Archive for the ‘FR4 PCB’ Category

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.

(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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10 Tips to Reduce the manufacturing cost of Printed Circuit Board

Thursday, March 23rd, 2023

Many times, when PCB engineer or purchaser seek for a PCB manufacturer to make circuit boards, that always think the price is too high, but don’t know where makes the price is so high and how to optimize the cost on the premise of ensuring the quality of the circuit board. Herein, we share a very useful guideline about “Ten tips to reduce the PCB manufacturing cost”, welcome to read on!

  • Substrate

Different brands of substrate have different price. For a simple example, if you require a multi-layer PCB, Tg should greater than 150o, and PP need to over 0.20mm, then use GDM will cheaper than KB or SL. But GDM is usually used for making single or double-sided PCB, it is not recommended to make multi-layer circuit board. If you need to fabricate an 8 layers of multi-layer PCB, KB Tg170 is ideal for your choice since it has good performance and relatively cost-efficient.

  • Solder mask oil

In generally, what we should consider about the solder mask (S/M) are color and brand.

For the solder mask color, the most commonly used are green, white and black, if you would like to choose other special colors such as blue, yellow, gray, the price will be a little more costly.

From the brand aspect, currently the best brand is Taiyo solder mask, because it has high viscosity, stable dielectric constant, good insulation and oxidation resistance properties, but it is more expensive than others. Other brands of solder mask oil will be relatively cheap, but the quality is not particularly stable and can’t be guaranteed. So if the circuit boards need to used on bulk products, we recommend to use Taiyo to get a stable quality.

  • Printing film

If it is a bulk order with simple design and trace width/space >= 5/5mil, almost manufacturers will use printing film to generate traces. But please remember: the larger the board size, the higher cost of film. (Generally speaking, Prototypes or small orders are use LDI exposure machine to generate the trace, but for mass production, manufacturer will priority choose film and then use LDI.)

  • Line width/space

The thinner traces, the higher manufacturing price. Because the line is thinner, the accuracy of the equipment and the quality of the chemical solution are required to be relatively high, and the yield will be relatively low, resulting in higher costs. Each manufacturer has its capability, so choose a suitable supplier is most important, view Best’s website to check our capability.

  • Drill holes

The smaller the hole, the higher the price, the diameter of less than 0.3mm will increase the price. The more holes there are, the higher the price will be. Other special holes will also increase the cost, such as half holes, blind holes, PTH holes larger than 6.0mm, etc. Because the hole is small, only one board can be drilled at a time when drilling the hole on PCB material, which is low efficiency and the possibility of drilling a broken drill bitter is also large, resulting in higher cost.

  • Finished copper thickness

Finished copper thickness ≥2oz, and hole copper >25μm board will increase the cost. Because the price of copper itself is relatively expensive, the thicker the copper, the higher the price, coupled with the cost of additional electric copper, leads to the overall price rise.

  • Finished board thickness

There is little difference in the price of PCB with board thickness of 1.2mm and 1.6mm, but if the board thickness is 2.0mm or even thicker, its cost will increase correspondingly. The thicker the board, the more sheets of fiberglass, so the cost will increase accordingly.

  • Outline

If there are more slots, and the slots are less than 1.0mm, the cost will increase. This is because the gong groove of the board is more shaped, resulting in the processing time is elongated. In addition, if the width of the groove is small, processing can not be too fast, easy to break the milling cutter, so the processing efficiency is low, the natural production cost increases.

  • Surface treatment

Our common surface treatment processes are: OSP(antioxidant), lead HASL, lead-free HASL (environmental protection), gold plating, immersion gold, ENEPIG and some combination processes. The price of the above process is more expensive in turns, that is, OSP (antioxidant) < lead HASL < lead free HASL < gold plating < immersion gold < ENEPIG.

  • Tooling fee and testing fee

Tooling fee: in generally most of manufacturers use milling cutter to punch outline if this is a prototype order or small order. But if bulk order, it is needed to use a tooling jig, so there is a tooling fee need to pay.

Testing fee: flying probe tester is usually for small order, mass production need to use testing jig, and there is a different testing fee for both.

Above elements can affect the cost of making a board, you can try to follow those guidelines if you have a limited budget. Or if you want to know a exactly cost, please send RFQ to Best Technology, our sales will give you a best price.

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Why Consider Even-Number Multi-Layer PCBs For Your Project?

Tuesday, March 7th, 2023

With the great demands about high-tech electronic equipment, although the single sided PCB or double-sided printed circuit boards have their advantages, multi-layer designs are more beneficial for some applications, that’s why the more and more popular and wide usage of multi-layer PCBs.

(Multilayer_PCB)

Currently in the market and electronic industry, almost of the multi-layer PCB have an even number of layers such as 8, 10 or 12 layers, why designers didn’t consider an odd-number layers? Today let’s explore the reasons together.

  • Higher cost spent

Normally the standard layers of a multi-layer PCB in the industry are even-numbers, and as the manufacturing technology becomes more and more mature, the cost of fabricating a multi-layer PCB is relative competitive.

But if you want to produce odd-numbers PCB, may the odd-number layers save the cost of material for one layer but the processing cost increase significantly to an even-numbers. Because the core structure requirement for odd layered PCB increases the production cost greatly. However, an even layered PCB can save these costs and reduce the overall manufacturing cost, so why not consider the even number layers?

  • Long lead time

Long delivery time is unescapable because of the immature fabricating technology. In particular with the odd-layer, the stack up will be unbalance. For example, if it’s an odd layered circuitry, due to the standard symmetrical requirement, the layers will be separated to 2 layers in a one side and another side is 3 layers, so one of the copper layers will be etched away and the odd layered PCB may create uneven weight during the copper plating stage and result in irregular plating issues. This non-standard, odd-layered stack requires an extra core process for layer bonding and adds to the manufacturing time and cost. So, it’s always recommended to use an even number of layers in the PCB stack-up.

  • Potential quality issue

Quality is very important and crucial for end-application, and the best reason of why not design an odd-number multi-layer PCB is the odd-number layers PCB is very easy to get twist due to the unbalance copper layers. When the PCB is cooled after the multi-layer circuit bonding process, the different lamination tension between the core structure and the foil structure can cause the PCB to bend when cooled. As the board thickness increases, the risk of bending becomes greater for composite PCBs with two different structures.  The key to eliminate circuit board bending is to use balanced layering.  Although PCBs with a certain degree of bending meet the specification requirements, subsequent processing efficiency will be reduced, resulting in increased costs. Because assembly requires special equipment and technology, the accuracy of component placement is reduced, so the quality will be damaged.

In addition, the twist of an even-number layers PCB can be controlled below 0.7% (IPC 600 standard), but odd layers unable to reach to this quality standard. What’s more, when the warpage of a circuit board greater than 0.7% will seriously affect the operation of Surface Mounted Technology (SMT) process and the reliability of the whole product. Therefore, the designers do not design odd layer generally, even if the odd layer enables to achieve the function, will be designed into false even layer, that is, 5 layers designed into 6 layers, 7 layers designed into 8 layers of board.

Anyway, more layers it is, more complex & difficult the manufacturing will be, and more expensive the cost will be, and the lead time of multi-layer PCB also is different from normal one. So you must choose a right supplier who can provide One-stop service include designing, evaluating, manufacturing or even repairing. Best Technology is an expert in the production of multi-layer PCBs for many companies around the world for over 16 years. Contact us right now and send us inquiries, we are so confident that we can be one of your most reliable suppliers in China.

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Do You Know What a Metal Core PCB Is?

Saturday, February 25th, 2023

Metal Core Printed Circuit Board (short for MCPCB) is a technology developed to overcome the thermal limitations of the FR4 Printed Circuit Board. Different with traditional FR4 PCB, the PCB uses FR4 material as base core, while the base material of a metal core PCB is aluminum or copper. So compared with FR4 PCB, Metal Core is a better choice if your boards need to perform in high temperature environment.

What is metal core PCB?

A Metal Core PCB (MCPCB), also known as a thermal PCB or metal backed PCB, is a type of PCB that a metal material as its base for the heating dissipation part of the board. The thick metal is covering one side or double side of the PCB. The purpose of the core of a MCPCB is to redirect heat away from critical board components (such as LED or IC chips), and to less crucial areas such as the metal heatsink backing or metallic core. Base metals in the MCPCB are used as an alternative material to FR4 boards.

(Metal_core_PCB)

Same as FR4 PCB, the metal core PCB can be divided into Single layer MCPCB, Double layers MCPCB and Multi-layer MCPCB.

  • Single layer MCPCB

A single layer MCPCB is consist of a metal base (usually aluminum or copper alloy), thermal conductivity/dielectric layer and a copper trace layer, you can check below stack up for more details. Due to it only has one layer copper trace, sometimes we called it as one-layer MCPCB or single sided MCPCB.

(Stack_up_of_single_layer_MCPCB)

The single sided MCPCB can be used with surface mount and chip & wire components, and provides much lower thermal resistance than FR4 PCB. What’s more, the metal core provides lower cost than ceramic substrates, and allows much larger areas than ceramic substrates.

Meanwhile, superior heat dissipation and good durability of Aluminum of metal core PCB can greatly eliminate heat sinks or other some voluminous hardware for engineers or designers.

  • Double layer MCPCB

Double layers MCPCB (2L MCPCB) has two copper layers on one side of PCB, and metal core as a base core on the bottom side of whole MCPCB, so the components only can be populated on the top side, below is a structure of double layer MCPCB.

(Stack_up_of_double_layers_metal_core_PCB)

From the stack up of double layers MCPCB, we can see it consists of a single layer MCPCB and a double sided FR4 PCB, so it needs an additional pressing process to laminate the thermal conductivity and FR4 PCB. Compared with normal FR4, this structure needs more technology and experience on laminating of two layers together with metal core.

There are two layers copper trace on the surface of MCPCB, can we call it as double sided MCPCB like single layer MCPCB?

The answer is NO, because they have different structure and perform different properties. In our next post, we will show you the differences between double sided MCPCB and 2 layers MCPCB.

  • Multi-layer MCPCB

Same as FR4 PCB, for those copper traces more than 2 layers, we named them Multi-layer MCPCB. Its structure is same as FR4 PCB, but more complex to fabricate. Below is a typical stack up of a 4 layers MCPCB:

(Stack_up_of_4L_MCPCB)

Contrast with single layer or double layers MCPCB, multi-layer MCPCB can populate more components and achieve better performance in electronical performance.

Why Choose Metal core PCB?

Metal core PCB offers a great list of advantages when apply in a high-power application, below we listing some benefits of it:

  • Excellent heat dissipation
  • Lower thermal expansion than FR4 PCB
  • Dimensional stability than polyimide FPC
  • Great durability
  • Long lifetime
  • High utilization rate of space due to the heating can be transferred quickly
  • High strength and lightweight than FR4 PCB
  • Cost-effective

Where can we use Metal core PCB?

Metal core PCB can be used in high-power filed where requires fast cooling, good heat dissipation characteristics, the following popular applications may give you a guideline:

  • LED lighting
  • Power suppliers
  • Power conversion system
  • Automotive electronics
  • Telecom industrial
  • Photovoltaics
  • Semiconductors

With more than 16 years manufacturing experience, Best Technology is one of MCPCB supply leaders in Asia with good metal core PCB capability, we are so confident that we can provide you high quality, fast delivery and excellent one-stop service. Warm welcome to contact us if you have inquiries.

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How to choose surface finish on Printed Circuit Board?

Saturday, December 17th, 2022

When finish the PCB design, we should choose a suitable surface finish to protect traces from corrosion. Nowadays, the most popular surface treatments for PCB manufacturer to use are HASL/LF HASL, OSP and ENIG.

Different surface treatment has its unique functionality and the cost also is different. This article we will show you the pros and cons of the three surface finishing which use while the PCB manufacturing process.

HASL Surface Finish

HASL (Hot Air Solder Level) can be known as tin-lead HASL and lead-free HASL, it was the mainstream surface treatment technology in the 1980s, but with the increased of “small and high density” demands in PCB, there are less and less circuit boards use the HASL technology because it will cause the defective products due to the solder point are easy to leave on the board surface during SMT process. In view of this situation, some PCB board manufacturers or designers prefer use OSP or immersion gold to ensure the good quality products as well as smooth production process.

  • Tin-lead HASL

Advantages:

1) Economical and widely available.

2) Excellent solderability.

3)Better mechanical strength & lustrousness than lead-free HSAL.

Disadvantages: it is harmful to environment and violates RoHS compliance.

  • Lead-free HASL

Advantages: low cost, good solder performance and environmental.

Disadvantages: mechanical strength & lustrousness are not good than lead HASL.

In additional, due to the poor surface flatness of HASL circuit boards, neither leaded nor lead-free HASL is not suitable for soldering fine-pitch components or plated through-holes, because it will cause the short circuits and poor welding during the assembly process.

(LF_HASL)

OSP

OSP (Organic Solderability Preservatives) also named as pre flux, the working principle is to generate a layer of organic film chemically on the copper surface to protect the surface from oxidation or vulcanization in the room environment. Meanwhile, OSP also can increase the oxidation resistance, heat shock resistance and moisture resistance of a PCB. 

OSP is equivalent to an anti-oxidation treatment, the protective thin film can be easily removed by the flux quickly under the high soldering temperature, then it makes the exposed copper surface immediately combined with the molten solder in a very short time to become a solid solder spot.

At present, the usage of OSP surface finishing process has increased significantly because it is appropriated for both low and high-end products. If your application has no surface connection functional requirements or storage life limitations, the OSP process is the most desirable surface treatment process.

(OSP_surface_treatment)

Advantage:

1)With all the advantages of bare copper soldering, expired (more than 3 months) boards can also be resurfaced, but one time is better.

2)Good for fine-pitch, BGA and smaller components.

3)Low cost and easy to rework.

4)Simple process and easy to ensure quality.

Disadvantage:

1)OSP is easily affected by acid and humidity, so must be packed with vacuum.

2)Need to do surface treatment again if storage time more than 3 months.

3)It should be used within 24 hours after unpacking.

4)OSP is an insulating layer, so the test point must be printed with solder paste to remove the original OSP layer for electrical testing.

ENIG

ENIG (Electroless Nickel/Immersion Gold) is one of a chemical nickel gold deposition method, the working principle is to generate a layer of coating by chemical REDOX reaction to get a thicker gold layer. Currently, ENIG is mainly used in the surface of the circuit board with connection functional requirements and long storage life.

Advantage:

1)Can be stored long time as well as no oxidation.

2)Good flatness surface and suitable for small solder point components.

3)Good solderability.

4)Can be used as the base material for COB wire bonding.

Disadvantage:

1)High cost than other two surface treatments.

2)Easy to exist black-pad issue during production process.

(ENIG)

As we can know from above information, each PCB surface treatment has its own merit and demerit, you can choose the one according to the effect you want to reach, as well as your cost. 

If you don’t know which is best for you, you can send inquiry to us, our professional engineering team and PCB sales will choose the suitable one for you. Welcome to contact us if you have any other questions.

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What is RF PCB board?

Tuesday, November 23rd, 2021

You may have ever heard of RF PCB, but do you know What it is and What are the characteristics of these kinds PCB?

Today let us make a simple introduction for it.

RF PCB, means radio frequency PCB. People also called these PCB High frequency PCB, it is for the PCB with a higher electromagnetic frequency, and it is used on the products field with high frequency. (Frequency greater than 300MHZ or wavelength less than 1 meter) and microwave (frequency greater than 3GHZ or wavelength less than 0.1 meter). It is made by microwave substrate with common PCB manufacturing process or with some special way to make.

High-frequency boards have very high requirements for various physical properties, accuracy, and technical parameters, and are often used in communication systems, automobile anti-collision systems, satellite systems, radio systems and other fields.

How can we know which PCB materials are suitable for making the RF boards?

When evaluating the high-frequency characteristics of a substrate material, the key to its investigation is the change in its DF value (Dissipation Factor).

For substrate materials with high-speed and high-frequency characteristics, in terms of changing characteristics at high frequencies, there are two distinct types of general substrate materials: one is that with the change of frequency, its (DF) value changes very little. There is another type that is similar to the general substrate material in the range of change, but its own (DF) value is lower.

The common epoxy resin-glass fiber cloth-based materials (FR4), the DK value at the frequency of 1MHz is 4.7 and the change of the DK value at the frequency of 1GHz is 4.19. Above 1GHz, the change trend of its DK value is gentle. The change trend is that as the frequency increases, it becomes smaller (but the change is not large). For example, at 10GHz, the DK value of FR-4 is generally 4.15. The substrate material with high-speed and high-frequency characteristics changes in frequency. When the DK value changes slightly, the DK value keeps changing in the range of 0.02 when the frequency changes from 1MHz to 1GHz. Its DK value tends to decrease slightly under different frequency conditions from low to high.

On the other hand, the thermal expansion coefficient of the high-frequency circuit board substrate and the copper foil must be the same. If they are inconsistent, it will cause the copper foil to separate during the cold and hot changes. Secondly, in a humid environment, the water absorption rate must be low, and high water absorption rate will cause dielectric constant and dielectric loss when wet. In general, the heat resistance, chemical resistance, impact resistance, and peel resistance of the high-frequency sheet must be good.

The following are several commonly used high-frequency and high-speed PCB boards we have summarized:

Rogers: RO4003, RO3003, RO4350, RO5880, etc.

TUC: Tuc862, 872SLK, 883, 933, etc.

Panasonic: Megtron4, Megtron6, etc.

Isola: FR408HR, IS620, IS680, etc.

Nelco: N4000-13, N4000-13EPSI, etc.

Other materials like Arlon, Teflon, Taconic are also good for the manufacturing of RF PCB boards.

If you have any question for RF pcb, welcome to send your request and question to discuss more.

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A Brief introduction for different layers on Multilayer PCB

Friday, October 29th, 2021

When it comes to multilayer PCB, we know the multilayer PCB are consisted by many different layers. Do you know what’s the purpose for these layers?

Here I would like to give you a brief introduction for the functions of each layer on a Multilayer PCB design.

Mechanical layer: There may be one or several mechanical layers in a PCB depending on the design. There should be at least one mechanical layer as it shows the physical dimensions of the board. Generally, it used GM1, GM2 to name the file on the Gerber.

Solder paste layer: This is a material applied onto the PCB layers where components are mounted, mostly through soldering. It helps with the bonding of the solder with the component pin and improves the solder flow. PCB Assembly supplier will make stencil according to the solder paste layer on the Gerber.

Generally, it used GPS, GBS to name the file on the Gerber.

Solder mask layer: This layer is a mask or a protective coating applied onto the board to prevent damage and contamination. It is typically green in color; however, you can also choose other colors such as blue, black, white depending upon your requirements. Generally, it used GBS, GTS to name the file on the Gerber.

Ground planes and power planes: These are layers for copper, the ground and the power planes are connected to an onboard voltage point. Generally, it used GND, PWR to name the file on the Gerber.

Split planes: This is a modified version of power and ground planes; they are split in a manner that they can be connected to multiple voltage points or potentials.

Keep out layer: This layer is crucial as it defines the working boundary and keeps it separate from the outer mechanical layer. Generally, it used GKO to name the file on the Gerber.

Silkscreen layer: This is typically the text displayed on the boards through which you can identify components with their names. It is typically white in color when solder mask color is green, black, blue and red. But you can also choose other colors such depending upon your requirements. Generally it used GTO, GBO to name the file on the Gerber.

Routing layer: These layers help to interconnect the components. They can also be present on the top and bottom layers of the board.

Drilling Layer: This is the layer to show the drilling information of the PCB. Usually, it names DRL on the Gerber.

Once we understand the purpose of each layer for PCB, then understanding the construction of PCB becomes easy, no matter how complicated the board structure.

With over 15 years of PCB manufacturing experience, BEST Technology can meet different requests from customers no matter it is prototype or high-volume PCB.

Send us your request, let us to make the high-quality printed circuit boards for you.

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Why most of PCB boards are green?

Tuesday, August 24th, 2021

You may have found such a situation, most of the PCB boards are with green colors, while other colors are relatively rare to see, do you know why?

As we know that the Printed Circuits Board consists of Solder Mask Layer, Silk screen layer, solder PAD, Copper traces, surface finishing and other parts, etc.

Among them, the solder mask refers to the part of the PCB that is covered by oil. Since most PCB boards use green oil, the part of the green oil that can be seen on the board surface is the solder mask, which play an important role during the reflow soldering process.  

green solder mask

Then why are most of the PCB boards green? The main reasons are as follows:

  1. Green is less irritating to the eyes. We all know that green is good for the eyes and can resists fatigue. So when the PCB board with green solder mask, relative production and maintenance personnel are not prone to eye fatigue when staring at the PCB board for a long time, and it is less harmful to the eyes.

2. Cost for Green oil is lower. Since green is the mainstream in the production process, the purchase of natural green oil will be larger, and the purchase cost of green solder mask will be lower than other colors. At the same time, using the same color oil in mass production can also reduce the replacement cost.

  • When the board works on the SMT soldering process,  it needs to go through the process from Tinning, post soldering and final AOI inspection. These processes all need to be optically positioned and calibrated. The green background color is better for the recognition of the instrument.
PCBA AOI testing

Okay, now, do you understand why most of PCB boards are with green colors?

Though we know green is the most common one, but other colors such as red, yellow, blue, purple, black or some other colors are okay for us to make.

solder mask colors

If you have PCB board with a special color want to make, please contact us and we will try best effort to meet your request.

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What kind of test for Coil Printed Circuit Board?

Wednesday, August 11th, 2021

In year 2019, one of our US customers asked us, Marina can Best Technology make a Coil PCB (Printed Circuit Board) with FR4 material? Yes, of course, we can make different kinds of PCB for our customer, included for the Coils PCB, which currently is widely used for wireless charging and antenna products. Please see the following Coils board from Best Technology.

The manufacturing process is same as other PCB manufacturing process, and just make sure the etching process and pay attention for the etching tolerance of the coils trace. And when coils PCB board finished, do you know what kind of test need to do to check the functional of Coils boards?

Today I would like to share how Best Technology test Coil PCB board. Everyone knows that we check the quality of PCB board with Flying probe tester, as the production efficiency is extremely low and the inductance and capacitance cannot be accurately measured. In this way, we need to use LCR meter to make verify the inductance and capacitance. See the LCT meter as following.

Best Technology chooses the digital meter LCR Meter to test the impedance characteristics of the coil. From the LCR tester you know see two numbers, one for inductance and another for resistance.

After test each coils printed circuit board, we will make record at our paper to make sure every measurement data will meet for customer requirement.

Currently, LCR Meter only provides a single-channel test function, and can only test the impedance characteristics of a set of coils at a time. But this is the effective test method for Coil printed Circuit Board. But we believe we will buy more LCR meters to let the test coil board become quicker.

If you have any comments on the testing for Coil printed circuit board, you are welcome to send us query and we are happy to discuss with you. You can visit www.bestpcbs.com to know more about us. Thank you

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The way to add the mouse bite on the PCB Panel #Bestpcb

Saturday, July 31st, 2021

#Bestpcb #Best PCB

Maybe you’ve ever been recommended by your PCB manufacturer to add a mouse bite on the PCB edge?

But, what’s mouse bites?  Is it something about the Rat?

Of course not, it is kind of connection way for PCB Panel.

As you know, usually the Printed Circuits Boards are manufactured on a standard sized panel, and sometime, the panel will with sharp edges, and those sharp edges are often referred to as “mouse bites” and they are left over after depanelization.

mouse bite PCB depanelization Best Technology

Mouse Bites usually presented as row of tiny holes on the board edge, just like the half holes around a stamp, which to connect and allow those small boards in an array.

mouse bite stamp holes on the PCB edge

Here is the picture for you to see how the mouse bites presented on the Gerber drawing and what it is when it is finished.

Partial Effect drawing after Penalization: (the way of connecting bridge is used in the middle, this way can reduce the residue of burr in minimize)

Partial Effect drawing pcb panel
PCB panel mouse bite

Some People also called mouse bites as perforated breakaway tabs, it is designed for a better the purpose of the mouse bites is for a better grasp when mounted.

Here is the design rules if you need to add the mouse bites on your PCB panel.

  1. The distance between each single board need to arranged as 1.2mm and 1.6mm.
  • The distance between each holes need to be 0.2mm, the distance between holes center should be 0.75mm.
  • Need to add two rows, the mouse bites extend to 1/3 of the board, if there is a some circuits on the board edge, you will need to avoid it.
  • After adding mouse bites, the shapes of the two sides of the hole are connected, which is convenient for the production of gongs after work.

Here are some of our PCB with mouse bites for your reference.

mouse bite PCB Best Technology
PCB with mouse bit

If you want to add mouse bites on your PCB board, you are welcome to send us your request and we will help you make it on your PCB Panel.

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