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10 Common Components on a PCBA for Beginners
Wednesday, September 4th, 2024

Even though we live in a world full of electronic gadgets, electronic devices are still shrouded in mystery. The working principle of electronic projects may seem very abstract, as the interior of these gadgets does not seem to have any visible mechanical parts. There are no moving parts such as gears or shafts on the printed circuit board, nor any significant visual changes.

The flow of electricity is invisible and can only be perceived by the effect it produces. Therefore, for those who want to dabble in the field of electronics making, making electronics as a hobby can seem like an extremely challenging task. It seems hard to imagine building something without fully understanding the principles behind it.

What does PCBA mean?

PCBA is the abbreviation of Printed Circuit Board Assembly, which refers to the process of welding, inserting, etc. of electronic components to the circuit board, and welding, inserting, etc. PCBA is an indispensable and important link in the manufacture of electronic products, which directly affects the performance stability and service life of electronic products.

The manufacturing process of PCBA mainly includes components mounting, welding, post-welding processing and functional testing. The first is the component mounting, which is a process of welding the patch components, plug-in components, etc., to the PCB. Then there is welding, through traditional wave soldering or modern lead-free welding and other methods, the components are firmly fixed on the PCB. After that, the welding process is mainly to remove the welding slag on the PCBA surface, clean the PCBA surface, and check the solder joints and components of PCBA. Finally, the functional test is carried out, which is the last step in the PCBA process, and the PCBA is fully functional tested by various test equipment to ensure the stability and reliability of PCBA.

Applications of PCBA

PCBA products are widely used in various electronic products, such as household appliances, communication equipment, automotive electronics, industrial control equipment, etc.  You can see it everywhere.

Different electronic products have different requirements for PCBA. Some require PCBA to be small and exquisite, some require PCBA to be high temperature and high pressure resistant, and some require PCBA to be waterproof and dustproof. With the rapid development of 5G, artificial intelligence, Internet of Things and other fields, PCBA will be more widely used, and PCBA’s performance and reliability requirements will also be higher.

Common components on a PCBA and their symbols

1. Resistor

    Resistors are one of the most commonly used electronic components in PCBA, used to limit the current in the circuit. According to different materials, structures, and resistance values, resistors can be divided into fixed resistors, variable resistors, and special resistors. Resistors are widely used in various circuits, such as power circuits, amplification circuits, signal processing circuits, etc., to achieve current regulation and control.

    2. Capacitor

    A capacitor is a component that stores charge and electrical energy, with the characteristic of blocking direct current and passing alternating current. In PCBA, capacitors are commonly used in circuits such as filtering, coupling, tuning, and bypassing to improve circuit performance and stability. According to their different structures and applications, capacitors can be divided into fixed capacitors, variable capacitors, and fine tuned capacitors.

    3. Inductor

    Inductor, also known as induction coil, has the function of storing magnetic energy. In circuits, inductors can prevent changes in current and play a role in filtering and stabilizing the current. Inductance has a wide range of applications in power filtering, signal processing, and other fields.

    4. Diode

    A diode is an electronic component with unidirectional conductivity, widely used in circuits such as rectification, detection, and voltage regulation. In PCBA, diodes can achieve functions such as voltage regulation, signal amplification, and switch control in the circuit. Common diodes include silicon diodes and germanium diodes, whose performance parameters such as forward voltage drop and reverse breakdown voltage determine their application scenarios.

    5. Transistor

    Transistors are electronic components with functions such as amplification and switching, and are the core components that make up various circuits. In PCBA, transistors are commonly used in amplification circuits, oscillation circuits, switch circuits, etc. to achieve signal amplification, frequency conversion, and circuit control. There are many types of transistors, including bipolar transistors, field-effect transistors, etc., each with its own characteristics, widely used in various electronic devices.

    6. IC Integrated circuit

    Integrated circuit is an electronic component that integrates multiple electronic components on a single chip, with advantages such as small size, low power consumption, and stable performance. In PCBA, integrated circuits are key components for implementing various complex functions, such as digital signal processing, analog signal processing, communication interfaces, etc. Common integrated circuits include operational amplifiers, logic gate circuits, microprocessors, etc., which are widely used in various intelligent devices and systems.

    7. Sensor

    Sensors can sense physical quantities or states in the environment and convert them into electrical signals for output. In PCBA, sensors are commonly used to detect parameters such as temperature, humidity, light, pressure, etc., providing data support for intelligent control of electronic devices. There are various types of sensors with different performances, and choosing the appropriate sensor is crucial for improving the performance and user experience of electronic devices.

    8. Controllable silicon rectifier (SCR)

    Also known as thyristors, silicon controlled rectifiers (SCR) are similar to transistors and diodes – their working principle is essentially the coordinated operation of two transistors. Although SCR also has three pins, they are composed of four layers of silicon material instead of three layers, and are only used as switches, not amplifiers. Unlike single transistors that require continuous current to remain on, SCR only requires one pulse to activate the switch. They are very suitable for converting large amounts of electricity.

    9. Crystal oscillator

    Crystal oscillators provide clock signals in many circuits that require precise and stable timing. By physically oscillating piezoelectric materials (such as crystals), they generate periodic electronic signals, hence their name. Each crystal oscillator is designed to vibrate at a specific frequency, which is more stable, economical, and smaller in size than other timing methods. That’s why they are commonly used for precise timing in microcontrollers, or more commonly as clock components in quartz watches.

    10. Switches and relays

    A basic and easily overlooked component, a switch is simply a power button that controls the current in a circuit by switching between open or closed circuits. They vary greatly in appearance, from sliders, rotations, buttons, levers, toggles, key switches, and more. Similarly, a relay is an electromagnetic switch that operates through a solenoid, acting like a temporary magnet when a current flows through it. They act as switches and amplify small currents into larger ones.

    Now that you’re familiar with some basic electronic components, why not dive into creating your own electronics project? Instead of starting with a complex project featuring advanced functions, begin with a few simple ones. As with any hobby, you’ll encounter challenges along the way, but these hurdles are not insurmountable. With accessible and affordable beginner electronics tools like Arduino and CAD tools, the maker community welcomes new PCB designs and projects every day.

    In addition to PCB manufacturing, Best Technology offers a full turnkey service, including parts procurement and assembly. Whether you’re working on prototypes or scaling up to mass production, Best Team provides a one-stop solution for seamless and hassle-free PCB assembly.

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    What is an amplifier board? Its functions and types
    Wednesday, September 4th, 2024

    A power amplifier board is a circuit board specially designed to enhance audio signals. It is the core component of the audio system, which can enhance weak signals to a level that can effectively power speakers or other output devices. In modern audio equipment, the existence of power amplifier boards is indispensable.

    What is an amplifier board?

    The amplifier board is an important part of the amplifier, which is mainly responsible for the power amplification function, that is, converting low-level signals into high-level signals to drive the speakers to produce loud and clear sounds.

    The amplifier board is usually composed of a power amplifier device and a speaker protection device, and its effect directly affects the performance of the entire amplifier.

    The difference between the amplifier board and the amplifier is that the amplifier usually contains a preamplifier, a post-amplifier and an output stage, etc., and is a complete unit suitable for larger occasions such as KTV rooms and theaters.

    The amplifier board mainly contains a post-amplifier and an output stage, lacks a preamplifier, is smaller in size, has lower power, and is more suitable for personal use, such as home theaters. In addition, the price of the amplifier is higher, while the price of the amplifier board is relatively cheap.

    What does an amplifier board do?

    The main function of the amplifier board is to amplify the sound signal and increase the power of the audio signal, so that the sound is clearer and louder. ‌

    What is an amplifier board? Its functions and types

    The amplifier board plays a vital role in audio equipment. It is mainly responsible for converting the power of audio signals so that higher sound output can be produced in a relatively small space.

    In the audio circuit, the role of the amplifier board is particularly obvious. It works together with components such as preamplifiers, control amplifiers, power amplifiers and speakers to amplify the input audio signals through the amplifier board and convert them into clear and high-fidelity sounds, achieving high-quality performance of the audio.

    In addition, the use of amplifier boards can make audio equipment more powerful, not only providing more beautiful sound effects, but also better protecting the stability of the audio equipment itself. Therefore, amplifier boards are widely used as important components in the production of audio equipment.

    In summary, the amplifier board amplifies the power of the audio signal, allowing the audio equipment to output higher quality and louder sound, thereby enhancing the listening experience. Whether it is a professional audio or a home theater system, the amplifier board is an indispensable component‌.

    How does an amplifier board work?

    The working principle of the amplifier board is mainly based on the principles of electronic engineering and physics. Through the combination of amplifiers and power supplies, the input signal is amplified and output to the speaker. ‌

    The core component of the power amplifier board is the amplifier, which has many types, such as voltage amplifier, current amplifier, damping amplifier, etc. Each type of amplifier has different amplification effects and signal transmission methods.

    When the input signal is transmitted to the power amplifier board through the amplifier, the energy supplied by the power supply makes the level of the output signal greater than the input signal level, thereby playing the role of amplifying the signal. In this process, the power supply provides energy to the amplifier in the form of direct current to control the waveform and frequency of the output signal.

    From a technical point of view, the power amplifier board is like a current modulator, which converts alternating current into direct current, and then is controlled by the sound signal played by the sound source to transmit currents of different sizes to the speakers at different frequencies, so that the speakers emit sounds of corresponding sizes and frequencies.

    The working modes of the power amplifier include Class A power amplifier, Class B power amplifier and Class AB power amplifier, each type has its own characteristics and applicable scenarios.

    In short, the working principle of the power amplifier board involves the interaction of multiple physical and electronic engineering principles. Through carefully designed circuits and components, the input audio signal is amplified and output to the speaker, thereby producing the sound we hear‌.

    What are the different types of amplifier boards?

    There are four main types of amplifier boards: Class A, Class B, Class AB, and Class D. ‌

    1. Class A amplifier:

    Class A amplifiers are amplifiers in which no power output element of the amplifier will experience current cutoff (i.e. stop output) during the entire cycle of the signal. This type of amplifier generates high heat when working and has very low efficiency, but the inherent advantage is that there is no crossover distortion.

    Class A amplifiers have the best linearity and almost no distortion, so they can provide high-quality audio amplification with pure and realistic sound quality. However, due to low efficiency, Class A amplifiers have high body temperatures and require good heat dissipation design.

    2. Class B amplifiers:

    Class B amplifiers work completely differently from Class A amplifiers. In Class B amplifiers, the positive and negative channels of the transistors are usually in a closed state unless there is a signal input. This means that when there is no signal input, the output transistors do not conduct electricity and consume no power.

    When there is a signal, each pair of output tubes amplifies half of the waveform, and takes turns to complete a full-wave amplification, thus generating crossover distortion. The advantage of Class B amplifiers is high efficiency, but the sound begins to distort when the signal is very low, and the sound becomes rough.

    3. Class AB amplifiers:

    Class AB amplifiers combine the characteristics of Class A and Class B. They use Class A when the signal is small, and gradually transition to Class B working mode as the signal increases. This method aims to balance the high fidelity of Class A with the high efficiency of Class B, reduce crossover distortion, and improve efficiency.

    4. Class D amplifiers:

    Class D amplifiers are high-efficiency amplifiers that achieve high-efficiency conversion through high-frequency pulse width modulation technology. The design of Class D amplifiers makes it consume almost no power when there is no signal input, and when there is a signal input, it amplifies the signal through high-frequency switching, thereby achieving high-efficiency energy conversion.

    The advantage of Class D amplifiers is extremely high efficiency, but the design is relatively complex and requires precise control circuits to ensure sound quality.

    In summary, different types of amplifiers have their own characteristics in terms of efficiency, sound quality, application scenarios, etc. Choosing the right type of amplifier depends on specific application requirements and personal preferences.

    What are the disadvantages of amplifier board?

    The disadvantages of amplifier boards mainly include high power consumption, high cost, high distortion, severe digital flavor, and cold sound. ‌

    1. High power consumption and high cost:

    Due to its working mode, Class A amplifiers have the problems of high power consumption and high cost. This type of amplifier performs well in bass performance and distortion control, but the corresponding energy consumption and cost investment are also high.

    2. High distortion:

    Digital amplifiers may generate noise and nonlinear distortion during digital conversion, which will affect the sound quality. In addition, digital amplifiers have high requirements for power supply noise processing, and the cost of the whole machine is relatively high, especially compared with traditional analog amplifiers.

    3. Severe digital flavor and cold sound:

    Digital amplifiers may be considered to have a serious digital flavor in sound quality, and the sound is cold and not warm enough, which may not meet the hearing preferences of all users.

    In summary, different types of power amplifier boards have their own advantages and disadvantages, and the choice needs to be weighed according to personal needs and preferences.

    What is the difference between a power amplifier and an amplifier board?

    A power amplifier is an electronic device designed to amplify the power of an input signal to drive a load (such as a speaker, antenna, etc.). It is a key component in audio systems, radio communication equipment, etc.

    What is an amplifier board? Its functions and types

    A power amplifier board generally refers to a circuit board or module used to assemble or apply a power amplifier. It contains all the components and circuit designs required for a power amplifier. An amplifier board can be a stand-alone circuit board for integration into a larger system or for DIY projects.

    Conclusion:

    Amplifier boards are an indispensable component in modern audio systems, providing the necessary amplification to ensure clear and powerful sound. Whether you are looking for high efficiency, excellent sound quality, or both, there is an amplifier board that suits your needs.

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    What is BGA? What is its use?
    Friday, August 30th, 2024

    Ball grid array (BGA) is a surface mount package for integrated circuits. Its ability to accommodate a large number of pins while maintaining a small footprint makes it ideal for modern electronic devices with limited space. BGA packages are used in a variety of applications, from consumer electronics such as smartphones and laptops to industrial equipment and automotive systems.

    What is BGA?

    Ball grid array (BGA) is a common surface mount package that is derived from pin grid array (PGA) technology. It uses a grid of solder balls or leads to conduct electrical signals from the integrated circuit board. Instead of using pins like PGA, BGA uses solder balls placed on a printed circuit board (PCB). By using conductive printed wires, PCBs support and connect electronic components.

    What is BGA? What is its use?

    Unlike PGA, which has hundreds of pins and is difficult to solder, BGA solder balls can be evenly distributed without accidentally connecting them together. Solder balls are first placed in a grid pattern on the bottom of the package and then heated. By using surface tension when melting the solder balls, the package can be aligned with the circuit board. The solder balls cool and solidify, with accurate and consistent distances between each other.

    What does a BGA do?

    The main role of BGA (Ball Grid Array) packaging technology includes providing high-density, high-performance packaging solutions for microprocessors, ASICs, DSPs, PDAs, PLDs and other devices. This technology achieves surface mounting by making array solder balls on the bottom of the package substrate as the I/O end of the circuit to interconnect with the printed circuit board (PCB).

    What is BGA? What is its use?

    BGA packaging technology is small, light, and high-performance. It can provide more pins than other packaging technologies such as dual in-line package (DIP) or quad flat package (QFP). The entire bottom surface of the device can be used as pins instead of only the periphery.

    This allows BGA packages to have shorter average wire lengths than periphery-limited package types, thereby providing better high-speed performance.

    The advantages of BGA packaging are not only its high density and high performance, but also its less stringent requirements for welding accuracy. Even during the soldering reflow process, even if the solder ball is offset from the pad, the device position can be automatically corrected due to the surface tension of the solder.

    What are the disadvantages of BGA?

    The disadvantages of BGA packaging technology mainly include difficulty in detection, high difficulty in repair, relatively high production cost, stricter requirements on the reliability of solder joints, and sensitivity to temperature and humidity. ‌

    1. Difficulty in detection: Since the solder ball is located at the bottom of the chip, the traditional optical inspection method cannot effectively detect the welding quality, and X-ray detection and other equipment must be used, which increases the cost and time of detection. ‌

    2. High difficulty in repair: If there is a welding problem, the BGA packaged device needs to be disassembled and reassembled. This process has high technical requirements and certain risks. ‌

    3. Relatively high production cost: Compared with QFP packaging, BGA packaging has higher material, production and inspection costs. ‌

    4. More stringent requirements on the reliability of solder joints: Due to its small size, the BGA packaging method has very high requirements on solder joints. If there are problems such as empty solder joints and cold solder joints in the solder joints, the BGA package will fail.

    5. Sensitive to temperature and humidity: BGA packaged components are very sensitive to temperature and humidity and need to be stored under constant temperature and dry conditions.

    These shortcomings have limited the widespread application of BGA packaging technology to a certain extent, especially in application scenarios with high requirements for cost, reliability and environmental adaptability.

    How is BGA made?

    The production process of BGA (ball grid array package) mainly includes several key steps, which ensure the high quality and high reliability of BGA package. ‌

    1. Wire bonding PBGA packaging process flow:

    Substrate preparation: extremely thin copper foil is laminated on both sides of the BT resin/glass core board, and then drilling and through-hole metallization are performed.

    ‌Graphic production: Use conventional PCB processing technology to make graphics on both sides of the substrate.

    ‌Solder mask production: Add solder mask and make graphics to expose electrodes and welding areas to improve production efficiency. A substrate usually contains multiple PBGA substrates.

    2. ‌BGA area via plugging‌:

    The vias in the BGA pad area generally need to be plugged to prevent foreign matter in the hole or to protect the service life of the via, and to prevent the via from tinning during the reflow soldering of the SMT patch, causing a short circuit on the other side.

    3. ‌Via in the plate, HDI design‌:

    For BGA chips with small pin spacing, when the pin pad cannot be connected due to the process, it is recommended to directly design the via in the plate, and use the HDI blind buried hole wiring method to design the PCB, punch the via in the plate on the BGA pad, punch the buried hole in the inner layer, and conduct the wiring in the inner layer.

    4. ‌BGA welding process‌:

    ‌Printing solder paste‌: Apply an appropriate amount of solder paste evenly on the PCB pad to ensure that the patch components and the corresponding pads on the PCB achieve good electrical connection and sufficient mechanical strength during reflow soldering.

    ‌Device placement‌: Use a placement machine to accurately mount the chip components to the corresponding position on the PCB surface printed with solder paste or patch glue.

    5. Special size design and automated production:

    BGA features include high pinhole density, easy automated production, high reliability, and the ability to design special sizes to achieve a more compact chip layout.

    What is the difference between PCB and BGA?

    The main differences between PCB and BGA are their structure, function, and application scenarios. ‌

    1. Structure:

    PCB (printed circuit board) is a basic electronic component that provides an electrical connection path between components. BGA (ball grid array package) is an advanced packaging method that connects components to PCB through a spherical pad array, with the advantages of high density and high reliability.

    The pins of BGA are spherical and are generally directly soldered on the PCB board. Desoldering requires a special BGA rework station, and individuals cannot desolder; while the pins of PGA (pin grid array package) are pin-shaped. When installing, the PGA can be inserted into a special PGA socket for easy disassembly.

    2. Functions and application scenarios:

    BGA packaging effectively uses PCB space, which helps save enough space for customization in PCB and improve its efficacy. The size of BGA package is very small, so these PCBs have less heat dissipation and are easy to achieve the dissipation process.

    There are no bendable or fragile pins in BGA package, so the durability of these PCBs is increased, and good electrical performance is also ensured. The pads of BGA package are large enough to make it easy to solder and easy to operate, so easy soldering and handling make it very fast to manufacture.

    In summary, BGA, as an advanced packaging technology, has been widely used in high-performance electronic products through its unique ball grid array structure and high density and high reliability characteristics. Traditional PCBs provide basic electrical connection paths and are the basic components of electronic devices.

    How many types of BGA are there?

    There are many types of BGA, mainly including:

    1. PBGA (plastic package BGA): This is the most commonly used BGA packaging form, made of plastic materials and plastic processes.

    What is BGA? What is its use?

    2. CBGA (ceramic BGA): This packaging type uses a multi-layer substrate with precious metal interconnect circuits.

    3. CCGA (ceramic solder column array)

    4. TBGA (BGA with tape)

    5. MBGA (metal BGA)

    6. FCBGA (flip chip BGA)

    7. EBGA (BGA with heat sink)

    In addition, BGA can be divided into staggered type, full array type, and peripheral type according to the arrangement of solder balls.

    Conclusion:

    Ball grid array (BGA) packaging is a key technology in modern electronic products. It makes it possible to develop more powerful and compact devices. BGA has become the first choice for applications that require high performance, reliability and miniaturization.

    BGA packaging is famous for its advanced packaging technology. BEST Technology is recognized as the most trusted one-stop electronic circuit solution provider in the world, and BGA production is one of its most important projects. We specialize in the production and assembly of PCBs containing BGA packaging.

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    How to use solder flux?
    Tuesday, August 27th, 2024

    In the manufacturing process of printed circuit boards, it is very necessary to apply a proper amount of flux. The soldering pads, copper bars of components and the surface of solder paste are the places where flux should be applied, which can improve the firmness of the soldering points and the quality of printed circuit boards.

    What is flux?

    Flux: A chemical substance that can help and promote the soldering process in the soldering process, and at the same time has a protective effect and prevents oxidation reactions. Flux can be divided into solid, liquid and gas.

    How to use solder flux?

    There are mainly several aspects such as “assisting heat conduction”, “removing oxides”, “reducing the surface tension of the material to be soldered”, “removing oil stains on the surface of the material to be soldered, increasing the soldering area”, and “preventing re-oxidation”. Among these aspects, the two most critical functions are: “removing oxides” and “reducing the surface tension of the material to be soldered”.

    Do you apply flux before or after soldering?

    Use flux before soldering printed circuit boards. ‌

    How to use solder flux?

    During the soldering process of printed circuit boards, the main purpose of using flux is to improve soldering performance and help the metal avoid the formation of an oxide film that hinders solder wetting when heated, thereby promoting the formation of solder-metal alloys and avoiding the occurrence of cold soldering and false soldering.

    Flux can be applied to the printed circuit board before soldering, or it can be used as part of the solder during the soldering process, such as solder paste or solder oil. When tinning the pins of components, rosin should be used as the flux, and if the printed circuit board is already coated with rosin solution, then no additional flux is required during soldering.

    After using flux, make sure to wipe off the residual flux at the soldering site after soldering to avoid potential damage to electronic components and circuit boards.

    In addition, the preparation work before soldering includes thoroughly cleaning the copper foil surface and then applying rosin water to protect the copper foil and help soldering. This step is performed before soldering to ensure the smooth progress of the soldering process. Therefore, the correct approach is to use flux before soldering printed circuit boards to ensure the quality and reliability of soldering.

    How much flux to use when soldering?

    When soldering printed circuit boards, the amount of flux used needs to be determined according to the specific soldering method and the type of flux. For wave soldering flux, when using brushing and foaming methods, the specific gravity of the flux should be controlled between 0.82-0.84 (specific gravity of liquid rosin flux stock solution).

    During the soldering process, the specific gravity of the flux needs to be measured regularly. If the specific gravity is found to increase, it should be adjusted to the normal range with diluent in time, but the diluent should not be added too much to avoid affecting the soldering quality.

    For the quantitative spraying method, the key is that the nozzle can control the spray volume. The nozzle should be cleaned frequently to ensure that the spray hole is not blocked. The spray pressure should be controlled at 0.2-0.3Mpa, the flux pressure should be controlled at 0.4±0.05Mpa, and the spray flow rate should be controlled at 20-35ml/min.

    In addition, different types of flux formulas are also different. For example, rosin liquid can be made by mixing rosin blocks and alcohol in a ratio of 1:3. For the flux of printed circuit boards, you can directly use rosin water, and apply the prepared rosin water directly on the surface of the printed circuit board or the solder joints.

    When using flux, you should also pay attention to the following points:

    Put the bottle cap on immediately after use to prevent the flux from being in contact with air for a long time and causing oxidation reaction or absorbing water vapor in the air to cause the concentration to decrease.

    Regularly replace the flux that has been stored for too long, because long-term storage will cause the flux composition to change and the activation performance to deteriorate, affecting the welding quality.

    Clean it after welding, because the insulation performance of the flux will drop sharply at high temperature, and the residue may affect the heating components, and in severe cases may cause short circuits.

    In summary, the amount of flux used in printed circuit board welding needs to be determined according to the specific welding method and flux type, and pay attention to the use and storage conditions of the flux to ensure welding quality and safety.

    What happens if you use too much flux when soldering?

    First, the main functions of flux include assisting heat conduction, removing oxides, reducing the surface tension of the material being soldered, removing oil stains on the surface of the material being soldered, increasing the soldering area, and preventing reoxidation.

    However, excessive use of flux can lead to corrosion and electromigration. This is because improper use of flux, such as excessive use, can create more favorable conditions for potential chemical corrosion reactions.

    In addition, if the flux used is not well controlled, resulting in excessive use of flux, more flux residue will be left, which creates more favorable conditions for potential chemical corrosion reactions.

    Therefore, it is very important to control the amount of flux used to avoid negative effects on soldering quality and reliability.

    What happens if I don’t use flux?

    If flux is not used on printed circuit boards, it may lead to reduced soldering quality, increased soldering difficulty, and affect the performance and reliability of the circuit.

    1. Increased soldering difficulty: Without flux, the solder may be difficult to flow to the soldering point, resulting in loose soldering, prone to cold soldering or poor soldering.

    2. Reduce welding quality: Without the help of flux, the soldering point may not be smooth enough, with burrs or unevenness, which may affect the normal operation of the circuit.

    3. Affect circuit performance and reliability: Flux can reduce the resistance of the soldering point and improve the conductivity of the circuit. Without flux, the resistance of the soldering point may increase, affecting the performance and stability of the circuit.

    In addition, the flux can also prevent oxidation to a certain extent, protect the soldering point from the influence of the external environment, thereby improving the life of the circuit. Therefore, in the soldering process of printed circuit boards, it is very important to use the soldering flux correctly.

    What is an alternative to soldering flux?

    Alternatives to printed circuit board soldering flux include no-clean soldering flux, special solder resist for printed circuit boards, water-based cleaning agents and dry ice cleaning technology. ‌

    1. No-clean soldering flux is a new type of soldering flux that does not contain halide activators. It does not need to be cleaned after use, which can save investment in cleaning equipment and cleaning solvents, while reducing the emission of waste gas and wastewater, and the pollution to the environment is also reduced accordingly.

    2. The main function of the ‌PCB solder mask‌ is to prevent “wiring” and short circuits during wave soldering and protect the PCB permanently. In addition, it can save solder, reduce the weight of the PCB, and reduce costs.

    3. As a new type of cleaning medium, the ‌water-based cleaning agent‌ achieves cleaning through the wetting, dissolution, emulsification, saponification, chelation and other effects of the surfactants, emulsifiers, penetrants, etc.

    How to use solder flux?

    4. The ‌dry ice cleaning technology‌ uses extremely low-temperature dry ice particles to spray onto the treated object under the action of compressed air, so that the dirt is rapidly frozen to brittleness and burst, and then vaporized to take away the dirt.

    These substitutes have their own characteristics and are suitable for different application scenarios and technical requirements. When choosing, specific process requirements and cost-effectiveness must be considered.

    What does rosin do when soldering?

    In the process of printed circuit board soldering, rosin plays a vital role. It is mainly used as a flux to help the soldering process be smoother and more efficient. The role of rosin is reflected in the following aspects:

    ‌Removing oxide film‌: Rosin can remove the oxide film formed on the copper surface due to contact with air. These oxide films will prevent the tin from wetting the copper wire, thus affecting the quality of welding.

    ‌Preventing re-oxidation‌: Rosin can not only remove the oxide film, but also prevent the soldering surface from re-oxidizing during the welding process, which helps to maintain the stability and reliability of the welding point.

    ‌Isolating air‌: Under high temperature conditions of welding, rosin can isolate the air and prevent oxidation of the metal surface.

    In summary, rosin plays an important role in the soldering process of printed circuit boards. Through its fluxing effect, it improves the quality and reliability of soldering and is one of the indispensable materials in electronic manufacturing‌.

    Conclusion:

    Flux is a key part of the soldering process. Without it, your solder will not flow smoothly through the joint and the solder will not adhere properly to the various components on the circuit board. High-quality flux is necessary to produce good solder joints.

    BEST Technology is a professional PCB circuit board manufacturer with many years of experience in PCB circuit board welding. The circuit boards it produces are of extremely high quality. We have the most extensive experience to deal with all aspects of PCB welding issues.

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    What is a PCB assembly?
    Thursday, August 22nd, 2024

    PCB assembly is the process of combining a circuit board with other electronic components (such as connectors, housings, heat sinks, etc.) to embed into a final product. This process is a key step in the production of electronic equipment. Its main function is to provide a platform for electronic components to work together in a coordinated manner so that the equipment can perform its intended tasks.

    What is the standard for PCB assembly?

    The standards for PCB assembly mainly include PCB panel specifications, ISO standards, IPC standards, JEDEC standards, and ROHS standards. ‌

    What is a PCB assembly?

    ‌PCB panel specifications‌ involve the width, shape, frame design, center distance between small boards, setting of positioning holes, arrangement of reference symbols, and positioning of large components of the panel. The panel frame should adopt a closed-loop design to ensure that the panel is fixed on the fixture without deformation.

    ‌ISO standards‌ emphasize key factors such as fit tolerance, surface roughness, contact area, and tightening force in PCB tight-fit installation to ensure the accuracy and stability of installation‌.

    ‌IPC standards‌ include IPC-7711 and IPC-A-600E, the former provides basic recommendations and guidelines for the design and manufacture of printed boards, and the latter provides acceptable conditions and practice guidelines for printed boards.

    ‌JEDEC standards‌ provide specifications for circuit board materials, dimensions, interfaces, etc., including material selection, dimension design, interface specifications, test methods and quality assurance.

    ‌ROHS standard‌ is a directive on the restriction of the use of hazardous substances, aimed at reducing the impact on the environment and human health. It stipulates the use restrictions of hazardous substances such as lead, mercury, cadmium, hexavalent chromium, polybrominated biphenyls and polybrominated diphenyl ethers.

    Compliance with these standards ensures the quality, safety and environmental friendliness of PCB products, and also provides clear guidance and specifications for the design, manufacture and assembly of PCBs.

    Why is PCB assembly so expensive?

    The high cost of PCB assembly is mainly due to the combined influence of multiple factors. ‌

    First, the production cost of PCB boards is affected by materials, design and manufacturing complexity, precision and quality, and supply chain and regional differences. PCB boards are mainly made of materials such as copper, fiberglass and epoxy resin, and the cost of these materials directly affects the price of PCB boards.

    The complexity of the design and manufacturing process, including pre-processing, image transfer, electroplating, etching, inspection and trimming, and post-processing, requires precise tools and professional skills, which will also be reflected in the cost. High-precision PCB boards require higher manufacturing costs because they require more precise tools and more stringent manufacturing processes.

    Details in the PCB assembly process, layer selection, and the application of HDI technology will all have an impact on the cost. Every small change may cause the cost to plummet, so if you want to save money without losing performance, you need to consider these factors comprehensively.

    In addition, the welding process is also a costly link. Soldering is a key step in fixing electronic components to PCBs. This process requires heating each joint separately for welding, which is a slow and laborious process.

    Finally, the price of PCBs is also affected by factors such as materials, surface processing, design standards, copper foil thickness, quality acceptance standards, and mold fees and test frames. For example, different materials, surface processing, and copper foil thickness will lead to price differences.

    In summary, the high cost of PCB assembly is mainly due to the combined effect of multiple factors such as material cost, manufacturing complexity, precision and quality requirements, production needs, and specific design and quality requirements.

    What does PCB stand for?

    PCB stands for Printed Circuit Board. ‌

    What is a PCB assembly?

    Printed circuit board (PCB), also known as printed circuit board, is an indispensable component in electronic engineering. It is the support of electronic components and also the carrier of electrical connection of electronic components.

    Printed circuit boards are widely used in various electronic devices. Printed circuit boards can be divided into single-sided boards, double-sided boards, multi-layer boards, etc. according to the number of layers of circuit boards. Among them, multi-layer boards refer to printed boards with more than two layers. It consists of connecting wires on several layers of insulating substrates and pads for assembling and welding electronic components. It has the function of conducting each layer of circuits and insulating each other.

    The wide application of printed circuit boards makes it possible to miniaturize and visualize the circuits of electronic devices, which plays an important role in the mass production of fixed circuits and optimizing the layout of electrical appliances. This type of circuit board uses polyimide or polyester film as the substrate, and has the characteristics of high wiring density, light weight, thin thickness and good bendability.

    What is the difference between PCB and PCBA?

    The main difference between PCB and PCBA lies in their definition, function, application and manufacturing process. ‌

    Definition:

    PCB (printed circuit board) is a basic electronic component made by electronic printing, mainly used as a support for electronic components, and does not contain any active or passive components.

    PCBA (printed circuit board assembly) is a circuit board assembly with specific functions formed by soldering electronic components to PCB through processes such as SMT (surface mount technology) or THT (through-hole mounting technology). PCBA contains PCB and all necessary electronic components, which work together to realize the preset functions of the circuit board.

    What is a PCB assembly?

    ‌Function and application‌:

    The main function of PCB is to support and connect electronic components, while PCBA integrates electronic components into a complete circuit system, which can be used in the manufacture of various electronic products.

    PCBA is the core part of electronic products and directly determines the performance and function of the product.

    ‌Manufacturing process‌:

    The manufacturing process of PCB includes circuit design, PCB board design, PCB template production, copper foil etching, drilling, tin spraying and board making.

    The production of PCBA requires component mounting, welding, testing and other processes.

    In summary, the main difference between PCB and PCBA lies in their definition, function, application and manufacturing process. PCB is a basic electronic component, mainly used to support and connect electronic components, while PCBA is a finished product formed by welding electronic components to PCB. It has specific circuit functions and is an indispensable part of electronic products.

    What is the difference between PCB manufacturing and assembly?

    The main difference between PCB manufacturing and assembly is that they involve different processes and focuses. ‌

    ‌PCB manufacturing‌ mainly involves the process of converting raw materials into printed circuit boards through a series of process flows, including design, layout, etching, lamination, drilling, welding and other steps, and finally forming a complete and usable printed circuit board.

    ‌PCB assembly‌ is the process of soldering electronic components to the printed circuit board according to the design requirements after the PCB is manufactured. The focus of assembly is to ensure that all components are in the correct position and direction, the pins of each component are fully soldered to the designated pads, and there is no excess solder or other excess materials to ensure the normal operation and reliability of the circuit board.

    In short, ‌manufacturing‌ covers the entire production process from raw materials to finished products, including design, production and testing, while ‌assembly‌ is a link in the manufacturing process that focuses on accurately mounting electronic components on printed circuit boards to ensure the final function and performance of the product.

    Conclusion:

    PCB assembly is an important part of manufacturing and affects the quality of the final product. Therefore, choosing the right manufacturer becomes particularly important. BEST Technology is committed to becoming the world’s most trusted one-stop electronic circuit solution provider, while focusing on PCBA prototyping and small batch production. Choosing us will get the best quality products.

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    what is glass transition temperature?
    Wednesday, August 21st, 2024

    In the PCB manufacturing process, the glass transition temperature is an important performance indicator. During the manufacturing and use of PCB boards, they will undergo multiple heating and cooling processes. If the operating temperature exceeds the glass transition temperature, the board will soften, expand, or even deform, affecting the accuracy and reliability of the circuit. Therefore, choosing the right glass transition temperature is crucial to ensure the dimensional stability and long-term performance of the PCB.

    What is the glass transition temperature and Its Significance?

    The glass transition temperature (Tg) refers to the temperature corresponding to the transition from the glass state to the high elastic state. The glass transition is an inherent property of amorphous polymer materials and a macroscopic manifestation of the transformation of the polymer motion form. It directly affects the performance and process performance of the material. Therefore, it has long been the main content of polymer physics research.

    what is glass transition temperature?

    The glass transition temperature is of great significance to the application of polymers. Above this temperature, polymers show elasticity; below this temperature, polymers show brittleness. This characteristic must be considered when used as plastics, rubber, synthetic fibers, etc.

    The glass transition temperature of mainstream FR-4 boards is approximately between 130-140℃. In the PCB manufacturing process, the temperature needs to be strictly controlled to avoid exceeding the glass transition temperature to ensure the quality of the product.

    Is higher glass transition temperature better?

    In PCB manufacturing, the higher the glass transition temperature (Tg), the better. ‌

    what is glass transition temperature?

    The glass transition temperature is an important performance indicator of polymer materials, which determines the changes in the physical and chemical properties of the material at a specific temperature. When the temperature of the polymer is lower than its glass transition temperature, the material exhibits hard and brittle characteristics, similar to the glass state; when the temperature is higher than the glass transition temperature, the material becomes soft and exhibits elasticity similar to rubber or leather. This state change has a direct impact on the performance during PCB manufacturing and use.

    1. ‌ Temperature deformation resistance ‌:

    The higher the Tg value, the stronger the material’s temperature deformation resistance. This means that in a high temperature environment, such as during SMT welding, the PCB substrate is not easy to deform, thereby maintaining dimensional stability, which is crucial to ensure the reliability and long-term use of the circuit board.

    2. ‌ Electrical performance and mechanical strength: ‌

    The high or low Tg value directly affects the electrical performance and mechanical strength of the PCB. High Tg materials can maintain good physical and chemical stability at high temperatures, thereby maintaining the electrical properties and mechanical strength of the circuit board, which is crucial to improving the quality and reliability of the product.

    3. Safety:

    PCB materials with high Tg values ​​are not easy to soften or melt at high temperatures, thereby improving the safety and durability of the circuit board and reducing the risk of short circuits or other damage caused by high temperatures.

    In summary, choosing PCB materials with higher Tg values ​​is one of the key factors to ensure that the circuit board maintains stable performance and safety in complex manufacturing and use environments.

    What is glass transition temperature vs melting temperature?

    In PCB manufacturing, glass transition temperature and melting temperature are two different physical properties that describe the state changes of materials under different conditions. ‌

    The glass transition temperature (Tg) mainly involves amorphous materials or amorphous regions in partially crystalline materials. At this temperature, the physical state of the material changes from glass to highly elastic.

    The melting temperature (melting point) mainly involves the melting process of crystalline materials. For crystalline polymers, the melting point marks the temperature at which the molecular chain begins to move, that is, the material changes from solid to liquid. The melting point is related to the crystallinity and lattice structure of the material and is a physical property unique to crystalline materials.

    In short, the glass transition temperature mainly affects the amorphous region in amorphous or partially crystalline materials, while the melting temperature mainly affects crystalline materials and involves the melting process of the entire crystal. These two temperatures reflect the different physical state changes of different materials when heated.

    How do you determine the glass transition temperature?

    Expansion method, thermomechanical method, differential scanning calorimetry (DSC), DTA method, dynamic mechanical property analysis (DMA) method, nuclear magnetic resonance method (NMR).

    what is glass transition temperature?

    Differential scanning calorimetry (DSC) is the most traditional and commonly used measurement method. It measures the relationship between the power difference (heat flow rate) and temperature between the sample and the reference material, and then obtains the glass transition temperature of the material;

    Dynamic mechanical analysis (DMA) is the most sensitive method. It measures the sinusoidal alternating stress of constant amplitude applied to the sample, observes the change of strain with temperature or time, and calculates the mechanical parameters to characterize the elastomer;

    Thermomechanical analysis (TMA): Use a probe with good sensitivity to measure the expansion coefficient of the material, and measure the glass transition temperature of the material based on this change.

    What is the difference between TM and Tg?

    In the PCB industry, TM and Tg are two different parameters, representing two different physical properties.

    Tm: melting point; m is the melting point of crystalline polymers, that is, the temperature at which crystalline polymers melt. It is the highest use temperature of crystalline polymers when used in plastics and fibers, and it is also their heat resistance temperature and the lowest temperature for molding processing.

    What is the Tg of polyurethane?

    The glass transition temperature (Tg) of polyurethane is not a fixed value, but a physical quantity determined by the type of resin.

    ‌There are many types of polyurethane, including polyether, polyester, polyimide, polyurea, etc. Each type of polyurethane has its own specific glass transition temperature.

    Shape memory polyurethane has a small volume expansion rate at temperatures below Tg, but increases at temperatures above Tg, which shows the characteristics of its glass transition temperature. Therefore, to determine the glass transition temperature of a specific polyurethane, its specific chemical structure and application field need to be considered.

    What is Tg for epoxy?

    The Tg value of PCB epoxy resin is usually between 130℃ and 170℃. ‌

    The Tg value (glass transition temperature) of PCB (printed circuit board) epoxy resin is an important performance indicator, which reflects the change in the physical state of the material when heated. According to different application requirements, the Tg value of PCB epoxy resin can be divided into several grades:

    what is glass transition temperature?

    ‌TG130‌: The temperature resistance of this type of board is about 140℃. Common Tg value boards of this type are Shengyi S1141 and Jiantao KB-6164F.

    TG150: A medium Tg board with a temperature range of 150°C to 170°C. Common boards with this type of Tg include Shengyi S1141 150 and Jiantao KB-6165F.

    TG170: A high Tg board with a temperature range of over 170°C. Common boards with this type of Tg include Shengyi S1170 and Jiantao KB-6167F.

    Selecting the right Tg value is critical to ensuring the performance and reliability of the PCB. Although boards with high Tg values ​​are relatively expensive, their superior temperature resistance is indispensable in applications that require higher temperatures, such as aerospace. In addition to Tg values, other factors should be considered when selecting PCB boards, such as thermal decomposition temperature (Td), which is another important indicator for evaluating the stability of boards at high temperatures.

    Conclusion:

    High Tg represents high heat resistance. Electronic products represented by computers are developing towards high functionality and high multi-layer, which requires higher heat resistance of PCB substrate materials as an important guarantee. BEST Technology focuses on manufacturing high-performance PCB circuit boards and is far ahead in the industry. It has professional production equipment and 18 years of design experience, and has high quality requirements for products.

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    Let you know about PCB copper layer thickness
    Friday, August 16th, 2024

    In the printed circuit board industry, the most common way to express the copper layer thickness on a PCB is in ounces (oz). 1oz means 1oz of copper evenly covers an area of 1 square foot, which is about 1.4mil. It uses the weight of the tissue area to express the average thickness of the copper foil. Expressed in terms of formula, 1oz=28.35g/FT2 (FT2 is square feet, 1 square foot = 0.09290304 square meters).

    What is the standard thickness of a copper layer on a PCB?

    In the manufacture of printed circuit boards (PCBs), the thickness of the copper layer is an important parameter that directly affects the electrical performance and reliability of the circuit board. Depending on the application requirements, the thickness of the copper layer can vary within a certain range. Generally speaking, the conventional copper layer thickness is between 1-35μm, with 35μm being the most commonly used thickness. For some applications with high reliability requirements, the copper layer thickness may reach more than 50μm.

    The selection of the thickness of the copper layer is a decision-making process that takes into account a variety of factors, including the conductivity, heat dissipation, mechanical strength, cost and manufacturing difficulty of the circuit board. A larger copper thickness can reduce resistance and improve the conductivity and heat dissipation of the circuit board, but it will also increase material costs and production difficulties. Therefore, when designing PCB boards, engineers need to select a suitable copper thickness standard range based on specific application scenarios and design requirements to ensure the performance and reliability of the circuit board.

    1oz copper thickness in mm = 0.035mm

    0.5 oz copper thickness in mm = 0.0175mm

    1.5 oz copper thickness in mils = 0.0525mm

    2 oz copper thickness in mils =  0.07mm‌

    How thick is PCB copper after plating?

    PCB printed circuit boards are usually bonded to glass epoxy substrates with a layer of copper foil, usually 18, 35, 55 and 70 microns thick. The most commonly used copper foil is 35 microns thick.

    The copper foil used by PCB manufacturers is generally 35~50 microns thick, and some are thinner than this, such as 10 microns, 18 microns, and thicker such as 70 microns. The thickness of the composite copper foil on a 1~3 mm thick substrate is about 35 microns. The thickness of the composite copper foil on a substrate with a thickness of less than 1MM is about 18 microns, and the thickness of the composite copper foil on a substrate with a thickness of more than 5 mm is about 55 microns.

    The copper layer thickness of PCB (printed circuit board) can be adjusted according to different needs and designs. Common copper layer thicknesses include 1oz (35μm), 2oz (70μm), 3oz (105μm), and other thicker options. For most applications, a copper layer thickness of 1oz is sufficient and suitable for general signal transmission. ‌For circuit boards that need to carry large currents, such as switching power supplies, a copper layer thickness of 2oz or higher is usually used. ‌In addition, there are some special cases where manufacturers provide extremely heavy copper up to 20 oz/ft2 (26.8 mils or 0.34 mm) to meet special needs. ‌

    When choosing the thickness of the copper layer, factors such as the purpose of the circuit board and the magnitude of the signal voltage and current need to be considered. ‌For example, for circuit boards that require excessive current, a copper thickness of 70μm or 105μm may be used. ‌For thin laminates that require ultra-high density patterns, a copper thickness of 12μm may be used. ‌Therefore, the specific thickness of the PCB after copper plating is determined according to design requirements and specific applications.‌

    How thick is 2 oz copper for PCB?

    If 1 ounce (28.35 grams) of copper were flattened to evenly cover a surface area of 1 square foot (0.093 square meters), the resulting thickness would be 1.37mils (0.0348mm). A conversion chart for different units of measurement can be found below.

    PCB copper layer thickness 

    What is the difference between different copper thicknesses in PCB?

    ‌Copper is an excellent conductive material, and the thickness of the copper layer directly affects the conductive effect of the circuit board. ‌Thicker copper layers can provide lower resistance, reduce signal transmission losses, and are particularly suitable for high-frequency and high-speed digital circuits. ‌

    During the operation of electronic equipment, good heat dissipation is a key factor in ensuring the performance and life of components. ‌Thicker copper layers can conduct and dissipate heat more effectively, preventing components from overheating. ‌

    In high-power electronic devices, thicker copper layers can carry larger currents, avoiding burnout or performance degradation caused by excessive current.

    Below is the conductivity corresponding to different copper thicknesses.

    PCB copper layer thickness 

    How thick is high current PCB copper?

    In PCB design, copper thickness (also called copper thickness) is an important parameter, which directly affects the performance indicators of the circuit board such as current carrying capacity, heat dissipation and reliability. For PCBs that need to withstand high currents, such as high-power LED light strips, power circuit boards, high-power motor control boards or high-power inverter control boards, thicker copper layers are usually used to increase current carrying capacity.

    PCB copper layer thickness 

    Different uses have different copper foil thicknesses. Common 0.5oz, 1oz, and 2oz are mostly used in consumer and communication products. Thick copper products above 3oz are mostly used for high currents, such as high-voltage products and power boards.

    The thickness of copper foil (track width) will affect the current size. Although there is a formula that can directly calculate the maximum current carrying capacity of copper foil, it is not so simple when actually designing the circuit. Therefore, the safety factor should be fully considered during the design.

    How thick is the copper in a flex PCB?

    The thickness of copper foil in flexible PCB is generally 18μm, 35μm, 55μm and 70μm. These thickness specifications are suitable for different types of circuit board requirements, among which 35μm is the most commonly used copper foil thickness.

    PCB copper layer thickness 

    For flexible PCB, the choice of copper foil thickness depends on the specific purpose of the circuit board and the size of the signal voltage and current. For example, for PCBs that require excessive current, some parts will use 70μm copper thickness, while for signal transmission, 1oz (35μm) thickness is usually sufficient. In addition, for substrates of different thicknesses, the thickness of copper foil is also different. For example, the thickness of the composite copper foil on a 1mm thick substrate is about 18μm, and on a substrate thicker than 5mm, the thickness of the composite copper foil is about 55μm.

    Conclusion:

    PCBs for different usage scenarios correspond to different thicknesses of copper, and its thickness directly affects the conductive effect of the circuit board. If the copper layer is too thin, the conductivity may decrease, resulting in signal transmission attenuation or current instability. If the copper layer is too thick, although the conductivity will be very good, it will increase the cost and weight of the circuit board and easily lead to serious glue flow. In PCB manufacturing, it is necessary to select the appropriate copper thickness according to the design requirements and actual applications of the circuit board to achieve the best conductive effect.

    BEST Technology is a professional PCB circuit board manufacturer with a large area of site and equipped with useful and experienced production personnel. Corresponding to different thicknesses of copper, we have rich production and processing experience. We can meet the requirements of any circuit board copper layer thickness.‌

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    What is SMT Process in PCB Manufacturing? – Best Technology
    Wednesday, August 14th, 2024

    SMT process is one of the most commonly used processes in PCBA or box build assembly products. It also called surface mount process. It is reliable connection between electronic components and printed circuit boards can be realized through the precise mounting and welding technology of the SMT machine.

    What is an SMT Process?

    The SMT process is a method used to mount electronic components directly onto the surface of a printed circuit board (PCB). Unlike traditional through-hole technology, where components are placed in drilled holes, SMT components are placed on the board’s surface.

    SMT enables the creation of smaller devices without compromising performance. By eliminating the need for drilled holes, it also speeds up production, reducing costs and improving efficiency.

    What is SMT Process in PCB Manufacturing? - Best Technology

    What is the Purpose of SMT?

    The primary purpose of SMT is to streamline the manufacturing process while enhancing the functionality and reliability of electronic devices. SMT allows manufacturers to produce smaller, more complex circuits that are essential for today’s technology-driven world. From smartphones to medical devices, SMT plays a critical role in the development of products that we rely on daily.

    Moreover, SMT offers flexibility in design, allowing engineers to create intricate circuits that would be impossible with traditional methods. The process also supports higher levels of automation, reducing the risk of human error and ensuring consistent quality across large production runs. In essence, SMT is about improving efficiency, quality, and innovation in electronics manufacturing.

    Terms Related to SMT

    Solder Paste

    A mixture of powdered solder and flux used to bond SMT components to the PCB. It’s applied to the board using a stencil and is essential for creating strong, reliable connections.

    Pick and Place Machine

    An automated machine that picks up components and places them onto the PCB with high precision. This machine is vital in ensuring that components are positioned accurately before soldering.

    Reflow Oven

    After the components are placed on the PCB, the board is passed through a reflow oven. The heat melts the solder paste, securing the components in place.

    Stencil

    A metal or plastic template used to apply solder paste to specific areas of the PCB. The stencil ensures that the paste is only applied where needed, preventing defects.

    Flux

    A chemical agent that cleans the surfaces of the components and the PCB, ensuring a strong bond during the soldering process.

    PCB

    The bare board without any components on its surface. The board that serves as the foundation for electronic components. It has conductive pathways that connect the components and allow them to function together.

    PCBA

    When a PCB is surface-mounted or through-hole-mounted with components, we call this semi-finished product a PCBA. It can further assemble with other PCBAs and an enclosure to become a complete product or box-build we call it.

    SMD

    Surface mount device, it is an electronic component for SMT manufacturing. Compared with PTH components for PTH assembly, SMDs have a much smaller weight and size about 1/10 of a PTH component of the same function.

    How Many Steps are in the SMT Process?

    The SMT process involves several detailed steps, each essential for ensuring the quality and reliability of the final electronic product. Below is a comprehensive look at these steps:

    Step 1: Components Incoming Inspection

    Before the assembly begins, all components undergo an incoming inspection. This step is crucial to ensure that all parts meet the required specifications. It helps in identifying any defects or discrepancies in the components, which could affect the final product’s quality.

    What is SMT Process in PCB Manufacturing? - Best Technology

    Step 2: PCB Quality Control

    The next step is to inspect the PCB itself. This involves checking for any manufacturing defects, such as scratches, misalignments, or irregularities in the copper layers. Ensuring the PCB is flawless is vital because any defect can lead to failure in the final assembly.

    Step 3: Stencil Preparation

    Stencil preparation is critical for the accurate application of solder paste. The stencil must be aligned correctly with the PCB to ensure the solder paste is applied precisely to the pads where components will be placed. This accuracy is key to avoiding soldering defects.

    Step 4: Solder Paste Applying

    Solder paste is applied to the PCB through the stencil. The paste contains tiny balls of solder mixed with flux, and it’s applied to the areas where components will be soldered. Proper application of the solder paste is essential for creating reliable solder joints.

    Step 5: SPI (Solder Paste Inspection)

    After applying the solder paste, it’s inspected using SPI (Solder Paste Inspection) equipment. This step checks the volume, height, and position of the solder paste on the PCB. Any deviations from the ideal paste deposit can lead to defects, so this inspection helps ensure consistency and quality.

    Step 6: Pick and Place Components

    The pick and place machine automatically places components onto the PCB. Misplaced components can lead to electrical failures, so this step is critical for the overall success of the process.

    Step 7: Reflow Soldering

    Once the components are placed, the PCB is passed through a reflow oven. The heat in the oven melts the solder paste, creating a solid electrical connection between the components and the PCB. The reflow process must be carefully controlled to avoid overheating or insufficient soldering.

    Step 8: AOI (Automated Optical Inspection)

    After reflow soldering, the board undergoes AOI. This inspection process uses cameras to check for soldering defects, such as bridges, misaligned components, or insufficient solder. AOI helps catch defects early, reducing the chances of failures in the final product.

    Step 9: X-RAY (Only for BGA or Fine-Pitch Components)

    For boards with Ball Grid Array (BGA) or fine-pitch components, an X-ray inspection is performed. This step allows for the inspection of solder joints that are hidden beneath the components, ensuring that they are properly formed and free of defects.

    Step 10: FAI (First Article Inspection)

    The first board produced in a batch undergoes FAI, where it is thoroughly inspected to ensure that all processes and setups are correct. This step serves as a final check before full production begins, helping to confirm that everything is in order.

    Step 11: Function Testing

    The final step in the SMT process is function testing. This involves testing the completed PCB to ensure it functions as intended. Function testing is essential to verify that the board meets the required specifications and operates correctly in its intended application.

    SMT Process Flow Chart

    A flow chart is a visual representation of the SMT process, showing each step in sequence. This chart is essential for understanding how the process works and identifying potential areas for improvement. Here’s a basic flow chart of the SMT process:

    What is SMT Process in PCB Manufacturing? - Best Technology

    How Do I Prepare for SMT?

    Preparing for the SMT process requires careful planning and attention to detail. Here are some tips to help you get ready:

    • Design for Manufacturability (DFM)
    • Material selection
    • Stencil
    • Equipment calibration
    • Quality control
    • Training

    Best Technology – Your Turn-key PCB & PCBA Supplier

    At Best Technology, we offer a range of value-added services, including IC programming, functional testing, conformal coating, thermal aging, and box-build assembly, ensuring you receive fully assembled and ready-to-use electronic products.

    Additionally, you can reduce fabrication costs without compromising on function or quality. If needed, Best Technology can source alternative components with equivalent functions and certifications to replace more expensive parts as well.

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    TDA7294 Amplifier Board: A Comprehensive Introduction
    Tuesday, August 13th, 2024

    The TDA7294 amplifier board is a functional and widely used audio amplifier. It is based on the TDA7294 integrated circuit (IC), a high-power, low-distortion audio amplifier IC developed by STMicroelectronics. This IC is designed to deliver high-quality audio output with minimal distortion, making it a popular choice for DIY audio enthusiasts and professionals alike.

    What is TDA7294 IC Amplifier Board?

    The TDA7294 IC is capable of delivering up to 100 watts of power in a single-ended or bridged configuration, making it suitable for a wide range of audio applications, from home audio systems to professional audio equipment. The amplifier board typically includes the TDA7294 IC along with supporting components such as capacitors, resistors, and heatsinks, all mounted on a printed circuit board (PCB). This board is designed to simplify the process of building a powerful and reliable audio amplifier by providing a pre-configured layout that ensures optimal performance.

    TDA7294 Amplifier Board: A Comprehensive Introduction

    Features of TDA7294 Amplifier Board

    The TDA7294 amplifier board provides several key features that make it a popular choice for high-quality audio amplification.

    • High Output Power
    • Low Distortion
    • Built-in Protection Circuits
    • Thermal Management
    • Low Noise and High Signal-to-Noise Ratio (SNR)
    • Ease of Integration
    • Flexible Configuration
    • Improved Reliability
    • Compact Size

    TDA7294 Amplifier Circuit Diagram

    The circuit diagram of the TDA7294 amplifier is a crucial element for anyone looking to build or understand this amplifier. The diagram typically includes the TDA7294 IC at the core, surrounded by components that shape the audio signal and manage power delivery. Key components include capacitors for signal coupling and power supply smoothing, resistors for setting gain and biasing, and inductors or filters for noise reduction.

    TDA7294 Amplifier Board: A Comprehensive Introduction

    The TDA7294 IC itself has several pins that serve specific functions in the circuit. For instance, the input pin receives the audio signal, while the output pin sends the amplified signal to the speakers. Power supply pins connect to the positive and negative voltage rails, and other pins might be used for muting, standby, or feedback purposes.

    When assembling the circuit, careful attention must be paid to the placement of components and routing of traces on the PCB to minimize noise and maximize performance. The layout of the circuit diagram ensures that the amplifier delivers clean, high-fidelity sound with minimal distortion, which is a key selling point for the TDA7294.

    TDA7294 Specification

    SymbolParameterTest conditionMin. valueTypical valueMax. valueUnit
    VsPower Supply ±10 ±40V
    lqCurrent Consumption 203060mA
    VosInput Offset Voltage   500mV
    losInput Offset Current   ±100nA
    PoContinuous Power OutputVS = ± 35V, RL = 8Ω; VS = ± 31V, RL = 6Ω; VS = ± 27V, RL = 4Ω;  6070 W
    dTHDPO = 5W; f = 1kHz PO = 0.1 to 50W; f = 20Hz to 20kHz 0.0050.01%
    VS = ±27V, RL = 4W: PO = 5W; f = 1kHz PO = 0.1 to 50W; f = 20Hz to 20kHz   0.010.01%
    SRSwitching rate 710 V/us
    GvOpen Loop Voltage Gain  80 dB
    GvClosed Loop Voltage Gain 243040dB
    fL, fHFrequency Response (-3dB)Po=1W20Hz to 20kHz
    RiInput Resistance 100  

    TDA7294 Pinout

    The TDA7294 IC comes with a specific pinout configuration that plays a crucial role in its operation. The chip has 15 pins, each with a designated function:

    TDA7294 Amplifier Board: A Comprehensive Introduction

    Pin 1 (IN+): Non-inverting input

    Pin 2 (SVR): Supply voltage rejection

    Pin 3 (IN-): Inverting input

    Pin 4 (MUTE): Mute function

    Pin 5 (ST-BY): Standby function

    Pin 6 (VCC+): Positive supply voltage

    Pin 7 (OUT): Output

    Pin 8 (GND): Ground

    Pin 9 (BOOTSTRAP): Bootstrap capacitor

    Pin 10 (NC): Not connected

    Pin 11 (VCC-): Negative supply voltage

    Pin 12 (DIAG): Diagnostics pin

    Pin 13 (BOOTSTRAP): Bootstrap capacitor

    Pin 14 (GND): Ground

    Pin 15 (OUT): Output

    TDA7294 Datasheet

    The TDA7294 datasheet is a critical resource for anyone working with this IC. It provides detailed information about the IC’s electrical characteristics, pin configurations, thermal properties, and recommended operating conditions. The datasheet also includes typical application circuits, which can serve as a starting point for designing your own amplifier.

    In addition to technical specifications, the datasheet often includes practical advice on PCB layout, component selection, and thermal management. Following these guidelines can help you achieve the best possible performance from your TDA7294 amplifier board.

    How Many Watts is a TDA7294 Output?

    The TDA7294 IC is capable of delivering up to 100 watts of output power when configured in a single-ended or bridged amplifier circuit. The actual output power depends on several factors, including the supply voltage, load impedance, and heat dissipation. In a typical configuration with a supply voltage of ±35V and an 8-ohm load, the TDA7294 can deliver around 70 watts of continuous power.

    For higher power output, the IC can be used in a bridged configuration, where two TDA7294 ICs are combined to drive a single load. In this setup, the output power can reach up to 150 watts, making it suitable for driving larger speakers or subwoofers.

    It’s important to note that the power rating of the TDA7294 should be matched to the speakers and other components in your audio system. Overloading the IC by driving it at maximum power for extended periods can lead to overheating and potential damage, so proper thermal management is essential.

    What is the Equivalent of TDA7294?

    When looking for an equivalent to the TDA7294, there are a few other audio amplifier ICs that offer similar performance characteristics. Some of the commonly considered alternatives include:

    • LM3886

    This is another high-power audio amplifier IC that delivers up to 68 watts of output power. It’s known for its low distortion and high fidelity, making it a popular choice for DIY audio projects.

    • TDA7293

    This IC is very similar to the TDA7294, with slightly different electrical characteristics. It can be used as a drop-in replacement in many circuits, offering similar power output and performance.

    • TDA2030

    While not as powerful as the TDA7294, this IC is a good alternative for lower-power applications. It delivers up to 20 watts of output power and is widely used in small audio amplifier projects.

    Each of these alternatives has its strengths and weaknesses, so the best choice depends on the specific requirements of your project. For instance, if you need higher output power, the LM3886 might be a better option, while the TDA2030 is more suitable for compact, low-power designs.

    What is the Maximum Voltage for TDA7294 IC?

    The maximum supply voltage for the TDA7294 IC is ±50V. However, for optimal performance and reliability, it’s recommended to operate the IC at a lower voltage, typically around ±35V to ±40V. Operating at the maximum voltage can increase the risk of overheating and may require additional cooling measures, such as larger heatsinks or active cooling.

    The voltage rating is crucial for ensuring the longevity and performance of the amplifier. Exceeding the maximum voltage can cause the IC to fail, leading to permanent damage. Therefore, it’s important to choose a power supply that matches the recommended voltage range for the TDA7294.

    In addition to the supply voltage, the IC’s thermal management is also important. Ensuring adequate cooling through heatsinks or ventilation can prevent overheating and ensure stable operation, especially when driving the amplifier at high power levels.

    What is TDA in an Amplifier?

    The TDA prefix in TDA7294 refers to the series of audio amplifier ICs developed by STMicroelectronics. These ICs are designed to provide high-quality audio amplification with minimal distortion and noise. The TDA series includes a range of ICs with varying power output capabilities, making them suitable for different audio applications, from small portable speakers to large home audio systems.

    In an amplifier, the TDA IC is responsible for amplifying the audio signal from a low-level input to a high-level output that can drive speakers. The IC’s internal circuitry is optimized for audio performance, ensuring that the amplified signal remains clear and distortion-free.

    The TDA series is widely regarded for its reliability and performance, making it a popular choice for both commercial and DIY audio projects. Whether you’re building a simple audio amplifier or a more complex audio system, the TDA7294 and its counterparts offer a solid foundation for high-quality sound.

    FAQs

    1. Can the TDA7294 be used in a car audio system?

    Yes, the TDA7294 can be used in car audio systems, but you need to ensure that the power supply provides the correct voltage and current. Car audio systems typically operate at 12V, so a step-up converter might be needed to reach the required supply voltage.

    2. How do I connect multiple TDA7294 ICs for higher power output?

    You can connect multiple TDA7294 ICs in a bridged configuration to increase the power output. This involves using two ICs to drive a single load, effectively doubling the output power.

    3. What is the typical distortion level of the TDA7294?

    The TDA7294 has a low distortion level, typically around 0.005% at 1kHz, making it suitable for high-fidelity audio applications.

    4. Is the TDA7294 suitable for subwoofers?

    Yes, the TDA7294 is suitable for driving subwoofers, especially in a bridged configuration where it can deliver high power output with low distortion.

    5. Can I use the TDA7294 with a passive cooling system?

    While the TDA7294 can be used with a passive cooling system, it’s important to ensure that the heatsink is large enough to dissipate the heat generated during operation. For higher power levels, active cooling may be necessary to prevent overheating.

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    Rigid flex pcb Design & Prototype Right the First Time
    Monday, August 12th, 2024

    rigid-flex printed circuit board ,Rigid flex pcb manufacturer. More than 5 years design team of 10 people. Quick proofing within 1 week. A 3,000-square-meter factory for small batch to mass production and assembly.

    What is a rigid flex pcb?

    Rigid flex pcb,rigid-flex printed circuit board,Rigid flex circuit are a hybrid construction flex circuit consisting of rigid and flexible substrates which are laminated together into a single structure. Each layer of rigid-flex circuit are electrically interconnected by plated through holes (PTH), which is different from a flexible circuit with FR4/PI stiffener on top or bottom of flex circuit only by the means of presensive or thermal senstive adhesive only, no PTH.

    What is a rigid flex pcb?

    Rigid-flex PCBs can be divided into single-sided boards, double-sided boards and multi-layer boards according to the number of conductive circuit layers. Multi-layer boards usually contain multiple rigid layers and flexible layers, and the circuits are connected and interconnected through interlayer connections.

    Is Rigid flex PCB reliable?

    1. Design and manufacturing efficiency: Designers of rigid-flex boards can use a single component to replace a composite printed circuit board connected by multiple connectors, multiple cables and ribbon cables, which not only has stronger performance and higher stability, but also limits the scope of the design to one component, optimizing the available space by bending and folding the lines like a stacked paper swan.
    2. Space and weight optimization: In PCB prototyping for consumer electronics, the use of rigid-flex boards not only maximizes space use and minimizes weight, but also greatly improves reliability, eliminating many needs for solder joints and fragile and fragile wiring that are prone to connection problems. The design of this circuit board allows the size and weight of equipment and systems to be reduced while maintaining functionality.
    3. High stress environment adaptability: Rigid-flex boards also have high impact resistance and can survive in high stress environments, which makes it widely used in military, aviation and medical equipment.
    4. Excellent electrical performance: Rigid-flex boards provide excellent electrical performance, and good thermal conductivity makes components easy to cool. The lower dielectric constant of the flexible part allows for fast transmission of electrical signals, and the PI substrate has a higher glass transition temperature or melting point, which allows the components to operate well at higher temperatures.
    5. Assembly reliability: Rigid-flex boards reduce the hardware required for traditional rigid boards and flexible boards to be connected, such as traditional jumper sockets, etc., and can provide higher assembly reliability.

    What is the difference between rigid flex and semi flex?

    1. Definition and structure
      Rigid-flexible board: It is a combination of soft board and hard board, that is, a thin layer of flexible bottom layer and rigid bottom layer are combined and laminated into a single component to form a circuit board1. It changes the traditional flat design concept and expands it to a three-dimensional space concept. It has both rigid layer and flexible layer and is a multi-layer printed circuit board.
      Semi-flexible board: It is a PCB used in the field of static bending obtained by combining controlled deep milling or rigid-flexible board processing technology (such as milling cover or opening window, etc.) in the standard hard board processing process2. It often uses FR4 material, first processes the PCB according to the normal process, and then mills the middle part that needs to be bent to make it flexible.
    2. Flexibility and application
      Rigid-flexible board: It has higher flexibility and can be bent, folded or rounded, and then integrated into various products, such as aerospace equipment, military aircraft, high-end medical equipment, digital cameras, portable cameras and high-quality MP3 players. ‌
      Semi-flexible board: Although it can be bent or curved, its flexibility is not as good as that of rigid-flexible board. It is mainly used in situations where static bending is required, such as endoscopes in medical equipment, injection needle tip protection circuit boards, and medical equipment temperature control circuit boards. ‌
    3. Processing and cost
      Rigid-flexible board: Due to the mixed use of multiple materials and multiple production steps, its processing time is longer and the production cost is higher. ‌
      Semi-flexible board: Although its processing process is also more complicated, its processing cost is lower than that of rigid-flexible board, and it is more suitable in some applications. ‌
    4. Features and advantages
      Rigid-flexible board: It has stronger performance and higher stability, can reduce space and weight, and improve the reliability of connection. ‌
    5. Semi-flexible board: It has the advantages of low cost, good dimensional stability, bendable three-dimensional installation to reduce space, and reduce the number of interfaces during assembly to improve reliability.‌

    how do they add rigid layers to flex pcb?

    1. Design layout: Before starting the manufacturing process, the PCB design layout is first carried out to determine the location and connection method of the components. ‌
    2. Substrate preparation: Clean the laminate containing the copper layer to prepare for the subsequent manufacturing process. ‌
    3. Pattern generation: The generation of circuit patterns is completed by screen printing or photo imaging. ‌
    4. Etching process: The laminate with the circuit pattern is soaked in an etching tank or sprayed with an etchant solution for etching. ‌
    5. Mechanical drilling: Circuit holes, pads and via patterns are drilled using a precision drilling system or technology, such as laser drilling technology. ‌
    6. Copper plating process: Deposit the required copper in the plated vias to establish electrical interconnections between layers. ‌
    7. Covering layer application and lamination: Apply the covering layer material (such as polyimide film) and adhesive, and laminate under specific temperature, pressure and vacuum limits to ensure proper adhesion of the covering layer. ‌
    8. Apply stiffeners: Apply local additional stiffeners before additional lamination processes as required by the board design. ‌
    9. Flexible board cutting: Cut flexible boards from production panels using hydraulic punching methods or specialized punching knives. ‌
    10. Electrical testing and verification: Conduct electrical testing in accordance with IPC-ET-652 guidelines to confirm that the insulation, connection, quality, and performance of the circuit board meet the requirements of the design specifications.

    What are the disadvantages of rigid flex PCB?

    1. Material damage or breakage: The flexible materials used in rigid-flex boards are susceptible to flexure and bending. Long-term use or improper handling may cause damage or breakage of the flexible part, resulting in an open circuit.
    2. Poor welding: The manufacture of rigid-flex boards requires welding processes. If the welding is poor or the solder joints are of poor quality, it may cause loose connections or solder joints to fall off, resulting in an open circuit.
    3. Excessive bending or stretching: Excessive bending or stretching during use may cause the connection wires or wires of the flexible part to be stretched excessively and break, causing an open circuit.
    4. Design defects: If the design of the rigid-flex board is unreasonable or defective, such as insufficient design of the overbending area or too small bending radius, the material of the flexible part may be damaged by excessive stress, resulting in an open circuit.
    5. Environmental factors: Under different environmental conditions, it may be affected by factors such as temperature, humidity, and chemicals. Long-term use in harsh environments may cause material aging or corrosion, resulting in an open circuit. ‌
    6. Damage during assembly: During the assembly process, improper operation or external force may cause damage to the connecting wires or wires of the flexible part, resulting in an open circuit.

    Application fields of rigid flex PCB

    1. Automotive electronics: Rigid-flex boards are widely used in automotive electronic systems such as dashboards, navigation systems, and in-car entertainment systems in the automotive industry. Their flexibility and high reliability enable them to adapt to the complex spatial layout and vibration environment inside the car.
    2. Medical equipment: In the field of medical equipment, rigid-flex boards also have important applications, such as medical monitoring equipment, medical imaging equipment, etc. Its flexible part can adapt to different equipment shapes and size requirements, while having stable circuit connection performance.
    3. Aerospace field: Rigid-flex boards are usually used in aircraft dashboards, navigation systems, communication equipment, etc. in the aerospace field. Due to their light, thin and flexible characteristics, rigid-flex boards have become an ideal choice for aerospace equipment.
    4. Smart wearable devices: With the rapid development of smart wearable devices, rigid-flex boards are widely used in products such as smart watches and health monitoring equipment. They can be combined with curved display screens, sensors and other components to achieve a more humanized design.
    5. Industrial control field: In the field of industrial automation control, rigid-flex boards are often used in PLC controllers, robot control systems, sensor interfaces, etc. Its flexibility and reliability ensure the stable operation of the equipment in harsh environments.
    Application fields of rigid flex PCB

    Rigid flex pcb manufacturer

    rigid flex pcb.rigid-flex printed circuit board,Rigid flex circuit are a hybrid construction flex circuit consisting of rigid and flexible substrates which are laminated together into a single structure. Each layer of rigid-flex circuit are electrically interconnected by plated through holes (PTH), which is different from a flexible circuit with FR4/PI stiffener on top or bottom of flex circuit only by the means of presensive or thermal senstive adhesive only, no PTH.

    Rigid flex pcb manufacturer

    Multilayer circuitry-from 3 to 14+ layers
    Min LW/LS: 4mil/4mil
    Adhesive-based and adhesiveless constructions, including thermoplastic and thermoset stiffener attachment.
    Polyimide substrates: 1/2mil – 4mil
    Copper: 1/3OZ – 2OZ, RA or ED type
    Stiffeners include Polyimide (0.075-0.20mm), FR4 (0.15-2.0mm), and punched or formed metal parts (0.075-1.0mm)
    Low-cost, conventional fabrication and lamination completed with PTH based plating
    Screened inks, photo-imageable soldermasks, or laminated coverlay dielectrics
    Surface finishes: ENIG, electroplated nickel/gold, immersion silver, tin,
    EMI Shielding

    how to design flex rigid pcb?

    Rigid-Flex Circuit Design Guidelines

    To form a rigid-flex, follow these considerations to ensure the best results.

    Considerations When Designing Rigid-Flex Circuits

    To produce a rigid-flex PCB with unmatched quality and functionality, you must follow the correct manufacturing specifications. This is the set guidelines and standards that manufacturers must consider when designing and manufacturing flexible circuit boards.

    Determine Manufacturing Process and Materials Beforehand

    Depending on the flexibility you require, you need to decide beforehand what materials to use and the methods to use. Example; When the board you are designing only needs to be folded during manufacturing and thereafter be in a fixed position without bending, you can decide the following

    1. Copper type and grade
    2. Manufacturing method
    3. Number of layers to be used.

    On the other hand, if the board is for an application with frequent movement, vibration, and impact, you must be clear in choosing the following:

    1. Copper Coils
    2. Adhesives and
    3. Number of Layers

    Place Copper Traces at Right Angles to Rigid-Flex

    Copperworks is a great fit when placed on the right edge of the board. Avoid bending copper traces at corners as it will pull stress and may not create the best bend. For PCB flex that requires bending, use sharp radius bends to avoid smudging copper traces.

    Provide adequate pad support for exposed copper

    Repetitive stress from frequent bending can cause copper on the circuit to break away from the polyimide substrate. Support exposed copper with pads to prevent separation.

    Use hatched polygons

    Hatched polygons instead of solidified copper help maintain the flexibility of flexible PCBs.

    Leave at least 1/2mm gap between copper ring and adjacent vias

    1/2mm helps avoid fatigue caused by frequent bending. Placing vias in fixed areas of the board helps avoid frequent movement and bending, resulting in the best rigid-flex.

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