and other processes manufactured. The diameter of its monofilament for a few microns to more than two dozen microns, equivalent to a hair strand of 1/20 ~ 1/5, each bunch of fiber raw silk is composed of hundreds or even thousands of monofilaments.
The FR prefix refers to the flammability rating of the resin system used in the laminated composites that make up the substrate of a printed circuit board. The addition of bromine compounds to the resin produces flame retardant properties that are self-extinguishing and combustible.

FR4 Basic Characteristics

●Vertical laminar bending strength A: normal: E-1/150, 150±5℃≥340Mpa

●Parallel laminar impact strength (simply supported beam method): ≥230KJ/m

●Insulation resistance after water immersion (D-24/23): ≥5.0×108Ω

●Vertical laminar electrical strength (in 90±2℃ transformer oil, plate thickness 1mm): ≥14.2MV/m

●Parallel layer to the breakdown voltage (in 90 ± 2 ℃ transformer oil): ≥ 40KV

●Relative dielectric constant (50Hz): ≤5.5

●Relative dielectric constant (1MHz): ≤5.5

●Dielectric loss factor (50Hz): ≤0.04

●Dielectric loss factor (1MHz): ≤0.04

●Water absorption (D-24/23, plate thickness 1.6mm): ≤19mg

●Density: 1.70-1.90g/cm³.

●Flammability: FV0

What are the properties of FR4 substrates?

Flame Retardant

Chemicals used on materials to prevent or retard the spread of fire are known as flame retardants.FR4 substrates have excellent thermal, mechanical and electrical properties, making them perfect for a wide range of electronic applications. Flame retardant laminates and prepregs are very versatile, suitable for a variety of manufacturing procedures and produce predictable results.

Good Electrical Properties

The electrical properties of PCB materials are critical to signal integrity and impedance considerations. They determine how quickly an electrical signal can propagate through the material and how much charge it can retain in a given volume.

Low Moisture Absorption

Moisture absorption is the ability of a PCB material to resist absorbing water when immersed in water. It is given by the percentage increase in weight of the circuit board material due to water absorption under controlled conditions.FR4 material has a low moisture absorption of 0.10% after 24 hours of immersion in water.

 

Limitations of FR4 circuit board materials

FR4 has been used in printed circuit boards for many years. It is inexpensive and provides adequate electrical insulation. However, when FR4 is used in high-speed applications, the following problems may occur:

Insulation Stability
Although FR4 is a good insulator, it has its limitations when subjected to high power, high voltage or high heat. If certain limits are exceeded, the insulating properties of the material will deteriorate and they will begin to conduct electricity. This can lead to board failure.

Controlled Impedance
FR4 does not provide a uniform dielectric constant like high speed circuit board materials. As frequency increases, Dk changes. While high-speed materials have a dielectric constant tolerance of less than 2%, FR4 has a tolerance of up to 10%. the change in Dk in FR4 poses a challenge while maintaining the impedance value. Therefore, this material is not a preferred choice for controlling impedance boards.

Signal Loss
Signal loss is an important aspect of PCB design, especially in high-frequency applications.FR4 is not the best material for these applications because it has a larger Df (dissipation factor) than high-frequency materials.

FR4 Performance Classification

Standard F4
Baseline electric grade F4 epoxy glass provides the most economical, general purpose substrate for typical consumer electronics and digital circuit boards without pushing extreme frequency limits.

High Frequency F4
Multi-glass bodies like rf-35 control dielectric values below +/-0.05 across the microwave region. These tightly aligned low loss materials become critical to RF device integrity.

High Temperature F4
Through resin modification or bismaleimide-triazine blends, some FF4 formulations withstand temperatures above 230°C to meet the needs of aerospace and automotive electronics equipment.

Highly reliable F4
Isola’s “HR” family and Allen family 85N laminates utilize high resin content and glass weaving to punch holes in multilayers and are elastically rigid designed to resist crack propagation.

Development Prospect of FR-4 Copper Clad Laminate

FR-4 copper clad laminate is the core material of printed circuit boards, which is widely used in electronics, communications, computers, automotive, aerospace and other fields. With the development of 5G, Internet of Things, intelligent manufacturing and other emerging industries, FR-4 laminates have a very broad market outlook.

First of all, the development of 5G will promote the demand for FR-4 laminates, 5G communication technology requires superior high-frequency transmission performance, so the performance of FR-4 laminates also need to be improved. For example, the dielectric constant of the sheet needs to be increased and the dielectric loss of the sheet needs to be reduced. In addition, the miniaturization and lightweight of 5G equipment also put forward higher requirements for the performance of FR-4 boards, such as the need to optimize the thickness of the board. Therefore, with the rapid development of 5G in the future, FR-4 copper cladding board market demand growth prospects.

Secondly, the widespread application of the Internet of Things (IoT) will also drive the growth of FR-4 copper-clad laminates market demand. The Internet of Things requires higher performance indicators (such as high-frequency transmission, high-speed transmission, etc.), in addition to the miniaturization of the Internet of Things terminal equipment requires thinner and lighter FR-4 copper cladding boards, which will promote the FR-4 cladding board market demand continues to increase.

Again, the rapid development of intelligent manufacturing will have a positive impact on FR-4 laminate market demand. Intelligent manufacturing has become a national strategy, the transformation and upgrading of the manufacturing industry requires more intelligent equipment. These devices require high-speed transmission of high-frequency transmission and other performance indicators such as stringent FR-4 copper cladding boards, the market demand will also continue to increase.

FR4 has been widely used in electronic equipment for its high reliability, good processability, heat resistance and excellent electrical properties. Its dielectric constant and dielectric loss angle tangent and other electrical performance parameters are controlled with high precision, which can ensure stable signal transmission. In addition, FR4 sheet has good thermal stability and can remain stable in high-temperature environments, making it suitable for applications under various environmental conditions. Therefore, FR4PCB is an excellent electronic material, providing a strong guarantee for the performance and reliability of electronic equipment.