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What is 1st Article Inspection?

8 11 月, 2024

What is 1st Article Inspection For?

First Article Inspection (FAI) refers to the inspection of the first or several products produced at the beginning of production (such as every day, every shift or the beginning of each production batch) to confirm whether the production conditions (such as equipment, process, materials, environment, etc.) meet the technical and quality requirements. This is a preventive quality control measure designed to prevent batch defects by early detection of possible problems in the production process.

What is 1st Article Inspection?

The first inspection usually includes the following steps:

1. Preparation stage: clear inspection standards, inspection methods, inspection tools and equipment, and prepare relevant inspection records and forms.

2. Production preparation: Check whether the production equipment is in good condition, whether the process parameters are set correctly, and whether the raw materials or parts meet the requirements.

3. Production of the first piece: Start production according to the production plan, and make the first piece or the first few products as the first piece.

4. First inspection: Detailed inspection of the first product, including inspection of appearance, size, performance, function, etc., to ensure that the product meets the design requirements and quality standards.

5. Result judgment: According to the inspection results, determine whether the first piece is qualified. If qualified, mass production can continue; If it is not qualified, it is necessary to analyze the cause, adjust the production conditions, and re-make the first part for inspection until it is qualified.

6. Record and feedback: Record the results of the first inspection, and feedback the results to relevant departments and personnel in order to take timely measures to solve the problem.

Why Need to Perform a FAI?

◆ The first inspection in the production process is mainly to prevent the product from a batch of out-of-quality, repair, scrap. It is a means to control the product production process in advance, is an important method of product process quality control. It is an effective and essential method for enterprises to ensure product quality and improve economic efficiency.

◆ The first inspection is to find the factors affecting product quality in the production process as early as possible to prevent bad batch or scrap.

◆ The first piece can be entered into formal production after passing the inspection, mainly to prevent the occurrence of batch unqualified products.

◆ Long-term practical experience has proved that the first inspection system is an effective measure to detect problems as early as possible and prevent products from being scrapped in batches. Through the first piece inspection, it can be found that systematic causes such as severe wear of the fixture or installation positioning errors, poor accuracy of the measuring instrument, incorrect reading of the drawing, feeding or formulation errors exist, so that corrective or improvement measures can be taken to prevent the occurrence of batch nonconforming products.

What is 1st Article Inspection?

What Happens if a Component Passes or Fails the FAI?

If a component passes the FAI, full-scale production can proceed to next stage. Because knowing that the process yields parts that match design criteria. Meanwhile, it builds confidence and reduces the likelihood of future issues.

If a component fails, corrective action is necessary. This means process, parameters, or used tools, materials are not suitable or with poor quality. After modifications, a new FAI may be needed to verify the adjustments work as expected.

When Should a First Article Inspection Occur?

Knowing the right time for a 1st article inspection is crucial to avoid production issues and ensure highest quality. But when exactly should this process take place? Let me tell you:

  • Initial Production Run

Picture this – you’re ready to kick off a new product line or start manufacturing a brand-new part. This is the perfect time for an FAI. Performing it at this stage helps catch any potential problems right from the start. It’s like giving your process a test drive before you commit to full-scale production.

  • Process Changes

Changes are inevitable in manufacturing. Maybe there’s an upgrade to your equipment or you’re switching up the method used to produce parts. Any significant change to the process means it’s time for a new FAI. Why? Because even small adjustments can lead to unexpected differences in the final product.

  • Supplier Changes

If you decide to switch to a different supplier for critical components, you shouldn’t skip an FAI. Even if the new supplier promises the same specifications, differences in materials or production methods can impact the final product. An FAI here ensures that what you’re getting from the new supplier matches your quality expectations.

  • Design Modifications

Tweaking a design might seem minor, but it can change everything from part fit to performance. Any time there’s an update or redesign, running an FAI confirms that the modified product still aligns with the original quality standards.

What is the Difference Between PPAP and First Article Inspection?

You might hear the terms PPAP (Production Part Approval Process) and FAI thrown around in manufacturing discussions. While they share a goal of ensuring quality, they are different in their approach, scope, and where they are commonly used.

1. Industries and Common Use

    FAI is used across various industries, and it especially popular in fields like aerospace and defense. It’s typically a requirement when introducing a new part or process. PPAP, on the other hand, is most commonly linked to the automotive industry. It’s a standard method required by major automotive manufacturers to ensure that their suppliers can consistently meet production quality standards.

    2. Range and Detail

    FAI is about confirming that one specific piece meets all the design and specification requirements. The process involves checking the dimensions, materials, and other key aspects to ensure everything matches up before moving forward with full-scale production.

    PPAP, however, takes a broader approach. Instead of just focusing on one component, PPAP is like an in-depth audit of the entire production process. It includes elements like process flow diagrams, control plans, and even failure mode and effects analysis (FMEA). PPAP doesn’t just ask, “Does this part meet the specs?” but goes further to check if the entire production line can consistently produce parts that meet quality requirements over time. A PPAP file like as below:

    What is 1st Article Inspection?

    3. Level of Documentation

    FAI has its documentation, but it’s more straightforward. You get a detailed report of the inspected part, including dimensions and results from any tests performed. With PPAP, the documentation is more comprehensive and multi-layered. It often involves around 18 sheets, including a sample production run, process validation reports, and customer-specific requirements.

    First Article Inspection in Best Technology

    At Best Technology, we believe that FAI is more than a formality—it’s a guarantee of reliability and quality. So, we pay more attention to the first article inspection, from every step, every operator, every report. We have a 1st article inspection tester in our factory, for each prototype, we can finish the FAI inspection quickly and effectively.

    As an advanced PCB and PCBA manufacturer, we have more than 18 years experiences in this industry. We have served over 5000 customers with 98% satisfied comments. All of them are amazed with our one-stop service and quick delivery.

    What is hot bar soldering?

    7 11 月, 2024

    Hot bar soldering is a soldering method that uses heat and pressure to connect two or more materials together. The basic principle is to heat the surface of the material to a certain temperature to soften or melt it, and then apply a certain pressure to form a strong bond between the materials.

    What is the hot bar process?

    Hot bar soldering is a soldering method that applies pressure at a specific temperature. The process involves applying a pressure of 0.5 to 1.5N at a temperature above 200°C, so that the splitter brings the lead into contact with the soldering area and reaches the atomic distance, thereby generating an interatomic force to achieve the purpose of bonding.

    What is hot bar soldering?

    Specifically, during hot bar soldering, the temperature is usually above 200°C and the bonding strength is between 0.05 and 0.09N.

    Hot bar soldering is widely used in the field of microelectronic surface assembly technology, especially in connecting flexible circuit boards and rigid circuit boards. The stability and efficiency of this process are essential to ensure the good quality of the product.

    What temperature is hot bar soldering?

    The temperature range of hot bar soldering is usually between 200-400°C below the melting point of the material. Because within this temperature range, the metal surface can melt and fuse together with the help of pressure, forming a high-quality weld.

    Hot bar soldering is a method of joining two or more metal materials together by applying heat and pressure at the material joint, causing the material surface to melt and fuse together with the help of pressure.

    Temperature is a critical parameter in the hot bar soldering process because it directly affects the quality of the weld and the structure of the metal. If the temperature is too low, the molten pool may not form, resulting in an incomplete connection; while too high a temperature may cause the material to melt excessively and damage the metal structure.

    The temperature range of hot bar soldering is affected by many factors, including the properties of the metal, pressure, and welding time. The melting point of the metal is one of the most important parameters affecting the temperature selection, and welding is usually performed below the melting point of the material. Pressure and time also have a direct impact on the welding process because they have a direct impact on the contact and melting of the metal.

    In practical applications, choosing the right temperature requires a comprehensive consideration of multiple factors. In the production of multilayer boards, the hot pressing temperature is generally between 150℃ and 180℃, and the specific temperature can be adjusted according to the type of glue used and the characteristics of the board.

    In addition, the operating temperature range of high-frequency heat welding machines is generally between 100℃ and 300℃, and some special materials may require higher temperatures, up to 600℃.

    What is a hot bar?

    Hot pressing welding is a welding method that uses heat energy and pressure to melt and fuse two or more materials together at the contact surface. It is usually carried out at a temperature above 200°C and a certain pressure is applied to make the chopper bring the lead to contact the welding area and reach the atomic distance, thereby generating interatomic forces to achieve the purpose of bonding.

    Why use hot air soldering?

    The main reasons for using hot air soldering include its high efficiency, energy saving, environmental protection, high strength and wide application range.

    What is hot bar soldering?
    • High efficiency: hot air welding has a fast speed and can greatly improve production efficiency.
    • Energy saving: Compared with traditional welding methods, hot air welding consumes less energy and can reduce energy consumption.
    • Environmental protection: Hot air soldering does not require the use of additional substances such as chemical agents, does not produce harmful substances, has little pollution to the environment, and meets environmental protection requirements.
    • High strength: The weld of hot air soldering is uniform and strong, and the material after welding is not easy to deform.
    • Wide range of applications: Hot air soldering is suitable for various metal materials, as well as a variety of plastic materials.

    Is hot air soldering better than iron?

    Hot air soldering and soldering iron each have their own advantages and disadvantages. The choice of which soldering method depends on the specific application requirements.

    Advantages of hot air soldering

    • High efficiency: The efficiency of hot air soldering is usually higher than that of soldering iron, which is suitable for the removal and welding of large amounts of solder.
    • Temperature control: Hot air soldering can accurately control the welding process by adjusting the wind force and temperature, and is suitable for handling large-area welding tasks.
    • High safety: Hot air soldering guns generally use safe voltages and have anti-static functions, reducing the risk of electric shock and static damage to components.

    Advantages of soldering irons:

    What is hot bar soldering?
    • Accurate temperature control: The temperature control of soldering irons is more accurate, which is suitable for occasions that require precise welding, such as the welding of microelectronic components.
    • Flexible operation: The soldering iron is more flexible to operate and is suitable for delicate soldering work.
    • Low cost: The initial investment and operating cost of the soldering iron are usually low, which is suitable for users with limited budgets.

    Applicable scenarios:

    • Hot air soldering: Suitable for removing and soldering a large amount of solder, such as circuit board repair and large-area soldering during manufacturing.
    • Soldering iron: Suitable for occasions that require precise soldering, such as soldering of microelectronic components and delicate circuit board repair.

    In summary, hot air soldering and soldering iron have their own advantages and disadvantages, and which method to choose depends on the specific welding needs and application scenarios.

    How to use bar solder?

    The basic steps for using solder bar are as follows:

    • Preparation stage: First, put an appropriate amount of solder bar into the tin pot, connect the power supply and turn on the power switch, and adjust the temperature to about 250℃. Use the solder bar to tin the red heating tube until the tin surface covers the heating tube.
    • Melting process: When the tin bar begins to melt, new solder bar should be added in time until the molten tin surface reaches a suitable height. When there is no solder in the tin melting furnace, do not use the tin melting furnace to heat it.
    • Temperature control: The set temperature should not be too high to avoid accelerated oxidation of the tin surface. It is generally more appropriate to set it at around 300℃, and the specific temperature can be adjusted according to the use requirements.
    • Wave soldering process: During the wave soldering process, the content of the solder bar will continue to decrease. When the content is low to a certain extent, new solder bars should be added in time to maintain the height of the solder liquid and reduce the oxidation of the solder bar due to excessive tin wave drop.
    • Lead solder bar: If lead solder bar is used, it is necessary to remove impure copper and regularly check the solder composition in the soldering furnace.

    How does laser soldering work?

    Laser welding is an advanced welding method that uses a high-energy-density laser beam as a heat source to locally heat two or more metal or non-metal materials to a molten or partially molten state, and then quickly cools and solidifies to achieve connection.

    The working principle of laser welding can be divided into the following steps:

    • The laser generates a high-power laser beam: The high-power laser beam generated by the laser is focused on the surface of the material to be welded through a lens or other optical elements to form a small spot.
    • The spot has a strong thermal effect on the surface of the material: The spot has a strong thermal effect on the surface of the material, causing it to quickly heat up to the melting point or boiling point, forming a liquid or gaseous molten pool or vaporization hole.
    • The laser beam moves along a predetermined trajectory: The laser beam moves along a predetermined trajectory, causing the molten pool or vaporization hole to extend along the direction of the weld. At the same time, due to surface tension and capillary action, adjacent materials flow into the molten pool or vaporization hole to fill the gap.
    • The molten pool or vaporization hole cools and solidifies rapidly: After the laser beam is removed, the molten pool or vaporization hole cools and solidifies rapidly to form a uniform, dense, and high-strength weld.

    In short, hot pressing welding, as an efficient and reliable connection technology, plays an important role in modern industrial production. With the continuous advancement of science and technology, hot pressing welding technology will continue to develop and innovate to provide better connection solutions for the development of various industries.

    Gold Plated PCB Board: Why Use it?

    6 11 月, 2024

    During the PCB board manufacturing, there is an important process called surface treatment. This is mainly used to protect the board surface from oxidation, corrosion, and good electricity. Gold plating, also is a popular surface finishing method, which commonly used in the industry. As a professional PCB fabricator, here Best Team would like to introduce some key points about gold plating that customers always pay more attention to. Let’s keep reading!

    What is Gold Plating in PCB?

    Firstly, let’s know what is a gold plating. Gold plating on PCBs refers to a layer of gold applied over specific areas of a circuit board. This gold coating is typically applied on the connectors, pads, and edge contacts of a PCB to improve electrical conductivity and provide better resistance against wear and oxidation. Gold plating protects these sensitive areas, which are critical for the performance and reliability of the PCB.

    Gold Plated PCB Board: Why Use it?

    The principle of gold plating is to dissolve nickel and gold (commonly known as gold salt) in the chemical solution. And then the circuit board is immersed in the electroplating cylinder and the current is passed on the copper foil surface of the circuit board to generate nickel gold coating. Due to the electric nickel gold has good hardness, wear resistance, and not easy to oxidization, it is widely used in the electronics.

    Does Gold Plating Process Use Real Gold?

    ‌The gold plating in PCB is not really pure gold, but a gold alloy (has gold and some other metals in it). ‌

    In PCB manufacturing, gold-plating is usually not done using pure gold, but by compression and treatment of gold alloys. Such alloys often contain small amounts of metals such as silver, nickel, and copper to reduce costs and meet specific performance requirements.

    The role of gold plating in PCB is mainly to enhance electrical conductivity and chemical stability. Gold has good electrical conductivity and oxidation resistance, which can provide stable signal transmission and reliable connections in electronic devices. In addition, gold does not discolor or corrode, making it an ideal material for electronic applications.

    In general, there are two main gold-plating processes: electrolytic gold-plating and brush gold-plating. Electrolytic gold plating is the deposition of metal on the circuit board through chemical bath and electrolytic process, which has higher cost but better quality. Brush gold plating, by depositing metal particles onto a conductive substrate via electronic devices, is cheaper but of poorer quality.

    Why Use Gold in PCB?

    May somebody curious about why use gold in PCB? To make the PCB surface more beautiful? Let me tell you why.

    1. Improve electrical conductivity

    Metals such as gold have good electrical conductivity. Through gold plating, a metal conductive layer can be formed at the circuit connection of the PCB board, thus significantly improving the electrical conductivity of the circuit. This helps to reduce the resistance at the circuit connection, reduce signal loss.

    2. Prevent oxidation and corrosion

    The gold coating has excellent chemical stability and can resist oxidation and corrosion. This can protect the PCB board from the erosion of harmful substances in the external environment, such as humidity, salt spray, chemical gases, etc., thereby extending its service life.

    Gold Plated PCB Board: Why Use it?

    3. Improve welding performance

    Oxidized layer may be formed on the metal surface during welding, affecting welding quality. The gold coating can reduce the thickness of the surface oxide layer, thereby improving the reliability and robustness of the welding. In addition, gold plating can also provide better welding contact, reduce thermal stress during welding, and reduce the occurrence of welding defects.

    4. Enhance the appearance

    Gold plating can give the PCB surface metallic luster, improve the appearance texture and product grade, and increase the market competitiveness of the product. To be honest, gold appearance indeed gives a better appearance.

    5. Meet specific needs

    In some high-end electronic products, there are higher requirements for the electrical conductivity, corrosion resistance, welding performance and appearance texture of PCB boards. Gold plating, as an effective surface treatment technology, can meet these specific needs.

    6. Meet welding quality challenges

    With the improvement of integration of electronic products, IC feet are becoming more and more dense, and traditional vertical tin injection technology is difficult to meet the welding challenges of thin pads. Gold plating technology can provide better welding performance and reliability, and reduce the occurrence of welding quality problems such as virtual welding.

    How Thick is Gold Plating on Circuit Boards?

    The thickness of gold plating on PCBs depends on the type and application. Generally, PCB gold plating thickness ranges from 0.1-1.27um. For standard PCBs, a gold layer thickness of 0.03 to 0.05 microns is common, especially for immersion gold. However, thicker plating is applied for connectors or contacts exposed to frequent wear and tear, as these areas need more protection.

    Hard gold, used for high-wear applications like edge connectors, typically has a greater thickness than immersion gold. The thickness is carefully controlled because too thin a layer might fail to provide effective protection, while an excessively thick layer could lead to wasted materials and unnecessary expense. The goal is to strike a balance that delivers durability without incurring excessive costs.

    What is the Difference Between Immersion Gold and Hard Gold PCB?

    Hard gold plating ‌is by electroplating, so that the gold particles are attached to the ‌PCB board, so it is also called electric gold. Because of its strong adhesion, hard gold plating is also called hard gold, which is often used for ‌ memory bar ‌ gold finger and other parts that need wear-resistant.

    ‌Immersion gold ‌ is through the ‌ chemical reaction, the gold particles crystallization and attached to the PCB ‌ pad, so it is also known as ‌ soft gold. Due to the weak adhesion, the sinking gold is mainly used for the surface treatment of the pad, and the weldability is good. The difference between hard gold plating and immersion gold are including:

    • Color: Immersion gold is more yellow, while gold plating is more white.
    • Crystal structure: Immersion gold has a denser crystal structure.
    • Thickness: Immersion gold has a thicker layer of gold.
    • Wear resistance: Gold plating is harder and more resistant to wear and tear.
    • Solderability: Immersion gold is easier to solder.
    • Short circuits: Gold plating is more likely to cause short circuits.
    • Oxidation resistance: Immersion gold is less prone to oxidation.
    • Cost: Immersion gold is more expensive.
    • Deposition process: Gold plating uses an external electric current, while immersion gold is a chemical process.
    • Suitability: Gold plating is better for environments with high mechanical stress, while immersion gold is better for movable contacts.

    PCB Applications of Gold Plating

    Gold-plated PCBs are popular in industries where reliability and durability are essential. Some typical applications include:

    • Aerospace and Defense
    • Medical Devices
    • Telecommunications
    • Consumer Electronics
    • High power electronics
    • High current electronics
    • Low voltage digital logic electronics

    As a PCB and PCBA manufacturer, we provide various surface treatment options for customers, including: ENIG, ENEPIG, OSP, HASL-LF, Immersion gold, hard gold (up to 50u’’). We offer customized PCB service tailored to customer’s requirements, we will try our best to meet the demands of surface treatment. Welcome to contact us if you have any questions.

    What is a PCB antenna? How does it work?

    5 11 月, 2024

    PCB antennas are crucial in today’s compact wireless devices. These antennas are directly integrated into the PCB board, providing an efficient way to transmit and receive signals. They have become more and more important in IoT devices, smartphones, and many other electronic products.

    What is a PCB Antenna?

    A PCB antenna is an antenna built directly onto the printed circuit board, often as a conductive trace or embedded component. By integrating it directly onto the PCB, the antenna becomes a seamless part of the overall design, eliminating the need for separate antennas. The design principle of PCB antenna is based on electromagnetic field theory. By arranging a specific metal conductor pattern on the PCB board, an effective electromagnetic radiation and receiving structure can be formed, so as to achieve the transmission and reception of wireless signals.

    What is a PCB antenna? How does it work?

    This antenna uses PCB as the medium, through the PCB process to achieve, no need to assemble the antenna separately, testing and use are very convenient. PCB antenna can be directly integrated on the circuit board, easy to touch and damage, and easy to assemble.

    PCB Antenna Types

    PCB antennas come in different types, each suited to specific applications and requirements. The most common types include:

    • Monopole Antennas

    These antennas are simple, consisting of a single conductor. They’re straightforward to design and offer decent performance for applications with limited space. Monopole antennas are ideal for Bluetooth and Wi-Fi applications, where simplicity is needed without compromising basic functionality.

    • Dipole Antennas

    Known for their balanced design, dipole antennas use two conductors, often resulting in improved radiation patterns. They are commonly used in environments where the antenna needs to work effectively in multiple directions. Dipole antennas are popular in high-frequency applications.

    • Inverted-F Antennas (IFA)

    This type features a ground plane and a radiating element shaped like an “F.” IFAs are compact and provide a stable, omnidirectional pattern, making them suitable for Wi-Fi and cellular applications. The structure of IFA antennas helps achieve good efficiency even in confined spaces.

    • Patch Antennas

    These antennas are flat and rectangular, making them excellent for devices with strict space limitations. Often used in GPS and RFID applications, patch antennas offer directional radiation patterns, allowing them to focus energy toward specific areas, enhancing range and strength.

    • Slot Antennas

    Slot antennas consist of a slot cut out of a conductive surface, with electromagnetic fields radiating from the slot. They are typically more directional, so they are suitable for specific point-to-point applications or where the signal needs to be targeted.

    What is the Frequency Range of a PCB Antenna?

    The frequency range of a PCB antenna depends on the design and intended application. Most PCB antennas operate within common wireless communication bands, such as 2.4 GHz for Wi-Fi, Bluetooth, and other short-range communications. However, they can be designed for various ranges, including sub-1 GHz bands (for long-range IoT applications) and frequencies as high as 5 GHz for Wi-Fi 6 and other high-speed networks.

    Higher frequencies typically require smaller antennas, which aligns well with compact devices but may also affect range. Low-frequency antennas, on the other hand, are larger but provide greater coverage and are less affected by obstacles.

    PCB antenna’s Basic Formulas

    1. Wavelength Calculation

    The wavelength (λ) of the signal is an essential parameter in designing antennas, especially for determining the length of a PCB trace antenna.

    What is a PCB antenna? How does it work?

    Where:

    c = Speed of light (approximately 3×10^8m/s)

    f = Frequency in Hz

    For example, at 2.4 GHz (a common frequency for Wi-Fi and Bluetooth), the wavelength is around 12.5 cm.

    2. Length of a Monopole Antenna

    For a monopole antenna on a PCB, the length (L) of the antenna is typically set to one-quarter of the wavelength. This is known as a quarter-wave monopole antenna, which is commonly used in PCB designs.

    What is a PCB antenna? How does it work?

    This length provides a good balance of efficiency and compact size.

    3. Length of a Dipole Antenna

    A dipole antenna is usually designed to have a length of half the wavelength. The total length L for a dipole is:

    What is a PCB antenna? How does it work?

    Each “arm” of the dipole would then be a quarter-wavelength. This structure is well-suited for many applications due to its balanced design.

    4. Inverted-F Antenna (IFA) Length Calculation

    For an Inverted-F Antenna, the length of the main resonant arm is usually close to a quarter of the wavelength. This helps the IFA to maintain a compact form while still achieving effective performance:

    What is a PCB antenna? How does it work?

    Since IFAs often include a grounding element, they may be slightly shorter than traditional quarter-wave monopoles.

    5. Impedance Matching

    The impedance (Z) of the antenna needs to match the transmission line (typically 50 ohms) to maximize power transfer. For a basic dipole or monopole antenna, the impedance can be approximated with empirical formulas. For instance, a free-space dipole impedance is around 73 ohms, but this value changes on a PCB.

    To achieve matching, adjustments can be made by changing the length or width of the antenna trace or by using matching networks with inductors or capacitors.

    6. Resonant Frequency Calculation

    The resonant frequency (f) of a PCB trace antenna depends on its physical length. Rearranging the wavelength formula allows you to solve for f if you know the length:

    What is a PCB antenna? How does it work?

    Where L would typically be one-quarter of the wavelength for a monopole or half for a dipole.

    7. Effective Dielectric Constant Adjustments

    PCB antennas are affected by the PCB material’s dielectric constant (ϵr). This changes the effective wavelength (λ):

    What is a PCB antenna? How does it work?

    Using this adjusted wavelength improves accuracy in trace length calculations for PCB antennas, especially when working with substrates with a high dielectric constant.

    8. Bandwidth Calculation

    The bandwidth of a PCB antenna can be approximated using the Quality Factor (Q) of the antenna:

    What is a PCB antenna? How does it work?

    Where Q is influenced by factors such as antenna length, material, and layout. Lower Q values usually provide broader bandwidth, which can be achieved through specific design choices like wider traces or shorter antennas.

    9. Gain Estimation

    The gain of a PCB antenna depends on its radiation pattern and efficiency. Although gain is typically measured rather than calculated, some estimates can be made based on the type of antenna and its efficiency. For simple PCB antennas, a rough gain value might range from 0 dBi (isotropic) for omnidirectional designs to 3–5 dBi for directional designs.

    Are PCB Antennas Directional?

    PCB antennas can be directional or omnidirectional, depending on their type and design. Directional antennas focus the energy in a specific direction, which increases range in that direction while reducing it in others. Omnidirectional antennas, in contrast, distribute the signal evenly in all directions, which is beneficial for applications where the device orientation may vary.

    Patch antennas and slot antennas are generally more directional, suitable for point-to-point communication or when a targeted signal path is needed. Monopole and dipole antennas, however, are typically omnidirectional, making them ideal for devices like smartphones and IoT gadgets, where a consistent signal is required from various angles.

    The choice between directional and omnidirectional antennas should align with the specific needs of the application. For example, in a warehouse, an omnidirectional antenna might be preferred for broad coverage, while a directional antenna could be beneficial for a remote control application.

    What Are the Applications of PCB Antenna?

    PCB antennas are used in a wide range of applications, including:

    • Consumer Electronics: PCB antennas are essential in smartphones, tablets, and laptops for Wi-Fi, Bluetooth, and cellular connectivity.
    • IoT Devices: Many IoT devices use PCB antennas for wireless data transmission, making them integral in smart homes, agriculture, and industrial monitoring.
    • Automotive: In vehicles, PCB antennas enable GPS, remote keyless entry, and other connectivity features, enhancing both functionality and user experience.
    • Medical Devices: PCB antennas are used in medical equipment for wireless communication, which enables real-time monitoring and diagnostics.
    • Wearables: PCB antennas are commonly found in wearable tech like fitness trackers and smartwatches, where compactness is a priority.
    • Industrial Equipment: Many industrial machines rely on PCB antennas for remote monitoring and control, helping to streamline operations and improve efficiency.

    When choosing a PCB antenna, consider the application requirements, including size constraints, frequency range, and directional needs. PCB antennas bring numerous advantages to electronics, from consumer gadgets to industrial equipment. With the right antenna, you can achieve reliable wireless communication, keeping your designs efficient and effective in today’s connected world.

    What is Silkscreen on PCB?

    4 11 月, 2024

    If you’ve ever taken a close look at a printed circuit board (PCB), you might have noticed small text, symbols, and lines on the surface. These aren’t just for decoration — they make up the PCB’s silkscreen layer, which plays a key role in making the board readable and easy to assemble. Think of silkscreen as a guiding map that helps technicians identify components and connections quickly. From component labels to polarity indicators, this layer is a simple yet invaluable part of any well-designed PCB. Let’s dive into what silkscreening is, why it’s so useful, and what you need to know about its colors, materials, and application methods.

    What is Silkscreen on PCB?

    What is a Silkscreen on a PCB?

    Silkscreen is a layer of ink applied to the PCB’s surface. Typically, you’ll find it on the top side, although it can also be placed on the bottom. Screen silkscreen is usually used to indicate useful information on the PCB board, which can help the user in the assembly process, and is used to mark the component value, part number, polarity and other information, but also contains the version, manufacturer and other information. You’ll often see labels, symbols, and small icons that guide people assembling or repairing the board. In a busy PCB layout, the silkscreen is a roadmap for where everything goes, helping avoid mix-ups and reducing assembly time.

    What is Silkscreen on PCB?

    What is the Purpose of Silkscreen?

    The silkscreen layer’s primary purpose is to add clarity. By showing clear labels for components, it reduces the chance of error during assembly. When it’s time to troubleshoot, silkscreen also makes life easier by letting technicians locate parts quickly. Silkscreen may include warnings, brand logos, or model names, all helping to make the board more informative. Essentially, it saves time, improves accuracy, and simplifies the process from start to finish.

    Silkscreen Information Include on PCB

    Silkscreen can be letters, numbers, text. PCB screen printing is done during the PCB manufacturing process, but is used for the PCB assembly process step. Here are some common information that can be silkscreened.

    1. Polarity reference sign

    2. Determine the test point

    3. Component bit number reference mark

    4. Component boundary

    5, component pin mark

    6. Unique identification number for each board

    7. Company logo

    8. Version number

    9. Date code

    10, Manufacturer’s logo, serial number, lot number

    11. Warning symbols

    12. Regulatory marks

    Regulatory marks are used to indicate that a design has passed inspection or complies with specific regulations. RoHS, FCC, CE and e-waste disposal marks are commonly found on consumer and commercial products that have passed relevant inspections.

    What is Silkscreen on PCB?

    If another mark is seen on a design that has been inspected for safety: the UL mark, this mark indicates that the design was manufactured and assembled by a UL-certified manufacturer according to the UL796 and UL94 standards.

    What are the Colors of PCB Silkscreen?

    The color of silkscreen is chosen based on readability. White is the most common choice, especially on boards with a green soldermask, because it has a very good readability. And it is a public color and is more friendly to manufacture.

    In addition, other colors such as yellow, red, black are also commonly used in the initial stage of PCB board design, pink screen printing is a favorite color of some PCB Layout, but it is usually not recommended to use this color, because it has special characteristics and is not friendly to the manufacturing process.

    PCB Silkscreen Symbol

    Silkscreen symbols represent various components on the board, making it easier to find specific parts and identify their functions. For instance, “R” stands for resistors, “C” for capacitors, and “U” for integrated circuits. Symbols also show component orientation and polarity, which is crucial for accuracy in assembly. Well-organized symbols on the silkscreen save time and effort, especially during maintenance, as they allow technicians to pinpoint components instantly.

    What is the Difference Between Silkscreen and Solder Mask?

    Solder mask is a green or other color layer coated on the circuit board, which can play a role in protecting the board. Because there are usually many wires and components on the surface of the circuit board, it is easy to have problems such as short circuit or virtual welding during the welding process, which will lead to damage to the circuit board. Solder resistance layer can effectively avoid the occurrence of this problem. At the same time, the solder resistance layer can also improve the corrosion resistance and mechanical strength of the circuit board.

    Solder mask and silkscreen are both coated on the circuit board, but their roles are different. The solder resistance layer is mainly used to protect the circuit board from welding problems, and the screen printing is used to identify the components and related information on the circuit board. In addition, the solder mask is usually green or other bright colors, and the screen printing is usually white or other light colors for easy identification.

    What is the Screen Printing Method of PCB?

    There are totally three ways to print silkscreen on a PCB surface, manual screen printing, LPI, and DLP. Let me introduce them for you:

    1. Manual screen printing

    Do this on the PCB when the registration tolerance is 0.005 inches or the line width is greater than 0.007 inches. Perform manual screen printing using a mold containing text and traces. Traces are made of nylon. The ink is directed to the layer or laminate by stenciling. Next, the ink is cured in a baking oven. This is one of the easy ways to create a silk-screen layer, and it also supports large fonts. Perfecting the art can take years.

    2. Liquid Photo Imaging (LPI):

    This method is used to screen print threads larger than 4 million. The process of LPI is almost the same as the application of solder mask. In this method, however, the laminate is coated with epoxy resin and then placed under ultraviolet light. The plate is cured and then developed. This method ensures greater accuracy than manual screen printing.

    LPI uses white, which requires more ink than the other two types of screen printing. Such prints take a long time to set up.

    3. Direct Legend Printing (DLP):

    This is one of the other three processes that is expensive. In this process, an inkjet projector and acrylic ink will be used. The ink is applied to the PCB using CAD software. The ink is then exposed to ultraviolet light. Acrylic links are not suitable for PCBS that may have a silver surface.

    How Thick is the Silkscreen on a PCB?

    Silkscreen thickness is usually about 0.02 mm. This thin layer is enough to make the markings visible without interfering with the board’s layout or operation. The thinness is key because it keeps the board easy to handle without any obstruction or interference, but it’s thick enough that it won’t wear off easily during normal use.

    Best Technology highly specialized not only in quick-turn PCB prototype and PCB assembly, but also medium and small volume PCB fabrication. We can provide silkscreen on your PCBs for you with various colors, and we will try our best to meet the demands of silkscreen. If you have any questions, please feel free to contact us, we will be happy to help you.

    What is an AOI in PCB?

    1 11 月, 2024

    AOI, or Automated Optical Inspection, is a process in PCB manufacturing that utilizes advanced imaging technology to inspect PCBs for potential defects. During the inspection, cameras capture detailed images of the PCB at different stages, comparing them against predefined standards to ensure every component is correctly placed and connected. AOI serves as a crucial step, helping detect manufacturing flaws that could lead to functional issues.

    What is an AOI Machine in PCB?

    AOI machine is a kind of inspection equipment based on optical principle, mainly used to detect various defects on a PCB board. The AOI device automatically scans the PCB through a high-definition CCD camera, acquires images, and compares the tested solder joints with qualified parameters in the database. After image processing, the defects on the PCB are checked, and the defects are displayed through the display or automatic signs for repair personnel to correct.

    AOI detection is mainly composed of light source and its control subsystem, digital imaging and its control subsystem (including CCD/CMOS camera, image acquisition), image scanning motion mechanism and its control subsystem, image processing and optimization subsystem, image feature recognition and defect recognition subsystem, HMI and main control subsystem. These subsystems work together to scan the PCB and obtain the PCB image by controlling the light source, digital imaging, scanning and other subsystems, and then register the processed PCB image with the PCB standard image, extract features and compare and analyze the processed PCB image to determine whether the PCB has defects and the type of defects, and identify the location of defects.

    What is the Basic Principle of AOI?

    The principle behind AOI is quite straightforward: it illuminates the PCB through the light source, uses the optical lens to collect the reflected light of the PCB into the computer, and analyzes the color difference or gray ratio of the PCB information through the computer software, so as to judge the solder paste printing on the PCB, component placement, solder joint welding quality and so on. The AOI system can also analyze and count the defects to provide a basis for adjusting the process parameters of the manufacturing process.

    In another word, it relies on optical imaging and pattern recognition to detect defects. AOI machines are programmed with reference images of a perfect PCB layout. They then scan each PCB, capturing images and comparing them pixel-by-pixel to the reference model. Variations between the scanned image and the reference indicate potential defects, prompting the machine to flag these areas for further review.

    What are the Benefits of an AOI Machine?

    1. Accuracy in Detection

    AOI machines can identify defects that might be overlooked by manual inspection. The precision with which they analyze each PCB ensures high-quality output, reducing errors in the final product.

    2. Speed and Efficiency

    Automated inspection greatly speeds up the inspection process, especially valuable in large-scale manufacturing. With AOI, hundreds of PCBs can be checked in a fraction of the time required for manual inspection.

    3. Cost Reduction

    Early detection of defects prevents costly rework or scrap, saving both time and resources. By addressing issues during the early stages, AOI contributes to a smoother production process.

    4. Consistency and Reliability

    Unlike human inspection, which can vary, AOI provides consistent results every time. It applies the same criteria to every PCB, ensuring uniformity and quality across all batches.

    5. Enhanced Quality Control

    In a competitive market, high-quality products build trust with clients. AOI enables manufacturers to deliver high-standard PCBs, maintaining quality and reducing potential returns.

    What Kinds of Defects Can Be Checked During AOI?

    1. Soldering Issues

    AOI machines are highly effective in identifying soldering defects, such as insufficient solder, excess solder, or bridging, which can interfere with connectivity.

    2. Misalignment of Components

    AOI can detect misaligned components or misplaced parts, which might cause issues in functionality or even physical interference on the PCB.

    3. Component Presence and Orientation

    The machine checks if all components are present and correctly oriented. Missing or rotated parts can lead to non-functioning circuits.

    4. Short Circuits and Opens

    AOI identifies unwanted connections (shorts) and incomplete circuits (opens), ensuring each connection is accurate and functional.

    5. Surface Defects

    Surface issues, including scratches, contamination, or other irregularities, are also detectable through AOI, contributing to the visual quality of the board.

    6. Polarity and Value Verification

    Some AOI systems can check component polarity and values, confirming that each component matches the required specifications for the PCB design.

    AOI Applications

    1. Consumer Electronics Manufacturing

    Given the high volume of consumer electronics, AOI’s speed and accuracy are essential for maintaining efficiency without sacrificing quality. It is used for inspecting products like smartphones, laptops, and household appliances.

    2. Automotive Industry

    In automotive electronics, reliability is critical. AOI helps ensure that safety and performance-related components are defect-free, such as sensors, control units, and in-car entertainment systems.

    3. Medical Devices

    Medical equipment relies on precision and reliability. AOI in PCB inspection for medical devices ensures that these life-saving tools meet strict standards, minimizing risks in critical applications.

    4. Aerospace and Defense

    For aerospace and defense, where reliability and durability are paramount, AOI supports quality assurance in sensitive equipment, such as navigation systems and communication devices.

    5. Telecommunications

    In telecommunications, AOI assists in inspecting high-frequency PCBs, ensuring that communication devices remain operational and effective over long periods.

    To ensure high quality of PCBA, Best Technology equipped with 3D online AOI to detect PCB defectives from all aspects. Contact us if you have any questions.

    How to Reworking a PCB? PCB Rework and Repair Guide

    31 10 月, 2024

    PCB rework is a delicate yet vital process for restoring functionality to circuit boards with flaws or damages. It involves methodically removing, replacing, or modifying components to correct issues. Whether it’s due to design alterations, assembly errors, or minor repairs, PCB rework can save costs and prevent discarding entire units

    What is the Process of PCB Rework?

    The process of PCB rework generally follows a series of careful steps. Technicians start by inspecting the board to identify the defective areas. For rework, precise tools like soldering irons, hot air rework stations, or BGA rework machines are typically used.

    Once heated, damaged or defective components are removed. A flux application ensures that the solder flows cleanly, which reduces the risk of bridging or insufficient connections. The next step is carefully placing a new component in place, using a microscope to ensure accuracy, particularly for small parts like surface-mount components. Finally, the connections are resoldered, and the board undergoes cleaning and testing.

    What is the Difference Between Repair and Rework in PCB?

    PCB repair and rework, though closely related, serve unique purposes within electronics manufacturing and servicing. Rework refers specifically to correcting issues in a PCB due to assembly errors or modifications required before the board is shipped to the customer. This process should be operated very carefully, including during removing, adjusting, or replacing components. For instance, rework might be needed if components were placed incorrectly, solder joints are weak, or the board has minor assembly defects.

    Repair, however, addresses boards that have become faulty or non-functional after use. Repair focuses on bringing a board back to working condition, whether due to physical damage, such as broken traces or burnt components, or due to environmental factors like corrosion. While rework ensures the board meets its initial design intent, repair aims to recover a board’s functionality after it has failed. Both repair and rework require precise techniques and skilled technicians, but repair can be more complex due to the nature of post-production or operational damages.

    In summary:

    • Rework: Fixing pre-delivery assembly issues to align the board with its intended design.
    • Repair: Restoring functionality to a damaged or non-functional board, often due to wear, damage, or environmental exposure.

    How Many Times Can You Rework a PCB?

    The number of rework attempts a PCB can safely endure depends on factors like the materials used in the board, the board’s structure (e.g., number of layers), and the rework methods applied. Typically, each rework cycle subjects the board to a heating process, which can wear down solder joints and laminate strength over time. For most PCBs, rework should be limited to two or three cycles to avoid degradation, as repeated heating can lead to pad lifting, warping, or delamination of the substrate, especially with multi-layer boards.

    Multilayer PCBs with multiple embedded connections are particularly sensitive, as excessive heating can damage internal layers. High-temperature cycles weaken solder joints, increasing the risk of electrical faults. Some high-quality boards, particularly those designed for critical applications like aerospace or medical devices, may tolerate additional rework if built with durable materials, but general guidance suggests minimal rework attempts. Careful planning and accurate diagnostics are essential for minimizing rework cycles, ensuring the board’s lifespan is preserved.

    Can a Damaged PCB Be Repaired?

    Yes, in many cases, a damaged PCB can be repaired.

    It depends on the type and extent of the damage. For example, broken traces, lifted pads, and minor component failures are often fixable. Using epoxy, technicians can repair lifted pads, while trace repair kits can restore broken connections. However, severe burns or extensive damage to multiple layers can make repairs impractical or costly. The best approach is to assess each situation individually and determine if repair is viable.

    What Wire is Best for PCB Rework?

    Using the right wire during PCB rework is crucial for achieving reliable connections. For rework, thin, lead-free solder wire with a flux core is often recommended. A wire diameter of 0.5mm to 0.8mm provides better control and precision, making it suitable for both small and large components. Lead-free solder is preferred in many industries due to environmental regulations, but it requires higher temperatures than traditional lead-based solders, so it’s essential to have proper temperature control.

    Flux-core solder wire is essential as it allows for smoother, more reliable connections by promoting better solder flow and reducing oxidation at solder joints. Rosin-core flux is commonly used because it provides a strong bond and requires minimal cleaning. Additionally, if jumper wires are needed to bridge broken traces, insulated 30 AWG wire is ideal due to its fine gauge.

    What is the IPC Standard for PCB Rework?

    The IPC standards for PCB rework and repair are widely recognized and adhered to within the electronics industry to ensure quality and reliability. IPC-7711 and IPC-7721 specifically address rework, modification, and repair of printed circuit boards.

    • IPC-7711 provides guidelines for reworking and modifying electronic assemblies. This includes instructions on tools, temperature control, and safety practices necessary for removing and replacing components while preserving the board’s structure. It offers details on soldering and desoldering techniques that ensure high-quality connections after rework.
    • IPC-7721 focuses on the repair aspect, covering methods for handling damaged components and structural faults like broken traces, lifted pads, and substrate repair. This standard is critical for technicians performing repairs, as it outlines best practices for restoring physical and electrical integrity without compromising board function.

    What is the Main Cause of PCB Failure?

    PCB failures may cause from a variety of factors, with design flaws, manufacturing errors, and environmental stresses among the primary culprits. Here’s a closer look at some of the main causes:

    • Design Flaws: Poorly optimized PCB layouts can lead to issues like excessive heat buildup, inadequate trace width for current capacity, or improper component spacing.
    • Manufacturing Errors: Mistakes during the assembly process, such as improper soldering temperatures or placement inaccuracies, can lead to weak solder joints or misaligned components. These issues may not be apparent initially but can result in premature board failure.
    • Environmental Stress: PCBs exposed to extreme temperatures, humidity, or corrosive environments are at risk of damage. Moisture can cause short circuits or corrosion on solder joints and traces, while high temperatures may warp the board or degrade the substrate. Boards used in outdoor or industrial settings are especially vulnerable.
    • Electrostatic Discharge (ESD): Sensitive components can fail if exposed to static electricity.
    • Aging and Wear: Over time, boards and components naturally wear out. Solder joints may crack, components degrade, and thermal cycles lead to material fatigue.

    If your PCB or PCBA can’t work, and don’t know where is the problem. You can contact Best Team to ask for help, we are professional in this industry.

    What is Laser Direct Imaging in PCB Manufacturing?

    30 10 月, 2024

    ‌What is Laser Direct Imaging?

    Laser Direct Imaging (LDI) is a technology that uses a laser beam emitted by an ultraviolet laser to image directly on a PCB (printed circuit board). Compared to traditional exposure techniques, LDI has higher image quality, precision traces and real-time adjustment.

    The LDI technology achieves pattern transfer by projecting the line image directly onto the PCB coated with photoresist through the laser beam emitted by the laser diode. This method eliminates the use of negatives in the traditional exposure process, reduces the time and cost of loading and unloading negatives, and avoids deviations caused by negative growing. The image resolution of LDI technology is high, and the fine wire can reach about 20um, which is suitable for the production of fine wire and improves the yield of PCB production.

    What is Laser Direct Imaging in PCB Manufacturing?

    Working Principle of LDI Technology

    The principle of laser imaging is to acquire and present images based on the characteristics of laser beam. As we know, a laser is a highly focused, high-brightness, monochromatic beam that can therefore produce high-quality images. The laser imaging system mainly consists of laser, lens, scanning device and receiver. The laser is used to generate the laser beam, the lens is used to focus the beam, the scanning device is used to change the path of the beam on the object, and the receiver is used to receive the light signal and convert it into an image.

    In the imaging process, the laser beam is focused from the laser through the lens, and then the path of the beam on the object is controlled by the scanning device. When the laser beam hits the surface of an object, it interacts with the surface. This interaction causes light to scatter and reflect, with scattered light diffusing in different directions and reflected light remaining in its original direction of propagation. The receiver receives the light scattered and reflected by the object and converts it into an electrical signal. The receiver converts the signal into a digital image signal, which is then processed and displayed on the screen to form an image. In the processing process, the received signal can be filtered, amplified and other operations to improve the quality and clarity of the image.

    What is Laser Direct Imaging in PCB Manufacturing?

    As PCB manufacturing processes continue to advance, LDI technology is also evolving. At present, the mainstream light source in the industry is the 405nm laser diode produced by Nichiya, Panasonic, and it is expected that the optical power requirements for exposure will be further improved in the future, and the optical power of a single device may develop to 100W. Nowadays, LDI technology is not only used in PCB manufacturing process, but also in high-end applications like medical imaging, industrial detection, remote sensing.

    Advantages of Laser Direct Imaging Over Photo Exposure

    The advantages of laser direct imaging (LDI) compared with traditional exposure machines mainly include the following aspects:

    1. Eliminating the negative process in the exposure process

      The LDI technology eliminates the step of making the negative in the traditional exposure process, thereby saving the time and cost of loading and unloading the negative, and reducing the deviation caused by the negative growth and contraction.

      2. High resolution

      The image resolution of LDI technology is very high, which is suitable for some very fine line production, especially for multi-layer PCB, which greatly improves the yield of PCB production.

      3. High quality and precision

      LDI is contactless operation, reducing the chance of miscontact, the closed operating environment reduces the influence of temperature and humidity, the image quality is high and fine, eliminating many defects in the traditional process.

      4. Reduce errors and improve alignment

      LDI technology improves alignment by eliminating alignment problems that often exist in photographic plates, especially the anisotropic movement of photographic plates caused by changes in temperature and humidity. High-precision alignment is achieved by using a charge-coupled device (CCD) camera system and a reference target to line up printed images and panels.

      5. Shorten the production process and reduce costs

      Because there is no need to have a negative production process, LDI technology shortens the production process, reduces the call of personnel, and reduces the production cost. In addition, the LDI system can lay more devices in the same environment, enabling two-way scanning and further savings.

      6. Adapt to a variety of production needs

      LDI technology has a flexible manufacturing route, which can meet various production needs without affecting the output. Once the data is delivered to the engineering department, production can begin, reducing product delivery time.

      The image quality of LDI technology is clearer than that of traditional exposure technology, and it has obvious advantages in mid-to-high-end PCB manufacturing. With the transfer of global PCB production capacity to China and the high-end development of the electronics industry, the demand for LDI equipment continues to grow, and it is expected that the future will gradually replace traditional exposure equipment in the field of low-end PCB.

      What is the Process of Direct Imaging?

      Direct imaging with LDI involves several steps that ensure precise layer creation:

      • Design Preparation: The digital circuit design is prepped for imaging, with adjustments made to accommodate laser processing specifics.
      • Photoresist Coating: The PCB is coated with a light-sensitive photoresist material, which reacts chemically when exposed to the laser.
      • Laser Imaging: The laser projects the circuit pattern directly onto the photoresist. Adjustments can be made mid-process, allowing for precise alignment.
      • Developing: After exposure, the board is treated with a developer to reveal the circuit paths. Unexposed areas are removed, leaving only the intended design.
      • Etching or Plating: Depending on the PCB type, the board undergoes etching or plating to define the copper traces, completing the imaging process.

      Difference Between Positive and Negative Images in PCB

      In PCB photo exposure, the terms “positive” and “negative” refer to how the photoresist reacts to the laser exposure:

      • Positive Image: Here, the laser exposes areas intended to be removed. During development, the exposed regions dissolve, leaving behind the unexposed areas as the design.
      • Negative Image: In a negative image process, the laser exposes the regions meant to remain on the board. These exposed parts resist the developer, protecting the underlying material, while unexposed regions dissolve away.
      What is Laser Direct Imaging in PCB Manufacturing?

      The choice between positive and negative imaging depends on the photoresist type and the specific design requirements. Both methods offer high accuracy, but each has unique benefits based on the intended application.

      Why LDI Process Less Cost-effective than Phototool?

      While LDI offers many advantages, it often requires a higher initial investment than phototools:

      1. Equipment Costs: LDI machines are sophisticated and costly, requiring a significant investment in laser technology and imaging systems.

      2. Maintenance: High-precision lasers and optics demand regular maintenance and calibration to ensure consistent performance, which adds to operational costs.

      3. Speed on Larger Runs: For high-volume production, phototools may still be more cost-effective. Phototools offer rapid replication without the need for repeated laser exposure, lowering costs for large-scale production.

      These cost factors make LDI more suitable for specialized, lower-volume, or high-precision applications rather than large-batch productions.

      How is Layer Registration in LDI?

      Layer registration is crucial in PCB manufacturing, especially for multilayer boards where each layer must align precisely. LDI excels in this aspect:

      1. Automated Alignment: LDI systems come with advanced alignment software that adjusts each laser exposure to match the existing layer positions.

      2. Reduced Human Error: Since the process is largely automated, human handling is minimal, reducing the risk of alignment issues.

      3. Dynamic Adjustment: With real-time feedback systems, LDI machines adjust alignment during the process, maintaining tight registration tolerances.

      If you’re seeking high-quality PCB manufacturing, consider choosing a provider skilled in LDI processes like Best Technology. Our company combines expertise with cutting-edge technology to ensure your boards are produced to exact specifications, delivering the durability and performance you need in today’s advanced electronics.

      PCB Surface Treatments: A Comprehensive Guide

      29 10 月, 2024

      Printed Circuit Boards (PCBs) are the backbone of modern electronics. To ensure optimal performance and durability, PCBs undergo various surface treatments. These treatments protect the copper traces from corrosion, enhance solderability, and improve the overall reliability of the circuit board. In this article, we’ll explore the most common PCB surface treatments and their applications.

      1. HASL (Hot Air Solder Leveling)

        Principle

        HASL is a traditional surface treatment that involves immersing the PCB in a bath of molten solder. After the solder solidifies, hot air is used to level the surface and remove excess solder.

        Features

        •Material: Lead-tin alloy (for traditional HASL) or lead-free solder (for LF HASL).

        •Process: Immersion in molten solder followed by hot air leveling.

        Advantages

        •Excellent solderability.

        •Cost-effective for large volumes.

        •Good mechanical strength.

        Picture

        PCB Surface Treatments: A Comprehensive Guide

        2. OSP (Organic Solderability Preservatives)

        Principle

        OSP involves applying a thin layer of organic material (usually a rosin-based compound) to the copper surface, which protects it from oxidation.

        Features

        •Material: Organic preservatives.

        •Process: Application of organic film.

        Advantages

        •Environmentally friendly.

        •Good solderability.

        •Suitable for rework.

        Picture

        PCB Surface Treatments: A Comprehensive Guide

        3. ENIG (Electroless Nickel Immersion Gold)

        Principle

        ENIG involves depositing a layer of nickel followed by a thin layer of gold on the copper surface. This provides a robust barrier against corrosion and ensures good solderability.

        Features

        •Material: Nickel and gold.

        •Process: Electroless nickel deposition followed by immersion gold plating.

        Advantages

        •High reliability.

        •Excellent solderability.

        •Long shelf life.

        Picture

        PCB Surface Treatments: A Comprehensive Guide

        4. ENEPIG (Electroless Nickel Electroless Palladium Immersion Gold)

        Principle

        ENEPIG is similar to ENIG but adds a palladium layer between the nickel and gold. This improves the resistance to wear and tear.

        Features

        •Material: Nickel, palladium, and gold.

        •Process: Electroless nickel deposition, electroless palladium, and immersion gold plating.

        Advantages

        •Superior wear resistance.

        •Excellent solderability.

        •Long-term reliability.

        Applications

        •High-reliability military and aerospace applications.

        •High-frequency applications.

        •Wire bonding

        Picture

        PCB Surface Treatments: A Comprehensive Guide

        5. Gold Immersion (Direct Gold Plating)

        Principle

        Gold immersion directly deposits a layer of gold onto the copper surface without a nickel underlayer.

        Features

        •Material: Gold.

        •Process: Direct gold plating.

        Advantages

        •High conductivity.

        •Excellent solderability.

        • Silver Immersion

        Principle

        Silver immersion involves depositing a layer of silver onto the copper surface.

        Features

        •Material: Silver.

        •Process: Immersion silver plating.

        Advantages

        •High conductivity.

        •Low cost compared to gold.

        Picture

        PCB Surface Treatments: A Comprehensive Guide

        6. Hard Gold (Selective Gold Plating)

        Principle

        Hard gold is a thicker and harder layer of gold, typically applied selectively to contact areas.

        Features

        •Material: Gold.

        •Process: Selective gold plating.

        Advantages

        •High wear resistance.

        •Good electrical contact properties.

        Picture

        PCB Surface Treatments: A Comprehensive Guide

        7. Tin Immersion

        Principle

        Tin immersion deposits a layer of tin onto the copper surface.

        Features

        •Material: Tin.

        •Process: Immersion tin plating.

        Advantages

        •Good solderability.

        •Low cost.

        Applications

        •Cost-sensitive applications.

        •General-purpose electronics.

        Picture

        PCB Surface Treatments: A Comprehensive Guide

        Choosing the right surface treatment for your PCB depends on several factors, including the application environment, cost considerations, and performance requirements. Each treatment has its own set of advantages and limitations. Understanding these treatments will help you make informed decisions that enhance the performance and longevity of your electronic devices.

        I hope this guide helps you understand the different surface treatments used in PCB manufacturing and their applications. If you have any questions or need further clarification, feel free to reach out!

        What is ICT Full Form in PCB?

        26 10 月, 2024

        ICT Test Full Form

        The full form of ICT is In-Circuit Testing. It is a method that always used to test assembled circuit board during manufacturing.

        What is ICT in PCB?

        In-circuit testing (ICT) is a method used to test assembled circuit boards during production. It ensures that every component on the PCB functions as expected. By applying electrical signals to the board, it checks for faults like open circuits, shorts, and wrong component values.

        In PCB assembly, ICT is used for final testing after surface-mount components and through-hole components have been soldered onto the board. This test is highly effective in identifying assembly defects that might compromise the functionality of the final product.

        What is ICT Full Form in PCB?

        ICT vs. FCT

        Although ICT and FCT look similar, their purposes and focus are different.

        In-Circuit Testing (ICT) is like a thorough quality check for individual components. It tests each resistor, capacitor, inductor, and IC on the board to make sure they’re installed and working as expected. ICT does this without focusing on the PCB’s complete function as a whole; instead, it looks for manufacturing faults or placement errors on each part of the circuit. This is perfect for catching problems before the PCB reaches final assembly.

        Functional Circuit Testing (FCT), on the other hand, looks at the bigger picture. FCT checks if the assembled board works as intended in a simulated working environment. It mimics the real-world conditions the PCB will face once in use, testing the board as a whole rather than individual components. FCT aims to ensure that all parts are correctly interacting and that the board behaves as it should under operating conditions.

        What is ICT Full Form in PCB?

        Together, ICT and FCT form a powerful duo: ICT focuses on each component’s accuracy, while FCT ensures that all the elements work smoothly as a cohesive unit. Using both tests provides a comprehensive check, enhancing the PCB’s overall quality and reliability before it reaches the end-user.

        What Items Does ICT Test for on a PCBA?

        When ICT tests a PCBA, it’s really looking for any faults or failures in the components and connections that could cause problems later on. Here’s what ICT commonly checks:

        • Resistors – It verifies that each resistor has the right resistance value and is correctly placed. If a resistor value is wrong, it can disrupt the whole circuit.
        • Capacitors – ICT checks capacitance levels and polarity (in specific cases) to make sure each capacitor is installed properly. Incorrect capacitors can lead to unstable performance.
        • Inductors – The test examines if inductors have the correct inductance values. Faulty inductors can cause power issues or signal problems.
        • Integrated Circuits (ICs) – ICT verifies that ICs are in the right orientation and connected properly to avoid shorts or opens, both of which can make the board malfunction.
        • Transistors – By checking transistor functionality, ICT ensures they won’t cause signal or power issues within the PCB.
        • Diodes – ICT makes sure diodes have correct polarity and work properly. Misplaced or faulty diodes can impact the flow of current, leading to circuit failure.
        • Solder Joints – ICT evaluates each solder joint, checking for breaks or poor connections. Bad solder joints lead to unstable electrical contact, which could cause intermittent issues or complete failure.

        What is an ICT Machine?

        An ICT machine is a specialized piece of equipment designed to perform in-circuit tests on PCBs. You can see it from below picture. The ICT machine uses a test fixture, also called a “bed of nails,” containing numerous tiny probes or pins. Each probe aligns with a specific point on the PCB, making contact with various circuit points to evaluate the electrical connections.

        Once a PCB is placed in the test fixture, the machine applies signals through the probes to test individual components. It checks electrical properties such as resistance, capacitance, and voltage at each node. If a component is misplaced, missing, or faulty, the machine flags it immediately.

        What is ICT Full Form in PCB?

        With its speed and precision, an ICT machine is an invaluable tool in high-volume production lines. While setting up an ICT machine requires creating a test fixture for each PCB, they save much time and human during the manufacturing process, make sure a fast delivery.

        What Are the 7 Types of PCB Testing Methods?

        In addition to ICT testing, there are other 6 types of PCB testing methods that widely used. Let’s talk about them one by one.

        1. Flying Probe Testing

          A testing method mainly used for prototypes or small/low volume orders. In Flying Probe Testing, multiple movable probes make contact with test points on the board. Unlike ICT, it doesn’t require a fixture, making it highly flexible and cost-effective for small production runs. However, compared with ICT testing, it’s relatively slower than ICT because it tests points sequentially.

          2. Functional Circuit Testing (FCT)

          FCT is a method that check whether PCBA works correctly. It is typically come after ICT, and in almost factory, it is the last process to confirm that every component works together correctly.

          3. Burn-In Testing

          Burn-in Testing (also called aging test) pushes the board to its limits by applying high temperatures, loads, or voltages for extended periods. It can spot failures in components that might not withstand the stress of real-world conditions. Burn-in testing is often used for products that need high reliability, such as aerospace and medical devices.

          4. X-Ray Inspection

          For multilayer or densely packed PCBs, X-ray inspection is must to do. It helps visualize hidden solder joints and component placements that inspectors can’t found by naked eyes. X-ray inspection is invaluable for boards with fine-pitch components such as BGAs, QFNs, or those where hidden joints can’t be inspected visually.

          5. Automated Optical Inspection (AOI)

          AOI uses cameras to visually inspect the board for common issues like misalignment, missing components, or faulty solder joints. This is a quick and effective way to catch visible defects. AOI is widely used in automated production lines, as it quickly flags any boards that require closer examination. To get highest quality and no-defect products, Best Technology equipped with online dual track AOI to inspect PCBA.

          6. Boundary Scan Testing

          Boundary Scan Testing is particularly useful for complex boards where physical probing is challenging. It involves using ICs that support scan testing, so that engineers to check connectivity between ICs and other critical points. Boundary scan is common in high-density boards like those found in telecommunications.

          Each method brings a unique advantage to PCB testing. In-Circuit Testing (ICT) is highly effective for large-scale quality control, while Flying Probe Testing is better suited for prototypes and smaller batches. Together, these tests form a complete strategy for delivering reliable, high-quality PCBs across various production needs.

          How does ICT Testing?

          ICT works by using a bed-of-nails (BON) tester or test probes to connect to specific test points on a PCB. Electrical signals are then sent through the board, and the responses are analyzed. Here’s how it works in simple steps:

          • Connection: The PCB is placed on the ICT machine, where test pins contact the board at designated points.
          • Signal Application: The ICT machine applies electrical signals to test the components individually or in groups.
          • Data Collection: The responses from each component are recorded to determine if it matches the expected output.
          • Fault Identification: Any deviations from expected responses are flagged, identifying potential defects like soldering errors, component failures, or incorrect placements.

          FAQs about ICT

          Q: What is ICT?

          A: ICT (In-Circuit Test System), commonly known as online tester In Chinese, is mainly used for the test of assembled Circuit boards (PCBA).

          Q: Which components can ICT basic functions measure?

          A: On, short circuit, resistance, capacitance, inductance, diode, IC protection diode test, etc.

          Q: Why use ICT?

          A: According to the statistical data of the circuit board assembly industry, assembly defects are mainly reflected in the welding open circuit, short circuit, offset, missing parts and other aspects, accounting for more than 90%, so the principle of online testing technology application is to quickly detect faulty components or assembly defects, and can accurately locate defects and defect classification.

          Q: Can ICT be regarded as a universal meter?

          A: ICT can be regarded as an automated high-level multipurpose meter, and because it has the function of circuit isolation, it can accurately measure the actual value of each component in the circuit.

          Q: What is the relationship between ICT and AOI?

          A: ICT is mainly carried out by electrical measurement methods, while AOI is carried out by optical image processing technology. Both have their own strengths and complement each other. In the process arrangement, AOI is generally the first, then ICT.