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Industrial Motherboard Design, Industrial PCB Case Sharing
Monday, June 24th, 2024

Best technology engaging in the PCB manufacturing and PCB design for more than 17 years. With a strong R&D team, we can provide customers with fast and valued PCB design solutions. Here is one of our industrial motherboard design & industrial PCB case sharing for your reference. If you want to get your own industrial PCB design, welcome to contact us.

A mITX architecture industrial control motherboard

[1] Intel Xeon E3, Core™ i7/i5, Celeron G3900E processors

[2]:2x DDR4 SODIMM 2133 MHz (up to 32 GByte)

[3]:4x SATA Gen 3.0

[4]:1x PCIe x16 (Gen 3)

[5]:2x USB 3.0 (Internal) + 1x USB 3.0 (Client) + 2x USB 3.0 (Rear I/O) + 2x USB 2.0 (Rear I/O) +

2x USB 2.0 (Front Header) + 1x USB 2.0 (mPCIe)

Industrial PCB Design Considerations

  • Control the length of the circuit: Minimize the length of the circuit, especially the key signal lines, to reduce signal attenuation and delay.
  • Avoid sharp angles and right angles: Right angles and sharp angles should be avoided when wiring, and rounded or 45 degree angles should be used as far as possible to reduce signal reflection and impedance discontinuity.
  • Line width: Determine the line width according to the current size and thermal requirements to ensure the reliability and stability of the circuit.
  • Inter-layer wiring: Rational use of multi-layer PCB inter-layer wiring, such as the signal line on the inner layer, power and ground wire on the outer layer.
  • Impedance control: For high-speed signals, it is necessary to control the line impedance to ensure signal integrity, and carry out impedance matching design if necessary.
  • Avoid cross and parallel wiring: Try to avoid cross and parallel wiring of signal lines to reduce crosstalk and electromagnetic interference.

Contact us if you have any questions and inquiry about industrial PCB design projects.

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Why is FR4 Material the Most Commonly Used PCB Material?
Wednesday, June 5th, 2024

FR4 material is a highly popular and widely used substrate in the PCB industry due to its exceptional mechanical strength, electrical insulation, and flame retardant properties. It has become the standard for PCB fabrication.

What is FR4 Material and Why is it Used in PCBs?

FR4 is a type of fiberglass-reinforced epoxy laminate. The term “FR4” comes from its flame-retardant properties, meeting the UL94V-0 standard. It is made from woven fiberglass cloth and epoxy resin, which together provide great strength and durability.

Electrical engineers and designers prefer FR4 because of its many benefits, such as:

  • Low cost
  • High dielectric strength
  • Excellent strength-to-weight ratio
  • Moisture resistance
  • Temperature endurance
  • Good electric loss characteristics
  • Flame retardance and self-extinguishing capabilities
  • Mechanical robustness
  • Insulating properties

FR4 is also suitable for marine PCBs because it absorbs very little water. In a standard FR4 PCB, a layer of FR4 is placed between two thin layers of laminated copper.

FR4 material pcb

What are the Key Performances of FR4 Material?

FR4 material, also recognized as flame retardant 4, is a composite of glass fabric and epoxy resin, predominantly utilized as a foundational material for printed circuit boards. Familiarity with the specifications of FR4 is crucial for selecting the appropriate substrate for PCB manufacturing. Key specifications include:

1. The thickness of FR4 sheet is usually 0.2 mm to 3.2 mm, and other special thickness also available.

2. The specific gravity of FR4 material is about 1.85g/cm3, which means that it is heavier than water.

3. Coefficient of thermal expansion of FR4 is about 1.0×10^-5cm/cm/℃, which means that its length or width will expand slightly when the temperature changes.

4. The thermal decomposition temperature of FR4 materials is usually between 280C and 320C, which makes it able to withstand high temperature applications.

5. FR4 material has a dielectric constant around 4.0-4.8, which makes it an ideal material for circuit board manufacturing.

6. FR4 has good arc resistance, which means that in the case of high voltage, it can effectively prevent arc discharge.

7. FR4 material good hydrolysis resistance and can maintain good performance even in a humid environment.

RF FR4 PCB

What are the Types of PCB Materials in the Industry?

PCB materials can be broadly categorized based on their composition and intended application. Nowadays, the commonly used are including FR4, polyimide (PI), Metal material (copper or aluminum), ceramic substrate like Al2O3, AlN, Si3N4, and so on. Different materials have its unique functions and well-suited in specific environment. Here we introduce their properties and suited applications simply.

FR4 (Fiberglass Epoxy Laminate)

At present, almost of PCB you seen in the market or electronics used the FR4 material. It widely used because of its superb equilibrium of mechanical strength, electrical insulation, and cost-efficiency. Actually, according to the different reinforcement materials, the circuit board is mainly classified into the following types:

1) FR-4

2) FR-1, FR-2, etc.

3) CEM series: Composite substrate

FR-4 used frequently because of its high fire resistance rating.

High Tg FR4

Though normal FR4 material has good electrical insulation, it is not an ideal option for high frequency circuit board. And then, high Tg FR4 stands out by using an advanced technology. “Tg” refers to glass transition temperature, the juncture at which the material transitions from a rigid, glassy state to a pliable, rubbery state. High Tg FR4 boasts a Tg of 170°C or higher.

Polyimide (PI)

Polyimide materials are renowned for their excellent flexibility, superior thermal stability and chemical resistance. It is always used as raw material of flex circuits, rigid flex circuit boards or membrane switches. Due to the good chemistry properties, they can endure temperatures up to 260°C and are highly flexible, making them ideal for those small and limited PCB designs.

polyimide pcb

Metal base material

Metal materials always used in metal core PCBs (MCPCB), usually used aluminum core or copper core. The metal base has great thermal conductivity to enhance the thermal management of the device, buy using metal core, the device can dissipate heat away from the critical component such as LED chips, ICs, BGAs, to remain the reliability and performance of the PCB.

metal core pcb

Ceramic substrate

Ceramic PCB substrate offers excellent thermal conductivity and stability than that metal core PCBs, making them suitable for high-power and high-frequency applications. But due to the high cost and complex manufacturing, the ceramic PCB is much expensive than metal core PCB, therefore, they are always be used in high-end applications, such as the military, defense, aerospace and some special fields where requires excellent thermal management.

ceramic pcb

Understanding these materials enable to help engineers and designers in selecting the most appropriate substrate for their projects, ensuring optimal performance and cost-efficiency. Best Technology provides a comprehensive array of PCB materials, guaranteeing high-quality solutions for all your electronic needs.

What are the Applications of FR4 PCB Material in Various Industries?

FR4 material is versatile and finds applications in numerous industries, including:

  • Consumer Electronics like smartphones, laptops, and other personal electronic devices.
  • Applied in vehicle electronics for infotainment systems, engine control units, and more.
  • Industrial Equipment such as control systems, power supplies, and industrial automation.
  • Essential for telecommunications, network devices, routers, and communication infrastructure.
  • Medical instrumentation and diagnostic equipment.
  • Aerospace and defense in avionics, radar systems, and defense electronics.

This is all of this sharing, thanks for your reading. Welcome to contact us if you have other questions about FR4 or other raw materials of PCB. Best Technology engaging in the PCB manufacturing about 18 years, we are one of the leading PCB manufacturers in China. And we have such confidence to provide with you the best PCB and PCBA fast solution for your projects.

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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.

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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.

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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.

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What You Know About Counterbores in PCB Design and Manufacturing
Friday, August 18th, 2023

In the world of design and manufacturing, precision is paramount. Every detail, down to the placement of a single component, can impact the performance and appearance of a product. This is where the concept of counterbores comes into play, a technique employed in various industries to create recessed areas for components or fasteners.

But firstly, what is counterbore?  Today we will show you the definition and applications of the countersink in a PCB design. 

Definition and Applications:

A counterbore is a cylindrical, flat-bottomed hole that is strategically cut into a material to accommodate specific components or fasteners. It is commonly used in various industries, including woodworking, metalworking, and mechanical engineering. The purpose of a counterbore is to create a recessed area where a component, such as a bolt head, nut, or other hardware, can sit flush with or below the surface of the material. This technique ensures a smooth appearance, prevents interference with other components, and provides mechanical stability.

Counterbores in PCB Design and Manufacturing

In the realm of printed circuit boards (PCBs), counterbores play a crucial role in achieving efficient and functional designs. PCBs are essential components in electronic devices, and their design requires careful consideration of component placement, connectivity, and mechanical stability. Counterbores in PCBs serve several important functions:

  1. Component Alignment and Clearance:  Certain components on a PCB, such as connectors, switches, or specialized modules, require precise alignment and clearance for optimal functionality. A counterbore can be introduced to create a recessed area that accommodates these components, ensuring proper alignment with neighboring components and minimizing the risk of interference.
  • Flush Mounting: To maintain a sleek and compact design, some components need to be mounted flush with the surface of the PCB. A counterbore creates a flat-bottomed recess that allows the component to sit at the same level as the PCB surface, contributing to an aesthetically pleasing and functional layout.
(Counterbore_hole_in_heavy_copper_PCB)
  • Mechanical Support: Components that are susceptible to mechanical stress or impact may benefit from additional support. By incorporating a counterbore, the PCB design can provide a more secure location for these components, reducing the risk of damage.
  • Heat Dissipation Enhancement: In applications where certain components generate significant heat, such as power amplifiers or processors, heat sinks are often employed to dissipate the heat. A counterbore can facilitate proper alignment and contact between the heat sink and the component, optimizing heat transfer and overall thermal performance.
(Detail_counterbore_hole)

The production of counterbores in PCBs involves specialized manufacturing techniques. BEST Technology as a professional PCB manufacturer, we will use precision drilling and routing equipment to create accurately sized and positioned counterbores.

If you want to know more about the counterbores, welcome to follow our post or contact us.

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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.

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5 PCB Testing details to make your PCB no more quality issues
Monday, April 24th, 2023

As we all know, it is very important to get a well-functional PCB from the PCB manufacturers.  A well functional PCB means that the electricity testing has been performed well at the PCB manufacturer end. However, you may have found some PCB you purchased are with some electricity issues like short & open circuits, or some visual issues like solder pad missing., etc.

Do you know how this issue come while the PCB testing process?

According to the feedback come from the customers, here we summarized some improper ways during the PCB Electricity testing process which may lead to the PCB fail to the test.

Here are some major points for your reference:

  • Incorrect direction when placing PCB board on testing worktop, the force on probes will cause indentation on boards.
  • PCB manufacturers don’t regularly maintain their testing jig, causing some malfunctions on testing jig can’t be found in time. Take the counter for example, if we do not find the counter’s fixing screw loose in time, it will cause the counter to fail to read the caliper scale. Of course, it also could be the counter is dysfunctional sometimes.
  • PCB manufacturers don’t regularly check/change the testing probes. Dirt on the testing probe cause testing results is inaccurate.
  • PCB testing operator don’t distinguish functional board from NG board due to unclear placement area.

So, if the circuit boards testing work under above improper way, do you know what effects will be on your products?

Base on some lessons learned from our customers, you may get following influences caused by improper way of the PCB testing.

Increase your quality issues

The low testing accuracy will make the functional PCB mixing together with the defective PCB.  If the PCB testing defects can’t be found in time before PCB assembly, defective products will flow into the market, which will seriously increase the quality risk hidden on the end products.

Delay your Progress

After defective PCBs are found, repairing will greatly delay the progress of the project.

Increase your overall cost

The defective PCB will cost many people and time to check and follow, this will directly to increase the overall cost of the projects.

We know deeply that poor testing will bring serious consequences for customers, so with more than 16 years experiences on Printed Circuits Board fabrication, Best Technology has rich experiences on PCB electric testing managements, and following are some of our management solutions to control our PCB testing process:

1.   We execute strictly the pre-job training 3 months in advance for the testing operator, and all the testing will be operated by the professional and experienced testers.

2. Maintain or replace the test equipment every 3 months, and use a brush to clean the tester in a regular period or replace the pin cable head to make sure there is no contaminate at the test probe.

3. Add the extra tooling hole at rails for fix purpose to make sure the placement of PCB orientation is no mistake during testing process.

4. The testing workshop must be divided clearly for the qualified board and NG board, the location to keep NG board will be marked with red line.

5. The testing process must be strictly followed with our internal PCB testing standard operating procedure.

With the help from above management solutions for the PCB E-Testing during the PCB manufacturing process, the PCB we send to customers works very well, which also make sure their products can be assembled well and deliver well in the markets. For us, more and more kindly feedback regarding the functional feedback comes from our customers, here are some good feedback from customers for your reference.

If you have any questions about PCB testing or PCB manufacturing, please feel your freely to leave your message or contact us. In our next update, we will share which test methods are used in the during the PCB Assembly.

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Differences Between Solder Mask and Solder Paste in PCB
Wednesday, December 7th, 2022

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

Part 1: What is Solder Mask?

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

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

Solder_mask

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

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

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

Part 2: What is Solder Paste?

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

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

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

Solder_paste

Part 3: The Difference Between Solder Mask and Solder Paste

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

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

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How To Do Failure Analysis In Printed Circuit Board
Saturday, October 29th, 2022

Nowadays, printed circuit board plays a more and more important role in electronic products, whether for personal use or commercial use, failure PCB can effect the usage of electronic products and cause a serious consequence. So, how to quickly detect the PCB fault problem?

Here, Best Tech summarized seven methods to locate fault PCB quickly.

  • Use testing equipment

The typical equipment including Automated Optical Inspection (AOI) equipment, X-Ray Fluoroscopy, Optical Microscopy, 1000x magnifying glass. When some failures happen and we don’t know what is the specific position, properly use of these detection devices can help us quickly locate the faulty PCB.

Scratch-on-PCB
  • Visual inspection

Visual inspection is the most common and easy method to position those defectives in printed circuit board. It can identify defects such as overlapped marks, solder joint short, signs of overheating circuit boards, and burned components.  When some problems are difficult to identify with our naked eye, magnifying glasses can help to identify some short circuits, welding bridges, open circuits, solder joints and circuit board wiring cracks, component offset, etc. 

  • Components inspection

If the printed circuit board was assembled with some electronic components, we can perform a components inspection to locate the failure. Especially when low resistance is detected between the component pins, it is best to remove the component from the PCB circuit for specialized testing. If the resistance is still low, then this component is the culprit, otherwise further investigation will be required.

  • Power on printed circuit board

Visual inspection is only suitable for checking the appearance of outer layers of the circuit board, instead of for checking the inner layer of the circuit board.  If there are no visible defects in the appearance, you can power up/on the board and perform a more detailed test to determine whether the board is working properly or not.

  • Low voltage measurement

The first thing to confirm is whether the voltage of each chip power pin is normal, and then check whether the various reference voltages are normal, and whether the working voltage of each point is normal. Since the copper trace on the circuit board has resistance, the voltage generated through different parts of the copper trace is also different.  Then you can use a voltmeter or multimeter to measure the voltage between different parts along a short. If you find that the voltage value is getting smaller and smaller, you are getting closer to find out a short circuit.

For a simple example, when a typical silicon triode is on, the BE junction voltage is around 0.7V, while the CE junction voltage is around 0.3V or less.  If the BE junction voltage of a triode is greater than 0.7V (except for special triode, such as the Darlington tube), the BE junction may be open.

  • Touch circuit board with your finger

In general, when some failure happened, some areas on the circuit board will be getting more and more heat. In this time, we can try to touch the circuit board with fingers to find out areas with heat, and it will help us to pinpoint the problem. However, be careful to use short-circuit copper trace power supply and avoid burns or electric shock.

  • Repair short/open

After identifying a short or open circuit on the PCB, the next step is to isolate the problem.  While this is easy to do on the outer surface of the board, it is a challenge for the inner layers.  Possible solutions include drilling through holes or cutting appropriate external copper traces.

This is the end of this article, if you have more better methods to locate the failure printed circuit board, warm welcome to contact us, we can analyze together.

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