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PWB Vs. PCB: What Are the Manufacturing Process Differences?
Thursday, July 4th, 2024

In our daily life, electronic devices are existing everywhere. And there are many people know the “PCB” nowadays, while very less people know the “PWB”. Unless you’ve been in the PCB business for more than 20 years.

Actually, PWB is another term of circuit board, and it was used commonly before the year 1999. But with the development of electronics, it was replaced by PCB gradually. You want to know more about it? In this article, we will answer it for you. Deeply explain their definitions, manufacturing process, applications and the key differences between PCB and PWB.

PWB Vs. PCB: What Are the Manufacturing Process Differences?

What is A Printed Circuit Board (PCB)?

A Printed Circuit Board is a fundamental component in modern electronics, providing the physical and electrical connections for various electronic components. It consists of multiple compositions, including a non-conductive substrate, conductive pathways, and insulating layers, which facilitate the complex circuitry required in contemporary devices. A PCB can be made into single sided PCB, double sided PCB and multilayer PCB.

PCBs are integral to the functionality of a wide range of electronic products, from consumer gadgets like smartphones and computers to industrial machinery, medical devices, and aerospace systems. The advanced design and manufacturing processes involved in PCB production ensure high reliability and performance, making them essential in virtually all electronic applications.

PWB Vs. PCB: What Are the Manufacturing Process Differences?

Basic manufacturing process of PCB

Design and Layout

PCBs are designed using sophisticated computer-aided design (CAD) software. Designers create detailed layouts, specifying the placement of components, conductive pathways, and vias (interlayer connections). The design is converted into Gerber files, a standard format for PCB fabrication that contains all the necessary information for manufacturing. These files are essential for ensuring precision and accuracy during the manufacturing process.

Material Preparation

The substrate, typically FR4 (fiberglass epoxy laminate), is prepared. FR4 is known for its excellent mechanical strength and thermal stability, making it an ideal base material for PCBs. Copper sheets are laminated onto the substrate, which will form the conductive pathways after the etching process. This preparation stage is crucial for creating a reliable foundation for the PCB.

Printing the Circuit Pattern

A photoresist, a light-sensitive material, is applied to the copper-clad substrate. The board is exposed to ultraviolet (UV) light through a mask that defines the circuit pattern. The UV light hardens the photoresist in the exposed areas. The board is then developed in a chemical solution that removes the unexposed photoresist, revealing the copper to be etched away. This step accurately transfers the circuit design onto the board.

Etching

The board is immersed in an etching solution, commonly ferric chloride or ammonium persulfate, which removes the unprotected copper, leaving only the desired circuit pattern. This etching process is crucial for defining the conductive pathways on the PCB, ensuring that the correct connections are made according to the design specifications.

Drilling

Precision drilling machines are used to create holes for through-hole components and vias. These holes are then cleaned to remove any debris that could affect electrical connectivity. Drilling is a critical step in the PCB manufacturing process as it ensures proper placement and connection of components across different layers of the board.

Plating

The drilled holes are plated with copper to create electrical connections between the layers, which is especially important for multilayer PCBs. Additional layers of plating, such as nickel or gold, may be applied to improve conductivity and protect against oxidation. This plating process enhances the durability and performance of the PCB.

Solder Mask Applying

A solder mask is applied to protect the copper traces from oxidation and prevent solder bridges between closely spaced solder pads. The solder mask is exposed to UV light and then developed to reveal the solder pads. This layer not only protects the PCB but also improves its appearance and reliability.

Silkscreen Printing

A silkscreen layer is printed on the board to add text, component labels, and other identifiers. This layer helps in the identification and assembly of components, making it easier for technicians to work with the PCB during the manufacturing and repair processes.

Surface Finishing

Generally, a layer of surface finishing is coated on the PCB to protect its surface, it also called surface treatment. The common surface treatments are HASL-LF, ENIG, ENEPIG, OSP, Immersion Silver/Tin. Of course, different treatment offers different function, like OSP is to protect surface from oxidation, HASL-LF provides a good solderability, ENEPIG make sure the chemistry corrosion. Choose a suitable one according to your specific demands.

Assembly and Testing

Components are placed on the board using automated pick-and-place machines, and soldered using techniques like reflow soldering for surface-mount devices (SMD) and wave soldering for through-hole components. The finished PCB undergoes various tests, such as automated optical inspection (AOI), electrical testing, and functional testing, to ensure quality and performance. Want see the whole manufacturing process of a multilayer PCB, click here: Manufacturing Process of Multi-layer PCB.

PWB Vs. PCB: What Are the Manufacturing Process Differences?

What is the definition of Printed Wiring Board (PWB)?

A Printed Wiring Board is a term historically used to describe a type of circuit board that focuses primarily on the layout and wiring of electronic connections rather than the overall circuit functionality. PWBs emphasize the physical arrangement of conductive paths to connect various components but do not necessarily include all the integrated features found in modern PCBs.

PWB Vs. PCB: What Are the Manufacturing Process Differences?

This term was more prevalent during the earlier stages of electronic development, where the primary concern was establishing reliable electrical connections. As technology advanced, the term PCB became more common, reflecting the expanded capabilities and comprehensive role of these boards in forming complete electronic circuits. Despite being less common today, understanding the term PWB is crucial for historical context and certain niche applications.

How to Manufacture A Printed Wiring Board (PWB)?

Design and Layout

PWBs typically have simpler designs focused on wiring patterns rather than complex circuitry. In some cases, the layout may be done manually or using basic design software.

Material Preparation

Simpler substrates such as phenolic or epoxy resins may be used for PWBs. Copper sheets are laminated onto the substrate to form the conductive pathways. These materials are cost-effective and suitable for applications where advanced performance characteristics are not required.

Printing the Wiring Pattern

Similar to PCBs, a photoresist is applied to the copper-clad substrate. The board is then exposed to UV light through a mask and developed to reveal the copper to be etched away. This process creates the wiring pattern necessary for connecting electronic components.

Etching

The board is immersed in an etching solution to create the wiring pattern. This step is straightforward compared to the more intricate etching processes used in PCB manufacturing, reflecting the simpler requirements of PWBs.

Drilling

Holes for through-hole components are drilled, but the process may not require the precision needed for complex PCBs. This basic drilling process is adequate for the less demanding applications of PWBs.

Plating (if necessary)

Plating is done to ensure electrical connectivity but may not involve advanced techniques like those used for multilayer PCBs. It suffices for the simpler construction of PWBs.

Solder Mask Application

A basic solder mask may be applied to protect the wiring pattern. This layer provides sufficient protection for the relatively simple designs of PWBs, preventing short circuits and oxidation.

Silkscreen Printing

A simple silkscreen layer may be added for component identification. This helps in the assembly process but does not require the detailed labeling often necessary for PCBs.

Assembly and Testing

Components are manually or semi-automatically placed on PWBs and soldered using standard techniques. Basic electrical testing is conducted to ensure functionality. This simpler assembly and testing process aligns with the less complex nature of PWBs.

pcb assembly

Which Kind of Materials used in PCB and PWB?

Substrate Materials

FR4 (fiberglass epoxy laminate) is the most common substrate material for PCBs due to its excellent mechanical strength and thermal stability. Phenolic resin, used in PWBs for simpler applications, is less durable and has lower thermal stability compared to FR4, but it is cost-effective and suitable for basic electronic devices. Polyimide is used for flexible PCBs due to its high flexibility and thermal resistance, making it ideal for applications requiring bending and flexing, such as wearable electronics and flexible displays.

Conductive Materials

Copper is the primary conductive material for both PCBs and PWBs. It is used to create the conductive pathways and pads, providing excellent electrical conductivity and reliability. Gold, nickel, and silver are used for plating to enhance conductivity and protect against oxidation, primarily in PCBs. These materials improve the durability and performance of the PCB by providing a reliable contact surface for soldering and component connections.

Insulating Materials

Prepreg, a fiberglass cloth impregnated with resin, is used in multilayer PCBs to bond the layers together. Prepreg provides mechanical strength and electrical insulation between the layers. Dielectric materials are used between layers in multilayer PCBs to provide electrical insulation, maintaining signal integrity and preventing short circuits.

Solder Mask Materials

Liquid Photo Imageable (LPI) solder mask is the most common type used in PCBs, providing excellent protection and durability. LPI solder masks are applied using a photolithographic process, ensuring precise coverage and protection. Dry film solder mask is used for simpler applications and PWBs. This type of solder mask is less expensive and easier to apply but may not offer the same level of protection as LPI solder masks.

Key differences between PCB and PWB

FeaturePCB (Printed Circuit Board)PWB (Printed Wiring Board)
Design and LayoutDesigned using sophisticated CAD tools for complex circuitry, including detailed simulation and optimization.Simpler designs focused on wiring patterns, often done manually or with basic software.
Layer CountCan have multiple layers (e.g., double-sided, multilayer) to support intricate circuit designs.Generally single or double-sided, less commonly multilayer.
Component TypesSupports surface-mount technology (SMT) and through-hole technology (THT) components.Primarily supports through-hole technology (THT) components.
Signal IntegrityDesigned to maintain high signal integrity, minimizing electrical noise and interference.Basic signal integrity management, sufficient for simple applications.
Flexibility and RigidityIncludes both rigid and flexible PCBs, allowing for a wide range of applications.Typically rigid, not commonly used in flexible applications.
Terminology and UsageUniversally used in the industry to refer to boards that integrate all necessary components to form complete circuits. Also called “bare board”.Universally used in the industry to refer to boards that integrate all necessary components to form complete circuits.
Industry StandardsRecognized by standards organizations like IPC, IEC, and ANSI with specific performance and quality criteria.Covered under broader standards but with fewer specific guidelines due to limited modern use.
Cost and EfficiencyHigher cost due to advanced materials and processes, offering superior performance and reliability.More cost-effective for simple applications, but with limited performance and reliability.
ApplicationsUsed in consumer electronics, industrial equipment, medical devices, aerospace, and defense.Historically used in simpler electronic devices and early computers, still relevant in niche applications.
(Summary Differences: PCB VS PWB)

Other Terms Related to PWB and PCB

Based on the PCB and PWB, you may still hear about CCA, PCA, PWA during the PCB working. These terms are also related to printed circuit board. Here is a detailed explanation of each:

Printed Wiring Assembly (PWA)

PWA is the abbreviation for printed wiring assembly. This is an archaic term that was once used to describe what we now refer to as PCB assembly or PCBA. Although it is less common today, understanding this term is useful for historical context and when dealing with older documentation.

Circuit Card Assembly (CCA)

CCA stands for circuit card assembly. It is essentially the same thing as PCBA, where the PCB is assembled with all necessary components to create a functional unit. CCA is a less frequently used term compared to PCBA but is still recognized in certain industries and contexts.

Printed Circuit Board Assembly (PCBA)

PCBA is the abbreviation for printed circuit board assembly. When the PCB is assembled with all its electronic components by SMT technology, it is called PCBA or PCB assembly. Since a change in terminology in 1999, PCBA has become the standard term used for all assembled circuit boards. From users to technical committees, PCBA is the preferred term for referring to assembled boards. The assembly process involves placing and soldering components onto the PCB, making it a functional electronic circuit.

Printed Circuit Assembly (PCA)

PCA stands for printed circuit assembly, which is another term for PCBA. Like CCA, PCA is not commonly used in modern terminology but refers to the same concept of an assembled printed circuit board.

aging test of PWB boards

In a word, whatever for PWB, PCB, or circuit cards, they are refer to bare printed circuit boards (bare boards). While PCA, CCA, PWA, and PCBA refer to assembled circuit boards. Among these terms, PCB and PCBA are the most widely used in both industry and technical documentation.

This is the end of this introduction of PWB and PCB, welcome to contact us if you want more about PCB knowledge.

What Are the Differences Between Active and Passive Components?
Wednesday, July 3rd, 2024

In PCB electronics, components are classified into two main categories: active and passive components. Understanding these differences is crucial for anyone working with electronic circuits. Active components control electricity flow and require an external power source. Passive components do not control electricity and do not need an external power source.

What are active and passive components meaning?

Active and passive components, simply say, the device that needs an energy (electrical) source is called an active device, and the device that does not need an energy source is a passive device. Active components, such as transistors and diodes, require external power to function. They can control the flow of electricity. Passive components, like resistors and capacitors, do not need external power. They cannot control electrical flow but can store, resist, or filter energy. Both passive and active components are common useful in PCB assembly and SMT technology.

Active components play a dynamic role in circuits. They can amplify signals, switch currents, and perform various complex functions. These components rely on an external power source to operate and influence the behavior of the circuit. For instance, a transistor can amplify a weak signal, making it stronger and more useful for further processing.

What Are the Differences Between Active and Passive Components?

Passive components, on the other hand, are more static in nature. They cannot amplify signals or control current flow but are essential for other functions like energy storage and signal filtering. Resistors, capacitors, inductors, and transformers are common examples. Each of these components has a specific role in maintaining the stability and functionality of an electronic circuit.

What are the key differences between active and passive components?

The main difference between active and passive components is their ability to control electricity. Active components can amplify signals and perform complex tasks. Passive components can only store, resist, or filter energy. They cannot amplify signals or control current.

Active components are energy-dependent. They require an external source of power to function and can influence the flow of electricity within the circuit. For example, an integrated circuit (IC) can perform multiple functions like amplification, switching, and signal modulation, all of which require external power.

Passive components, in contrast, do not require an external power source. They can only perform their functions passively. For instance, a resistor can limit the current flowing through a circuit without needing additional power. Similarly, a capacitor can store electrical energy and release it when needed, all without external energy input.

Common active components in electronics

Active devices are the main components of electronic circuits. From the physical structure, circuit function and engineering parameters, active devices can be divided into discrete devices and integrated circuits.

1. Discrete devices

  • Bipolar transistor, generally referred to as transistor or BJT
  • Field effective transistor
  • Thyristor
  • Semiconductor resistors and capacitors – resistors and capacitors manufactured by integrated technology are used in integrated circuits.

2. Integrated circuit

Integrated circuit can be divided into analog IC and digital IC. Analog integrated circuits mainly deal with continuous analog signals, such as sound, light, temperature, etc., and retain the continuity and accuracy of the signal through amplification, filtering, mixing and other operations. In contrast, digital integrated circuits are used to process discrete time digital signals, convert the signal into binary digital form, and then perform logical operations and processing.

Basic analog integrated circuit devices generally include:

  • Integrated operational amplifier (operation amplifier)
  • Comparator
  • Logarithmic and exponential amplifiers
  • Multiplier/divider
  • Analog switching circuit (analog switch)
  • Phase lock loop
  • Integrated voltage regulator
  • Reference source
  • Wave-form generator
  • Power amplifier

Digital integrated circuit including:

  • Logic gate circuit
  • Flip-flop
  • Register
  • Decoder
  • Data comparator
  • Driver
  • Counter
  • Shaping circuit
  • Programmable Logic Device (PLD)
  • Microprocessor (MPU)
  • Microcontroller (MCU)
  • Digital signal processor (DSP)

Common passive components in electronics

Passive devices in electronic systems can be divided into circuit components and connection components according to the circuit functions they play. These components are essential for functions like energy storage, filtering, and impedance matching in electronic circuits. The common passive components are including:

Circuit components

  1. Diode
  2. Resistor
  3. Resistor network
  4. Capacitor
  5. Inductor
  6. Transformer
  7. Relay
  8. Key
  9. Speaker
  10. Switch

Connection components

  • Connector
  • Socket
  • Cable
  • PCB (printed circuit board)

Why are active components crucial in modern electronics?

The ability of active components to control and manipulate electrical signals makes them indispensable in a wide range of applications.

In computers, for example, active components such as processors and memory chips perform complex calculations and store large amounts of data. In communication systems, active components amplify weak signals, making long-distance transmission possible. Without these amplifiers, the signal would decay with distance, leading to a decline in communication quality. Power electronics, another key area of modern development, relies heavily on active components. Devices like power converters, inverters, and motor controllers use transistors and integrated circuits to efficiently convert and control electrical energy. This efficiency is crucial for applications ranging from renewable energy systems to electric vehicles.

It’s fair to say that without active components, devices like computers, smartphones, and TVS wouldn’t function the way they do today, and our era of big data wouldn’t be moving as fast as it is today.

How do passive components complement active components?

Both active and passive components are indispensable in a circuit. They depend on each other and complement each other. Without active components, the circuit cannot be activated or perform a specific work. Without passive components, the circuit cannot be controlled and adjusted, nor can it achieve a stable operating state. Such a relationship between the two is like the relationship between the “dynamic” and the “static” of a circuit.

What Are the Differences Between Active and Passive Components?

For example, in an audio amplifier circuit, the power supply and amplifier are the active components, and the load and resistance are the passive components. The power supply provides energy, the amplifier amplifies the signal, and controls and limits it through load and resistance, and finally realizes the amplification and regulation of the audio signal. In signal processing, inductors filter out high-frequency noise and protect sensitive active components from interference. Transformers, on the other hand, enable efficient power transfer between different parts of the circuit, allowing active components to operate within their optimal voltage range.

Comparing the Energy Requirements of Active and Passive Elements

Active components need an external power source to function. They consume energy during operation. Passive components do not need external power and generally do not consume energy, except for minor resistive losses. This difference impacts the design and efficiency of electronic circuits.

Active components, such as transistors and integrated circuits, rely on external power to operate. This power requirement means that active components consume energy during their operation. The amount of energy consumed depends on the specific component and its application. For instance, a power amplifier consumes more energy than a simple transistor switch.

Passive components, in contrast, do not need external power to function. They operate solely based on the electrical energy present in the circuit. Resistors, capacitors, and inductors do not consume significant energy, except for minor resistive losses in resistors. This low energy requirement makes passive components more efficient in certain applications.

What Are the Differences Between Active and Passive Components?

The difference in energy requirements between active and passive components impacts the overall efficiency of electronic circuits. Designers must carefully balance the use of active and passive components to achieve optimal performance and energy efficiency. For example, using passive filters instead of active ones can save energy in low-power applications.

Active and Passive Component Images and Symbols

Recognizing symbols are essential for reading and designing circuit diagrams. They provide a visual representation of the components and their functions, helping designers understand the overall structure and operation of the circuit. Recognizing these symbols is a fundamental skill for anyone involved in electronics. Here is a detailed images and symbols listing of common active and passive components.

Above all is the introduction to passive and active components, hope it is useful for every engineers. Best Technology is a professional PCB and PCBA manufacturer in Asia. We have our own factory in China and Vetnam. Welcome to contact us if you have any questions about components and PCB assembly.

What Are the Benefits of DFM in PCB Manufacturing?
Monday, March 18th, 2024

In the PCB manufacturing, we always heard a word – DFM, do you know what is DFM? And how does it affect the manufacturing? Herein, Best Team would like to explain the DFM and its benefits for you.

What is DFM?

DFM stands for Design for Manufacturing. It is an engineering approach focused on designing products in a way that optimizes their manufacturability, testability, and reliability right from the beginning stages of product development.

The goal of DFM is to simplify the manufacturing process, reduce production costs, and improve the overall quality of the final product. This involves considering manufacturing constraints and capabilities early in the design phase to minimize complexities, facilitate assembly, and enhance efficiency in production. By integrating DFM principles, manufacturers and engineers/designers can achieve cost savings, faster time to market, and higher-quality products.

What We Should Considered About Design for Manufacturing?

Design for Manufacturing (DFM) is guided by several key principles aimed at optimizing the design of products for efficient and cost-effective manufacturing processes. Here are five fundamental principles and considerations must know of DFM:

  1. Design

We all know the more complex the design, the greater the risk during the manufacturing. Therefore, keep the design as simple as possible while meeting the functional requirements of the product. Simplifying the design including reduce the number of parts, assembly steps, and manufacturing processes involved, which in turn lowers production costs and minimizes the risk of errors or defects.

  • Standardization

In the PCB industry, there is an IPC standard to standardized all the elements design in PCB, this involved the line width, line spacing, solder mask thickness, text height and so forth. By using standardized parts and processes, manufacturers can take advantage of economies of scale, reduce lead times, smooth the manufacturing process and simplify supply chain management. Standardization also ensures the interchangeability, repair, and maintenance of products.

  • Design for Assembly (DFA)

If you are trying to mount some components to keep and enhance the performance of product, then DFA is must to take into account. Arrange components on the PCB layout in a way can minimize signal interference, reduces trace lengths, and simplifies assembly. Placing components strategically can improve signal integrity, reduce electromagnetic interference (EMI), and facilitate automated assembly processes.

  • Material

Select materials and manufacturing processes that are readily available, cost-effective, and well-suited to the intended application. Consider factors such as material properties, availability, recyclability, and environmental impact when making material choices. Designing for materials involves optimizing designs to minimize material waste and maximize efficiency in material usage.

  • Testability and Debugging

Design PCBs with features that facilitate testing, troubleshooting, and debugging during manufacturing and assembly. Include test points, debug headers, and built-in self-test (BIST) circuitry to simplify testing and diagnostics. Design PCBs with clear labeling, documentation, and accessibility to aid in maintenance and repair.

What Are the Benefits of DFM Analyzing?

The mainly benefits of using DFM is save cost. You know, when creating a new project, we need put much money and time in designing and prototyping. DFM helps identify potential manufacturing issues early in the design phase, allowing for cost-effective modifications before production starts. By optimizing designs for manufacturability, companies can avoid expensive rework and reduce overall production costs. Statistically, we can save around 170 thousand dollars one year by adopting DFM analyzing (human cost, trail-production cost and repair cost). In addition, DFM offers numerous benefits including:

  • Reduce potential quality defects
  • Facilitate production process improvement
  • Decrease trial production cycles
  • Quick time to market
  • Enhanced product quality and stability
  • Mitigate risks associated with personnel changes

How to Find a Manufacturer with DFM Service?

Finding a reliable DFM manufacturer is essential for ensuring the success of your product development. Best Technology engaging in PCB manufacturing for more than 17 years, and we have many experts that can help to solve and provide PCB solution for you. Meanwhile, we have professional DFM system that can help to quickly diagnose the design exception such as components missing, trace layout, open/short circuit. With our expertise and advanced tools, we ensure that your PCB designs are optimized for efficient manufacturing, resulting in high-quality products that meet your specifications and exceed expectations. Trust Best Technology to be your partner in achieving excellence in PCB manufacturing.

What Is the Role of Electronic Parts on the Circuit Boards?
Tuesday, December 19th, 2023

A circuit board is an independent part of modern electronic devices, equipped with various components that play different roles and functions on the board such as connecting, signal transmission, power distribution, and signal conversion. Theoretically speaking, electronic components are the fundamental units in the devices, and printed circuit board (PCB) serves as a carrier for mounting components, connecting them to completing the functions of electronic systems. Here, we will introduce some common circuit board components and their functions.

(A_PCB_with_components)

What Are Electronic Components?

Electronic components are fundamental building blocks used in the construction of electronic circuits and systems. These components manipulate electrical signals to perform specific functions in electronic devices. Based on their purpose and functionality, electronic components can be categorized into two major types: passive components and active components.

Passive electronic components mainly include resistors, capacitors, inductors, power filters, and so on. They do not have active operational functions such as amplification or signal control. Instead, passive components can only consume or store electrical energy. In electronic systems, their main roles include signal transmission, distribution, filtering, isolation, and other similar functions.

Active electronic components, on the other hand, include transistors, field-effect transistors (FETs), integrated circuits (ICs). Unlike passive components, active components have the ability to actively amplify, control, and manipulate signals related to current, voltage, frequency, and more. They play a crucial role in electronic systems, enabling active operations and functionalities.

(Components_on_a_pcb)

What Is the Functionality of Common Components on PCB?

On an assembled circuit board (PCBA), we can see various of components on its surface. Different components play its unique role and have different function. Here we will introduce the function of common components.

  • Resistor

A resistor is a component used to restrict the flow of electric current. Its purpose is to control the magnitude of current by adjusting its resistance value, ensuring appropriate current adjustment within the circuit.

  • Capacitor

The capacitor has the ability to store charge and release it when needed. Its function is to smooth power supply voltage, stabilize current, and in some cases, perform signal filtering to accomplish signal conditioning. Resistors and capacitors are two common types of electronic components.

  • Diode

Diode is a type of component with unidirectional conductivity. The uses of diode enable to allow current to flow in one direction while blocking reverse current. It is commonly used in power supplies, rectifiers, and other circuits.

  • Transistor

A transistor functions in amplification and switching in a printed circuit board. Its role is to amplify electronic signals, control the flow of current, and it is widely used in circuits such as amplifiers and logic gates.

  • Integrated Circuit (IC)

Integrated circuit is a very important components in those small size circuits, because it can integrate multiple functional circuits onto a single chip. That means it can save space if your design has limited space, enhance system performance and reliability of devices. Integrated circuits find widespread applications in areas such as computers, communication systems, and embedded systems.

  • Inductor

The working principle of inductor is similar to a capacitor, but the different is an inductor has the ability to store and release energy while capacitor is to store and release charge. Its main function is to accomplish energy conversion and distribution in a circuit. Inductors are commonly used in circuits for filtering, power supplies, and more.

  • Variable Resistor

A variable resistor allows for the adjustment of resistance and it always used for modifying circuit characteristics by changing the resistance value. Variable resistors are commonly used in circuits for functions like volume control, light intensity adjustment and some other devices that need to adjust the resistance.

  • Light Emitting Diode (LED)

LED chips is a component that we can see everywhere need to light up. It converts electrical energy into light energy. Its function includes emitting light for indicators, illumination, and it is widely used in circuits such as display screens and indicator lights.

  • Power Module

Power module is always designed to provide the electrical energy required by a circuit. Using power to stabilize output voltage and current, protecting the circuit from external power fluctuations.

  •  Sensor

A sensor can perceive physical quantities or signals in the surrounding environment and convert them into electrical signals. Its function is to enable interaction between the circuit and the external environment. Sensors find wide applications in areas such as automatic control, the Internet of Things (IoT), and more.

(PCBA)

In summary, the various components on a circuit board have their specific roles, work in conjunction with each other, and collectively achieve the functionality and objectives of the circuit. Understanding the functions of these components allows for a better grasp of the working principles of circuit boards, providing reference and guidance for the design and maintenance of electronic products.

However, for some reasons, inspect the components before PCB assembly is the main method that ensures the reliability of a PCBA. In our next post, we will share how to make the incoming inspection for electronic components, leave your messages if you are interested in it.

What is PCB Embedded Component Process?
Wednesday, November 22nd, 2023

The resistance and capacitance buried in multi layers PCB process is a process of burying resistors and capacitors inside the PCB board. Usually, the resistors and capacitors on the PCB are directly soldered on the board through mounting technology, while the buried resistor and capacitor process is to embed the resistors and capacitors into the internal layer of the PCB board.

This kind of printed circuit board consists of a first dielectric layer, a buried resistor, a circuit layer and a second dielectric layer in order from bottom to top. Among them, the part of the buried resistor without a circuit layer on the buried resistor is covered with a polymer isolation layer, and the surface of the polymer isolation layer is roughened, the surface roughness Rz is bigger than 0.01 ÎŒm, and the thickness of the polymer isolation layer at the corners is at least 0.1 ÎŒm.

The printed circuit board of the utility model covers a layer of polymer isolation layer on the surface of the buried resistor, thereby protecting the buried resistor from being attacked and corroded by chemical chemicals during subsequent wet processes such as browning and super-coarseness, and improving the efficiency of manufacturing buried resistors. Resistor plate process capabilities further promote the application of buried resistive plates to inner layer buried resistors.

The advantages of the buried resistor and buried capacitor process include:

1. Space saving:

Since the resistors and capacitors are embedded directly into the internal layers of the board, space on the PCB board can be saved, making the entire circuit board more compact.

2. Reduce circuit noise:

Embedding resistors and capacitors into the internal layers of the board can reduce the electromagnetic interference and noise of the circuit and improve the stability and anti-interference capabilities of the circuit.

3. Improve signal integrity:

The buried resistance and buried capacitance process can reduce the transmission delay and reflection loss of circuit signals and improve the integrity and reliability of signal transmission.

4. Reduce the thickness of the PCB:

However, the buried resistor and buried capacitor process is relatively complicated in terms of manufacturing and repair, because the resistors and capacitors cannot be directly observed and replaced. In addition, the buried resistance and buried capacitance process is usually used in high-end electronic products, and the cost is relatively high.

When it comes to high-density circuit design, PCB buried resistance and buried capacitance technology has become a very useful technology. In traditional PCB layout, resistors and capacitors are usually soldered on the PCB surface in the form of patches. However, this layout method causes the PCB board to take up more space and may cause noise and interference on the surface.

The buried resistance and buried capacitance process solves the above problems by embedding resistors and capacitors directly into the internal layer of the PCB board.

The following are the detailed steps of the PCB buried resistor and buried capacitor process:

1. Make the inner layer:

When making a PCB board, in addition to the conventional layers (such as outer layer and inner layer), it is also necessary to make a separate inner layer specifically for buried resistance and buried capacitance. These internal layers will contain areas for buried resistors and capacitors. The inner layers are usually made using the same techniques as regular PCB manufacturing, such as electroplating, etching, etc.

2. Resistor/capacitor footprint:

Resistors and capacitors are packaged in a special package in the buried resistor and capacitor process so that they can be embedded into the internal layer of the PCB. These packages are usually thinned to accommodate the thickness of the PCB board and have good thermal conductivity.

3. Buried resistor/capacitor:

In the process of making the inner layer, the buried resistor and capacitor process is completed by embedding resistors and capacitors into the inner layer of the PCB board. This can be achieved through a variety of methods, such as using special pressing techniques to embed resistors and capacitors between inner layers of material, or using laser technology to etch holes in the inner layer material and then fill them with resistors and capacitors.

4. Connection layer:

After completing the inner layer of the buried resistor and buried capacitor, connect it to other regular layers (such as the outer layer). This can be achieved through conventional PCB manufacturing techniques such as lamination, drilling, etc.

In general, the buried resistance and buried capacitance process is a highly integrated technology that embeds resistors and capacitors in the internal layer of the PCB board. It can save space, reduce noise, improve signal integrity, and make PCB boards thinner and lighter. However, due to the complexity, the buried resistor and buried capacitor process is usually used in high-end electronic products with higher performance requirements.

Do You Know How Does the ENEPIG Working for Wire Bonding Circuit Boards?
Friday, November 10th, 2023

The electronics industry has continuously pursued smaller and faster electronic products with increased functionality. To meet these demands, the electronic packaging industry has focused on developing more advanced packaging methods, aiming to increase the density of components on a circuit board while integrating multiple functions into a densely package.

The increasing density of packaging and interconnection has driven the progression of assembly methods from through-hole technology (THT) to surface-mount technology (SMT). Additionally, the use of wire bonding to connect chips to substrates has become more prevalent. The adoption of smaller interconnect pitches and chip-scale packaging (CSP) has further increased component density, while multi-chip modules (MCM) and system-in-package (SiP) have enabled the integration of more functions on a single package.

This post describes the key factors affecting the reliability of interconnections, with a particular focus on the specific properties of surface-treated wire bonding, emphasizing the selection of wire bonding surface treatments.

Selection of Surface Treatment for Wire Bonding

While electroless nickel gold provides excellent performance for wire bonding, it has three main drawbacks that hinder its application in cutting-edge technologies:

1. The relatively high demand for gold layer thickness leads to lengthy process costs.

2. Thick gold layers are prone to the formation of weak tin-gold intermetallic compounds (IMC), reducing the reliability of solder joints. To enhance solder joint reliability, alternative surface treatments may be used, but this increases additional process costs.

3. The electroplating process requires the use of electroplating lines, limiting the design freedom and wiring density of the packaging substrate.

The limitations posed by electroplated nickel-gold provide an opportunity for the adoption of chemical plating. The techniques of chemical plating include Electroless Nickel Immersion Gold (ENIG), Electroless Nickel Electroless Gold (ENEG), and Electroless Nickel Palladium Immersion Gold (ENEPIG).

Among these three options, ENIG is generally unproblematic due to its lack of high reliability in gold wire bonding properties (although it has been used in some low-end consumer products). On the other hand, ENEG shares the high production cost and presents complex challenges in terms of the manufacturing process, similar to electroplated nickel-gold.

ENEPIG was initially introduced in the late 1990s, its market acceptance was delayed until around the year 2000 due to fluctuations in palladium metal prices (which were inflated to unreasonable levels around 2000). However, ENEPIG can meet the requirements of many new packaging applications, providing reliable performance and conform to lead-free/ROHS requirements, with a recent strong surge in market demand.

In addition to the advantages in packaging reliability, the cost of ENEPIG is another benefit. With the recent rise in gold prices surpassing US$800/oz, it becomes challenging to control costs for electronic products requiring thick gold plating. The price of palladium (US$300/oz), relative to gold, is less than half, making palladium a cost-effective alternative with surface-related advantages.

Comparison of Surface Treatments

Up to now, for printed circuit boards accommodating fine-pitch QFP/BGA components, there are primarily four lead-free surface treatments:

Immersion Tin (IT)

Immersion Silver (IAg)

Organic Solderability Preservatives (OSP)

Electroless Nickel Immersion Gold (ENIG)

The table below compares these four surface treatments with ENEPIG. Among these surface treatments, none can simultaneously meet all the requirements of lead-free assembly processes, especially when considering multiple reflow experiences, pre-assembly shelf life, and gold wire bonding experiences. In contrast, ENEPIG offers good shelf life, solder joint reliability, gold wire bonding capability, and can serve as a touch button surface, providing surface-related advantages. Moreover, in the final gold replacement deposition reaction, the chemical palladium layer in ENEPIG works to protect the nickel layer, avoiding excessive corrosion during gold replacement.

(Table 1 – Comparison_of_Different_Surface_Treatment_Performances)

What Are Advantages of ENEPIG?

ENEPIG has several crucial advantages, demonstrating reliable solderability and gold wire bonding concurrently. The key benefits are outlined as follows:

  • Prevention of “Black Nickel Problem” – The absence of gold replacement attacking nickel on the surface prevents interfacial corrosion.
  • The chemical palladium layer acts as a barrier, preventing copper from diffusing to the surface, ensuring satisfactory solderability.
  • Palladium layer enable to completely dissolves in the solder, preventing the exposure of a high-phosphorus layer at the alloy interface. After the dissolution of the chemical palladium layer, the chemical nickel layer is revealed, forming a satisfactory nickel-tin alloy.
  • Capability to Withstand Multiple Lead-Free Reflow Cycles
  • Excellent Gold Wire Bonding Properties

These advantages make ENEPIG a preferred choice in various applications, ensuring reliable performance in both soldering and wire bonding processes while offering cost efficiency. As a one-stop PCB supplier in Asia, Best Technology possesses advanced technology and high-tech manufacturing equipment that can meet the “multi-variety, small volume, high quality, strong capability, short delivery” requirements. Welcome to contact us if you are going to find a reliable circuit board manufacturer.

How Can I Reduce and Optimize the Cost of My PCB in A Best Way? – Series 2
Saturday, October 28th, 2023

At our latest blog, may the readers have understood the factors that will affect the PCB price, or maybe one of your have put it into practice that get a price lower than your budget. However, people are always not satisfied by the existing situation. If this is bother you as well, keep reading since this time we are going to sharing some useful tips that enable to optimize your PCB price until to the best.

  • Reduce board complexity

It can be said that try to simplest your design/layout and make it easy to fabricate is the simplest way to reduce your PCB cost. The more complex and irregular the forms, the higher the cost. Just remember: for every circuit board, no need to maintain a fancy diagram to demonstrate its excellence, perform functionality correctly is enough.

  • Design it in right size and thickness

Design your board in right size doesn’t means make it smaller as possible. You must know, if your design is complex and layouts are density, that means maker need to spend more time to assemble them. Highly compact sizes are always expensive, don’t skimp when it counts. Otherwise, more money will be spent to afford what you saved.

And in theory, the more layers and thickness the board, the more cost that manufacturer spend. Numerous layers in the PCB will have an influence for holes and diameters. It is recommended that if thinner thickness is enough, then just do it. 

  • Shapes, holes and rings should be regularly

Normally, keep the PCB as square or rectangular shapes is cheaper than irregular shapes like pentagon.  And large holes and rings enable to smooth the production run and easy to create. For smaller holes and rings means the driller must be smaller and delicate control.

  • Consider volume and choose manufacturer

In our last blog, we emphasize manufacturers will set a minimum order quantity (MOQ), it is common in this industry. So, consider your volume and check multiple quantities before ordering can help to recognize which one is the most cost-effective.

During the evaluation period, talk to your suppliers as soon as possible, knowing more about the material specifications, technical and PCB tolerances. A wrong choice will lead to much time waste and some unnecessary cost. This is we call “trial and error cost”. Try to make all things are clear and correct before production.

  • Pick the best vias

There are totally three types of vias in PCB: though-hole, blind, buried. The through hole can be passed through the whole board, while blind vias is created from top or bottom side to the middle of the board without through to bottom or top side. Buried vias, just as its names, it is buried inside the boards and we can’t see it by naked eyes.

Obviously, through hole is cost performance than other two vias, try to use more instead of blind or buried vias enable to decrease your cost. In additionally, blind and buried vias are always necessary in HDI PCB and RF board, otherwise, you don’t usually use them.

  • Make sure all SMT components on the one side

Trying to make all the surface mounted (SMT) components on the one side of circuit board if possible. In this way, assembler can finish the SMT process in one-time, so that can save much manufacturing time and cost. But if the components are distributed on both sides, it is needed to assemble two times, that is top side first – bottom side second (or sometimes bottom first).

  • Select easily replaceable component parts

It is assumed that one of part on your circuit becomes obsolete, then you must search for replaceable part or update your design if you would like to continuedly use this board. As an extensive experienced PCB manufacturer, we strongly recommend that select components that has standard dimension, so that it is easy to match alternative one.

In addition, visit some manufacturer’s website carefully to see if any components are marked as “obsolete” or “not recommended for new designs” before finishing your design. This enables to avoid secondary update.

  • Follow manufacturer’s PCB fabricate standards

Understand and follow manufacturer’s fabricate standards can keep your unit PCB price in a relative lower cost. When designing a new project, please make sure to following below tips.

  1. Use standard stack-up with standard materials.
  2. Design 2-4 layers PCB if possible.
  3. Keep your minimum line width and spacing within the standard spacing.
  4. Avoid adding extra special requirements as much as possible.
  • Use SMT components as possible

Choose surface mounted (SMT) components instead of through hole (THT) component whenever possible. SMT and THT are almost treated as separated manufacturing processes. Hence, if all the THT components can be replaced by mounted parts, the THT process will be eliminated completely. It is not only decreasing the manufacturing cost, but also reducing delivery time. Of course, it is not always possible, but it’s worth trying.  

Whatever decisions you make, the best solution is to consult and discuss with your suppliers. They be always to give you the best one that can save your money and meet your requirements as well. Meanwhile, if you don’t believe the suppliers, you are welcome to reach us. We promise that we can give you a most favorable price and high-quality product.

What Factors Affect the PCB Board Price? How to Keep the Best Price? – Series 1
Saturday, October 28th, 2023

For each development engineer or purchaser, how to keep the cost within the budget is a most irksome and irritating assignment while the PCB has the good quality and enable to perform desired function. They need to understand the computation rule and calculate the developing cost. So, it is worth to knowing the factors that affect the printed circuit board price, and it is a must learn course for every engineers. Herein, Best Technology is going to dissect the factors affect the cost of PCB, let’s move on!

What affects the cost of a PCB?

Drives the cost of PCBs are numerous, we can see from the PCB itself, for example, circuit board substrate materials, the external factors such as the manufacturing difficulties, the whole order quantities and some other special requirements that from designers.

Here, we listing some basic parameter factors which drives the whole cost of a PCB.

  • PCB substrate material

The substrate of PCB board refers to the material used in the non-conductor part of the circuit board, mainly FR4, glass fiber, epoxy resin, polyimide, copper, aluminum and so on. In the PCB manufacturing, glass fiber is widely used in the manufacture of double-sided circuit board and multi-layer board, while epoxy resin and polyimide are used in the manufacture of high-density multi-layer board. Among them, copper substrate is most expensive material. No matter what kind of materials, all of them shall be calculated according to the real-time international price.

  • PCB size (panel and single pcs)

PCB size will determine the price of PCBs, this is for sure. Generally speaking, with a same number of PCB layers, the smaller the PCB size, the cheaper the cost. Because during calculating cost, vendors will consider the utilization rate of raw materials. Make sure the highest utilization, the cost for both purchaser and vender will be best. The raw material of PCBs is commonly 1200mm*1200mm, or 1220mm for special specifications, when the utilization achieves 90% or above, this is the best.

So, how to improve the utilization of raw materials? Normally, manufacturers will optimize the working files (WF) from single size to panel size, and then material will be cut according to the panel files. But if the panel size is not suitable, then there will be a lot of waste edges of raw material in the cutting process, and generally this will be added into your PCB price. So that the unit PCB price will be more expensive. In another word, if you PCB size is well-suited, then it is good for PCB manufacturer and yourself. And at this time, the utilization will be the highest and your PCB cost is the cheapest as well.

  • Line width/spacing

To a certain extent, as long as you are following the PCB design rules, the PCB price will not too high. However, if your design is complex and the line width is extreme thin, then the price will increase since it is difficult to control during manufacturing.

  • PCB layers

According to the IPC standard, PCBs can be classified to single-layer PCB, double sided PCB and multilayer PCB. For layer count over than 2 layers, we called it as Multilayer PCBs, such as 4 layers PCB, 6 layers PCB. For FR4 PCB, we can make up to 32layers.

Due to the manufacturing process and some unpredictable assembling cycles, the more the layers, the more expensive it is. (The price of single side PCB is the similar to double sided PCBs.)

  • Solder mask ink color

In the past, it is no doubt that you will spend more if you want every color expect green. But now things are changeable. Most colors are available at no or very little extra cost, which usually only occurs for unique requests such as matte tones.

  • PCB copper foil thickness

The weight of copper foil depends on the successful utilization of the material. Thicker copper is more expensive and comes with additional manufacturing difficulties and expenses. You may also have to fill the holes with copper foil to connect layers. In addition, heavier copper means you need to spend more cost in shipping. Let’s take a simple example, for aluminum core PCB and copper core PCB, in the same volume and quantities, copper core PCB stands out for expensive shipping cost since it has thicker copper and heavier weight.

  • PCB surface treatment

Surface treatment is a method that using for protecting the surface from corrosion and improve the solderability. Usually, in consideration of environmental friendliness, vendors can use a couple of gold or silver to achieve further safety for use in some applications.

The commonly used surface treatment methods include OSP, IMMERSION SILVER, ENIG, ENEPIG and HASL (LF). Among them, the price is ENEPIG>ENIG>IMMERSION SILVER>OSP>HASL. You can calculate the PCB board price according to the surface treatment method and gold thickness.

  • Quantity and lead time

When developing a new project, almost of companies would like to make prototypes first and ask for a sample quotation. However, some PCB manufacturers will set the minimum order quantity, the smaller the quantity, the higher cost the PCB board. Please make sure to check the price for different amount before placing an official order.

Meanwhile, the delivery time request also will affect the whole price in a certain. And certainly, the price of quick turn order and expedited service will higher than normal order.

  • Other special requirements (impedance, IPC standard)

To ensure the stable transmission of circuit board signals and improve the quality of signal transmission, designers and engineers will ask for impedance control for the traces. This can be seen as special requirements, so it will add a few extra prices. And the required IPC Criteria is a factor as well. Normally, if customer does not have other request, we will default use IPC class II. III level will more expensive.

Above all are the mainly factors that affect the price composition for a printed circuit board. When evaluating your PCB cost, making them in your consideration is best.

PCB and PCBA supplier that can save cost for you – Best Technology

When you are seeking for a reliable PCB and PCBA supplier, I would like to recommend Best Technology to you. Best Tech offers one-stop service including raw material purchasing, PCB making, components searching, assembly, box building and package out of warehouse. What we can provide is not limited to PCB, but also metal core PCB, ceramic PCB, flexible PCB, rigid flex PCB, special PCB like HDI PCB, heavy copper PCB, extra thin PCB and so on. During the 17 years, the Best Technology company has served include medical industry, consumer electronics, new energy, automotive electronics, aerospace, military and others.

Could it be said that you are searching for a PCB supplier that can provide favorable price that lower than market? If this is true, please go ahead and reach us today, let’s talk about more PCB information right now and start our business trip together. We promise, when you decide to take the first step, and we’ll take the remaining 99 steps.

Understanding Counterbore and Countersunk Holes in PCB Design
Saturday, July 8th, 2023

When we talking about the holes in PCBs (Printed Circuit Boards), may somebody always curious about two special holes: Counterbore hole and Countersunk hole. They are easy to be confused and easy to misunderstanding if you are a layman of PCB. Today, we will introduce the differences between counterbore and countersunk for details, let’s keep reading!

What is a Counterbore Hole?

A counterbore hole is a cylindrical recess on a PCB that has a larger diameter at the top surface and a smaller diameter at the bottom. The purpose of a counterbore hole is to create space for a screw head or a bolt’s flange, allowing it to sit flush with or slightly below the PCB surface. The larger diameter at the top accommodates the head or flange, while the smaller diameter ensures that the fastener’s shaft or body fits snugly.

What is a Countersunk Hole?

On the other hand, a countersunk hole is a conical recess on a PCB that allows the head of a screw or bolt to sit flush with the PCB surface. The shape of a countersunk hole matches the profile of the fastener’s head, creating a seamless and level surface when the screw or bolt is fully inserted. Countersunk holes typically have an angled side, often 82 or 90 degrees, which determines the shape and size of the fastener head that will fit into the recess.

Counterbore VS Countersunk: Geometry

While both counterbore and countersunk holes serve the purpose of accommodating fasteners, their main difference lies in their geometry and the types of fasteners they accommodate.

Counterbore holes have a cylindrical recess with two different diameters, while countersunk holes have a conical recess with a single diameter.

Counterbore holes create a stepped or raised region on the PCB surface, whereas countersunk holes result in a flush or recessed surface.

Counterbore VS Countersunk: Fastener Types

Counterbore holes are primarily used for fasteners with a head or flange, such as bolts or screws that require a solid mounting surface.

Countersunk holes are designed for fasteners with a conical head, such as flathead screws or countersunk bolts, to achieve a flush surface.

Counterbore VS Countersunk: Drill angles

Different sizes and drilling angles of drill bits are offered for producing countersinks, depending on the intended use. These angles can include 120°, 110°, 100°, 90°, 82°, and 60°. However, the most frequently employed drilling angles for countersinking are 82° and 90°. For optimal outcomes, it is essential to align the countersink angle with the tapered angle on the underside of the fastener head. On the other hand, counterbore holes feature parallel sides and do not necessitate tapering.

Counterbore VS Countersunk: Applications

The choice between counterbore and countersunk holes depends on the specific requirements of the PCB design and the components being used.

Counterbore holes find applications in situations where a secure and flush fastening of components or mounting plates is necessary. They are commonly used to fasten connectors, brackets, or PCBs to an enclosure or chassis.

Countersunk holes are often employed when aesthetic considerations are important, as they provide a sleek and level surface. They are frequently used for mounting PCBs to surfaces where a flush finish is desired, such as in consumer electronics or decorative applications.

Counterbore and countersunk holes are important features in PCB design, enabling efficient component mounting and secure fastening. Understanding the differences between these two types of holes allows designers to select the appropriate option based on the specific requirements of their circuit board applications. Whether it’s ensuring a secure connection or achieving a visually pleasing finish, the choice between counterbore and countersunk holes plays a crucial role in the overall functionality and aesthetics of a PCB assembly.

5 Tips Tell You How to Solder BGA Better in PCBA
Monday, May 29th, 2023

BGA (Ball Grid Array) soldering is a widely used method in the electronics manufacturing industry for mounting integrated circuits onto printed circuit boards (PCBs). This method provides a more compact and reliable connection compared to traditional through-hole or surface mount technology (SMT). However, the complexity of BGA soldering poses various obstacles during the manufacturing process. Herein, we will explore the challenges faced in BGA soldering and discuss effective strategies to address them.

What is BGA Soldering?

BGA soldering is a technique that involves the attachment of integrated circuit packages to a PCB using an array of solder balls. These solder balls are typically made of lead-based or lead-free alloys, depending on environmental regulations and specific requirements. The BGA package consists of a substrate, which acts as a carrier for the integrated circuit, and the solder balls that form the electrical and mechanical connections between the package and the PCB.

(BGA_balls)

The Importance of BGA Soldering in Electronics Manufacturing

BGA soldering plays a critical role in the manufacturing of various electronic devices such as computers, smartphones, and gaming consoles. The increased demand for smaller and more powerful electronics has driven the adoption of BGA packages. Their compact size and high pin density make them suitable for advanced applications where space is limited.

Challenges Faced in BGA Soldering

  • Component Alignment and Placement

One of the primary challenges in BGA soldering is ensuring accurate component alignment and placement on the PCB. The small size of the solder balls and the dense layout of the BGA package make it difficult to achieve precise positioning. Misalignment during the assembly process can result in solder bridges, open connections, or mechanical stress on the package.

To address this challenge, manufacturers employ advanced technologies such as Automated Optical Inspection (AOI) and X-ray Inspection. AOI systems use cameras and image processing algorithms to verify the correct alignment and placement of BGA components. X-ray inspection, on the other hand, allows manufacturers to see beneath the surface of the PCB and detect any misalignment or defects that may not be visible to the naked eye.

(Alignment)
  • Solder Paste Application

Another significant challenge in BGA soldering is achieving precise and consistent solder paste application. Solder paste, a mixture of solder alloy and flux, is applied to the PCB pads before placing the BGA package. Inadequate or excessive solder paste can lead to solder defects such as insufficient solder joints, solder voids, or solder bridging.

To overcome this challenge, careful attention must be given to stencil design and aperture selection. Stencils with appropriate thickness and properly sized apertures ensure accurate solder paste deposition. Additionally, manufacturers can employ Solder Paste Inspection (SPI) systems to verify the quality and consistency of the solder paste applied. The solder paste that Best Technology uses is SAC305 solder paste, which has good printability and excellent stability.

(SAC305_Solder_paste)
  • Temperature Profiling

Temperature profiling, or we can say the thermal management, it is crucial in BGA soldering to ensure proper reflow of the solder paste. The reflow process involves subjecting the PCB to a carefully controlled temperature profile, allowing the solder paste to melt, form a reliable joint, and solidify. Inadequate temperature profiling can lead to insufficient solder wetting, incomplete reflow, or thermal damage to components.

Manufacturers must optimize the reflow oven setup and calibration to achieve the correct temperature profile. Thermal profiling techniques, such as the use of thermocouples and data loggers, help monitor and control the temperature during the reflow process.

  • Reflow Process

The reflow process itself presents challenges in BGA soldering. The soak zone, ramp rates, and peak temperature must be carefully controlled to prevent thermal stress on the components and ensure proper solder reflow. Inadequate temperature control or improper ramp rates can result in solder defects such as tombstoning, component warpage, or voids in the solder joints.

Manufacturers need to consider the specific requirements of the BGA package and follow recommended reflow profiles provided by component suppliers. Proper cooling after reflow is also essential to prevent thermal shock and ensure the stability of the solder joints.

(BGA_reflow)
  • Inspection and Quality Control

Inspection and quality control are critical aspects of BGA soldering to ensure the reliability and performance of the solder joints. Automated Optical Inspection (AOI) systems and X-ray inspection are commonly used to detect defects such as misalignment, insufficient solder wetting, solder bridging, or voids in the solder joints.

(AOI)

In addition to visual inspection techniques, some manufacturers may perform cross-section analysis, where a sample solder joint is cut and examined under a microscope. This analysis provides valuable information about the quality of the solder joint, such as solder wetting, void formation, or the presence of intermetallic compounds.

In a word, BGA soldering presents unique challenges in electronics manufacturing, primarily related to various factors. By addressing these challenges effectively, manufacturers can ensure the reliability and performance of BGA solder joints, contributing to the production of high-quality electronic devices. Best Technology has rich experience in PCBA assembly and we mounted thousands PCBs for our customers, whatever it is simple design or complex design, all the products are assemble perfect and work well in customer side. Please feel free to contact us for any questions about PCBA.