A high-speed circuit handles signals that switch quickly or operate at high frequencies, typically above 50 MHz, though some advanced systems may go into the GHz range. Best Technology is a one-stop PCB manufacturer that covers pcb design, pcb layout, pcb diagram, DFM, SI, PI analysis, PCB manufacturing and so on. In the following, you can see a high speed pcb design solution for industrial switch that we cooperated with our customer.
32 x 400GE industrial switch
[1]: Marvell-400G chip
[2]: 200A maximum current
[3]: Single pair differential line 56G optical network
[4]: 24 layers high power PCB
Whatās the Best Material for High-Speed PCB Design?
Choosing the right material is vital for maintaining signal integrity and achieving optimal performance. The material impacts the boardās dielectric constant (Dk), loss tangent, and overall signal quality. Common materials include:
FR4: Widely used but not ideal for very high frequencies due to higher loss tangent.
Rogers (RO4000 series): Preferred for high-speed designs thanks to its low dielectric constant and loss tangent.
Teflon: Excellent for high-frequency applications but more expensive and harder to process.
Selecting the appropriate material ensures the PCB can handle high-speed signals without compromising performance.
For the PCB design service, we can make sure the one-time success to save much time and money for customers. Our goal is to work with customers together and win more market with our clients. Just feel free to contact our technical team if you have similiar designs.
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
[5]ļ¼2x 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.
Copper Clad Laminate as a base material of FR4 PCB, serving as a key part in the building of printed circuit board. Understanding what Copper Clad Laminate is, its benefits, types, and manufacturing process is essential for anyone who involved in the electronics industry. This article aims to provide a comprehensive overview of copper clad laminate material, and hope everyone in the PCB industry be interested in it.
What is copper clad laminate?
Copper Clad Laminate, short for CCL, is an electronic glass fiber cloth or other reinforcing material dipped in resin, one or both sides covered with copper foil and made of a plate-like material, referred to as copper clad plate. It also called āCoreā when used in the multi-layer PCB designs. Through the different process like etch, drill or copper plating, we can generate different patterns, layouts onto the surface of the CCL, and then form a circuit board that we saw in the electronics.
CCLs provide the necessary support and electrical insulation in an electronic device, while also facilitating the pathways for electrical currents through the copper foil. So, in another word, the performance, long-term reliability and stability of the PCB depend on the CCL to a large extent.
What are the types of copper clad laminates?
Generally speaking, copper clad laminate can be divided into two main types according to its mechanical properties, they are ā rigid copper clad laminate and flexible copper clad laminate. Here we listing the detailed types of CCL.
Rigid copper-clad laminate
a. According to different insulation materials and structures: organic resin clad copper laminate, metal clad copper laminate, ceramic clad copper laminate.
b. According to the thickness of the plate: conventional copper-covered laminate and thin copper-covered laminate. The thickness less than 0.5mm (doesnāt include the copper foil) is called thin CCL.
c. According to the reinforcement material used: electronic glass fiber cloth base copper foil board, paper base copper foil board and composite base copper foil board.
d. According to the insulating resin used, such as epoxy resin copper-coated foil board, polyester resin copper-coated foil board and cyanate resin copper-coated foil board.
e. Special rigid copper clad plate, according to the flame-retardant grade and some special properties.
Flexible copper clad laminate
a. polyester types (flame retardant and non-flame retardant)
b. polyimide type (flame retardant, non-flame retardant)
c. Extra thin electronic glass fiber cloth copper foil laminate
Whatās the main composition of copper clad laminate?
A normal copper clad laminate mainly consists of copper foil and some auxiliary materials. These materials make the CCL conductive and be used as the core material of the circuit board. Here we would like to explain these compositions in details:
Copper foil
Copper foil is one of the main raw materials for manufacturing copper clad laminate, and it is a very pure metal material with excellent electrical conductivity. The thickness and purity requirements of the copper clad foil are very high, usually between 18-70Ī¼m, and the purity is more than 99.8%. In the manufacturing process of CCL, copper foil is used as a conductive layer to transfer current from one electronic component to another. It also has good plasticity and ductility, and can be bent, stretched and formed as needed without adversely affecting electrical conductivity. In addition, the corrosion resistance of the copper foil is also very good, which can resist the erosion of chemical substances, ensuring that the CCL can work properly in a variety of environments.
Auxiliary materials like resin and adhesive
In addition to copper foil and copper clad foil, the production of CCL also involves some other auxiliary materials, such as adhesives and reinforcing materials. Among them, the adhesive is mainly used to fix the copper foil and copper clad foil on the substrate. The selection of adhesives should take into account their adhesion and high temperature resistance to ensure that the copper foil and copper clad foil can be firmly bonded to the substrate. Reinforcement materials are mainly used to improve the mechanical strength and bending resistance of CCL. Common reinforcement materials include glass fiber cloth and polyimide film.
CCL Manufacturing Process
The manufacture of CCL is a meticulous process; therefore, it includes many accurate steps:
Prepare substrate ā the commonly used substrate is fiberglass cloth impregnated with epoxy resin, which is non-conductive material and has good insolation and mechanical properties, then cured to get the correct mechanical and thermal characteristics.
Surface treatment ā this is a surface cleaning and grinding process to achieve a clean and roughness surface of the substrate, resulting a good adhesion between the copper foil and substrate.
Copper Foil Lamination – lamination of copper foil onto the prepared substrate is done by temperature and pressure quickly and smoothly to obtain a stable bond. This is a lamination process of single layer CCL, if you want a multi-layer CCL, coating adhesive on each layer and then laminate in the press machine, then making them in a whole product.
Cutting and Trimming – the need for the dimensions drives the sheets to be cut and trimmed into a desired size.
Quality Checking: A thorough quality check follows to confirm that the CCL matches industry requirements on thickness, adhesion, and electrical properties.
Where is the Copper Clad Laminate uses?
CCL has a widely applications thus constituting a critical element for numerous electronic devices and systems, the typically are including:
Consumer electronics like cell phones, laptops, and tablets
Automotives including infotainment and engine control units
Industrial equipment like common test equipment
Telecommunications such as networking equipment and communication devices
Medical device, for example: imaging system, diagnostics
If you are looking for a company that can advance and improve your electronic circuit, then Best Technology is the right choice for you. Best Technology is a one-stop solution providers in China with extensive years of experience in high quality PCB and PCBA manufacturing. We have certificated by ISO9001, ISO13485, IATF16949 to make you no worry about the quality. Contact us right now to get your quotations!
In the design of electronic devices and systems, power distribution and heat dissipation management are key factors. Bus bar PCB, as an efficient solution, is particularly outstanding in these aspects. In this article, we would like to introduce the advantages of Bus bar PCB and its applications in different industries.
What Is A Bus Bar PCB?
At the beginning, we should know what a bus bar PCB is. The Bus bar PCB is a special and newest design that integrates the FR4 material and metal alloy into a whole product, which allows the current transfer path into the circuit board. Due to the current carry capacity and special shape, it also called busbar PCB, embedded bus bar PCB, extruded copper PCB, copper inlay PCB, copper extrusion PCB.
Bus bar circuit board provide a more compact and efficient means of current distribution than traditional wires and cables. This design improves the overall performance of the electronic system by reducing inductance, increasing current carrying capacity, and optimizing heat dissipation.
What Are the Advantages of Bus Bar PCB?
Bus bar PCB offers numerous benefits when be using the power supply applications, its main functions are:
1. Reduce the inductance
Bus bar PCBs reduce inductance by allowing current to flow between tightly spaced conductors. This layout reduces the loop area and thus the inductance value. This is particularly important for high-frequency and highspeed applications, as it reduces voltage spikes and noise, improving system stability and performance.
2. Enhanced current carrying capacity
Due to its large cross-sectional area and high-quality conductive materials, Bus bar PCB can efficiently carry large currents. This is particularly useful in applications that require a large amount of power distribution, such as power supplies, electric vehicles, and renewable energy systems. Bus bar PCBs support higher current density compared to conventional PCB wiring, which improves thermal management and reliability.
3. Improve thermal management
The Bus bar PCB effectively dissipates heat generated by key components. In high power applications, the buildup of heat can affect performance and life. The Bus bar PCB helps maintain optimal operating temperatures through efficient heat distribution, reducing the need for additional cooling mechanisms.
4. Save space and weight
The compact design of the Bus bar PCB reduces the overall size and weight of the electronic components. Its simple construction and elimination of multiple wire connectors contribute to space savings. This is particularly beneficial for applications where size and weight are critical, such as the aerospace and automotive industries.
5. Improved reliability and durability
Bus bar PCBS have superior mechanical strength and durability compared to traditional wiring systems. Its robust construction and secure connections reduce the risk of loose connections, failure due to vibration, and mechanical wear. This improves system reliability and service life for harsh environments and demanding applications.
6. Simplify assembly and maintenance
Using a Bus bar PCB simplifies the assembly process because it reduces the number of individual wires and connectors. This not only speeds up installation, but also reduces assembly errors. In addition, the Bus bar PCB provides a more orderly and accessible layout for easy troubleshooting and repair.
7. Cost effective
Although there may be a high initial cost, Bus bar PCBs can provide cost savings in the long term. Its advantages in reduced inductance, improved thermal management and enhanced reliability reduce operating and maintenance costs. In addition, Bus bar PCB reduces the need for addons, such as heat sinks or complex wiring bundles, thereby increasing overall cost effectiveness.
What Applications of Bus Bar PCB?
Due the high current carry capacity of the bus bar PCB, makes it very suitable for power supply or power management devices. Bus bar PCB can perform well in such fields. Here are some common application examples that bus bar PCB can be used for. If you are seeking for a PCB to integrate into your power supply project, then bus bar PCB is the go-to-choice.
1. Power Electronics
In power converters, inverters and high-current power supplies, Bus bar PCBS are widely used because of their ability to efficiently handle high currents and excellent thermal performance.
2. The Automobile industry
Another popular field that bus bar PCB used in is automotives, especially in electric vehicles (EVs) and hybrid electric vehicles (HEVs). In the electric cars, it can be used for battery connectivity and power distribution, contributing to weight reduction and performance improvements.
3. Renewable energy
Bus bar PCB is an environment friendly material, it is often used in solar systems, wind turbines and energy storage solutions to manage high currents and enhance reliability.
4. Industrial equipment
In industrial machinery and equipment, Busbar PCB provides powerful and efficient power distribution for motors, drives and control systems.
5. Aerospace
Bus bar PCBS are used in aerospace applications, such as avionics and power distribution systems, where size, weight and reliability are key factors.
Final Words
All in all, bus bar PCB offers significant advantages in handling high currents, improving thermal management, and providing reliable power distribution across various applications. By integrating bus bar PCBs, industries can achieve better power management, reduced system size and weight, and improved overall reliability.
Best Technology is a one-stop PCB solution provider in Asia, we offer various kinds of PCBs not only include bus bar PCB, but also Extra thin PCB, RF PCB, HDI PCB, Heavy copper PCB, Ceramic PCB, Metal Core PCB, Flex PCB and rigid flex PCB, PCBA and so more. We have more than 17 years-experience in PCB design and manufacturing, and served more than 1200 customers. Choosing Best Technology as your supplier ensures you get high quality PCBs, helping to improve the performance and competitiveness of your products. Contact us right now to customize your own PCB!
Gold plating is a common surface finish in PCB manufacturing, also known as nickel gold electroplating. It provides excellent conductivity, corrosion resistance and good durability to electronic devices. However, not all gold plating is created equal. There are two primary types of gold plating are used in PCB fabricating: hard gold plating and soft gold plating. They differ in properties, manufacturing process and applications, letās explore it today!
What are Hard Gold Plating and Soft Gold Plating?
In the manufacturing process of printed circuit boards (PCBs), we often hear the words “soft gold” and “hard gold”. They are actually describing the different metal materials used in the gold-plating process.
Hard gold usually refers to an alloy formed by electroplating process. This alloy is doped with other metal elements, such as nickel, cobalt, etc., to make it harder and more resistant to friction. Hard gold is especially suitable for places that require force and friction, such as the edge contact points of circuit boards (commonly known as “gold fingers”), because it can withstand frequent insertion and removal operations. Although the processing process of hard gold is complex, it can be doped with other metals to improve the hardness of gold, making it more suitable for making hollow jewelry or for industrial applications.
Soft gold refers to the state of pure gold or close to pure gold, because of the high purity of gold, it is relatively soft. Soft gold is mainly used for aluminum wire on COB (Chip On Board), or the contact surface of mobile phone keys, because it can maintain good electrical conductivity and weldability. The processing process of soft gold is relatively simple, does not require complex alloying process, and maintains the soft characteristics of gold, which is suitable for the production of solid jewelry or for applications requiring good electrical conductivity.
Properties and applications: hard gold plating vs soft gold plating
Hard gold plating is known for its high hardness, typically achieved by alloying gold with small amounts of nickel or cobalt. So, it has highly resistant to wear and mechanical stress. The thickness of hard gold plating is usually greater than that of soft gold plating, ranging from 30 to 50uāā or more. Best Technology can make up to 50uāā if you required. Due to the hardness of the hard gold plating, they are commonly used in edge connectors, keypads, and contact points where repeated mechanical action occurs.
The manufacturing process of soft gold plating involves a chemical process to deposit a thinner layer of pure gold onto the PCB surface. The coated pure gold without any alloying elements, resulting in a softer finished compared to the hard gold plating. Additionally, the thickness of soft gold plating is typically thinner than that of hard gold plating, usually around 1 to 3uāā. Due to the softness and conductivity properties, the soft gold plating technology is often used in applications requiring high conductivity and precision, such as wire bonding and fine-pitch components in high-frequency and high-speed circuits.
Whatās the difference between gold plating and immersion gold?
Actually, Immersion Gold is mostly called ENIG (electroless nickel immersion gold) surface treatment method. The advantage of this method is that nickel and gold can be attached to copper without electroplating process, and its surface is smoother than gold plating, which is especially important for the shrinking electronic parts and components requiring flatness.
The method of leaching gold is chemical deposition. A coating is formed by chemical redox reaction, which is generally thick. Electroplating gold is based on the principle of electrolysis, also known as electroplating. Most other metal surface treatments are electroplating. In actual product applications, 90% of the gold PCB board is dipped in gold, because the poor weldability of the electric gold-plated board is its fatal defect.
Nickel gold coating with stable color, good brightness, smooth coating and good weldability can be deposited on the surface of printed circuit by gold leaching process. It can be divided into four stages: pretreatment (degreasing, micro-etching, activation, post-leaching), nickel plating, gold leaching, post-treatment (waste gold washing, DI washing, drying). The thickness of gold leaching is 0.025-0.1um. Gold is used in the surface treatment of the circuit board because gold has strong electrical conductivity, good oxidation resistance and long service life. General applications such as keyboard board, gold finger board, etc.
Choosing between hard gold plating and soft gold plating for your PCB depends on your specific application requirements. At Best Technology, we offer expert guidance and high-quality PCB manufacturing services to help you select the best surface finish for your needs. Choose us as your trusted PCB supplier to ensure reliable and efficient solutions for all your electronic projects.
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.
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 1.0Ć10^-5cm/cm/ā, 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.
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 170Ā°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 260Ā°C and are highly flexible, making them ideal for those small and limited PCB designs.
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.
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.
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.
High-Density Interconnect (HDI) PCBs are revolutionizing the electronics industry with their advanced capabilities and compact designs. As technology continues to evolve, the demand for smaller, faster, and more efficient electronic devices has led to the widespread adoption of HDI PCBs.
What is Definition of HDI PCB?
HDI board refers to High Density Interconnect, that is, high density interconnect board, which is a relatively new technology developed by the PCB industry at the end of the 20th century.
The drilling of the traditional PCB board is affected by the drilling tool, and when the drilling aperture reaches 0.15mm, the cost is already very high, and it is difficult to improve again. The drilling of HDI board no longer relies on traditional mechanical drilling, but uses laser drilling technology. (This is why it is sometimes called a laser plate.) The hole diameter of the HDI board is generally 3-5mil (0.076-0.127mm), the line width is generally 3-4mil(0.076-0.10mm), the size of the pad can be greatly reduced, so more line distribution can be obtained within the unit area, and the high-density interconnection comes from this.
Smaller device spacing, more I/O pins and embedded passive devices Larger ASiCs and FPGAs with increasingly shorter rise times and higher frequencies all require smaller PCB feature sizes, which is driving a strong demand for HDI/ micro through-holes. The typical high density interconnector designs are including:
1+N+1
2+N+2
3+N+3
4+N+4
What are the benefits of HDI PCB?
HDI is a compact circuit board designed for small volume users. Compared with ordinary FR4 PCB, the most significant feature of HDI is the high wiring density, and the difference between the two is mainly reflected in the following three aspects.
1. HDI is smaller and lighter
HDI board is a traditional dual panel as the core board, through continuous stacking layer by layer. This kind of circuit board made by continuous layering is also called Build-up Multilayer (BUM). Compared with traditional circuit boards, HDI circuit boards have the advantages of “light, thin, short and small”.
The electrical interconnection between the HDI board is realized through the conductive through hole, buried hole and blind hole connection, its structure is different from the common multi-layer circuit board, and a large number of micro-buried blind holes are used in HDI board. HDI uses direct laser drilling, while standard PCBS usually use mechanical drilling, so the number of layers and aspect ratio tend to be reduced.
The high density of HDI board is mainly reflected in the hole, line, pad density, and layer thickness.
ā Micro-via hole
The HDI board contains the design of micro-pilot holes such as blind holes, which is mainly reflected in the micro-hole formation technology with a diameter less than 150um, and the high requirements of cost, production efficiency and hole position precision control. In the traditional multilayer circuit board, there are only through holes and no tiny buried blind holes.
ā Fine line width and line distance
Its main performance in the wire defects and wire surface roughness requirements are more and more stringent. Generally, the line width and line distance do not exceed 76.2um.
ā High pad density
The density of welded contacts is greater than 50 per square centimeter.
ā Thinning of medium thickness
It is mainly manifested in the trend of the thickness of the interlayer medium to 80um and below, and the thickness uniformity requirements are becoming more and more stringent, especially for high-density plates and packaging substrates with characteristic impedance control.
2.Ā Better electrical performance
HDI not only enables end-product designs to be miniaturized, but also to meet higher standards of electronic performance and efficiency at the same time.
The increased interconnect density of HDI allows for increased signal strength and improved reliability. In addition, the HDI board has better improvement for RF interference, electromagnetic wave interference, electrostatic discharge, heat conduction and so on. HDI also uses full digital signal process control (DSP) technology and a number of patented technologies, with a full range of load adaptability and strong short-term overload capability.
3. The HDI board has very high requirements for buried holes
It can be seen from the above that whether it is the volume of the board, or the electrical performance, HDI is better than ordinary PCB. Where the coin has two sides, the other side of HDI is as a high-end PCB manufacturing, its manufacturing threshold and process difficulty are much higher than ordinary PCB, and there are more problems to pay attention to when producing – especially the buried hole jack.
What are the basic parameters of HDI PCB?
HDI PCB has greater different with normal FR4 PCB, from the stack up, material selection, manufacturing and cost. So, it is vital to understanding the basic parameters of a high-density interconnect board before start your designing trip. The standard parameters of HDI board mainly include the following aspects:
Numbers of layers
Generally, the number of layers of HDI board is 4-20 layers, and the high-end HDI board can reach to 40-50 layers.
Line width/spacing
Due to the HDI PCB are always used in high-end applications, their line width and spacing are usually very strict, and the common requirement is that the line width/spacing is 4/4mil (0.1mm), or even smaller.
Blind hole, buried hole, bus
These are one of the characteristics of the HDI board, blind hole and buried hole can reduce the area of the circuit board, make your design more density, and the bus enable to improve the signal transmission rate of the PCB.
Board thickness
The board thickness of HDI board is usually range from 0.8 to 3.2mm, of which 1.6mm is the most common thickness.
Pad
The pad on the HDI board is generally very small, and the common pad size is 0.2mm to 0.5mm. Different factory has different capabilities, it is best to ask your supplier or manufacturer to get a manufacturing capability document.
Impedance control
For high-speed signal transmission circuits, the impedance control of the HDI board is very important, and the requirements are very strict. It is needed to tell your vendor if your HDI board will be used in high-speed devices.
Material
The main materials of HDI board are FR4, BT, PI, PET, etc. Different materials can meet different requirements.
This is the end of this sharing, contact us today to learn more about our HDI PCB solutions and how we can help you achieve your technological goals. In our next chapter, we will introduce the manufacturing process and methods of HDI boards, let me know if you are interested in it.
Have you ever seen several small holes on the rails of the PCBs or located at the board edges? They look like trails bites by mouse, do you know what they are? And whatās the function of these? This blog may make you sense about it.
What is Stamp Hole on PCB and its Purpose?
Stamp holes, also sometimes called breakaway holes or mouse bites, are small holes drilled in a row or array along the rails or edges of each circuit board within the panel. They look like the edges of a stamp, so people call it āstamp holesā.
Stamp hole is used primarily in the process of depanelized PCBs. De-paneling is the process of separating individual PCBs from a larger panel, which is a common method in PCB manufacturing to improve production efficiency and reduce costs. The larger panel makes handling and processing multiple PCBs easier during the manufacturing process. In some ways, panel also improves the utilization of the raw materials. Once the manufacturing steps are complete, the individual PCBs need to be separated for use in their corresponding devices. And these holes between the single PCBs can create a weak point along which the boards can be easily broken apart after manufacturing be completed.
Why Use Stamp Holes Expertise In PCBs?
It is possible to use stamp holes if the boards are abnormal shaped or round. The stamp hole is connected between each circuit boards, which mainly plays a supporting role and avoid PCB be scattered. Most commonly, they are used to create PCB stand-alone modules, such as Wi-Fi, Bluetooth, or core board modules, which are then used as stand-alone components placed on another board during PCB assembly.
The use of stamp holes allows for a relatively clean break along the separation line, but it may leave behind rough edges or require additional finishing steps to smooth out the remnants of the perforation points. This method of depaneling is a cost-effective solution and can be used for various types of PCBs, but it might not be suitable for very delicate circuits or when a perfectly smooth edge is required. In addition, V-cut and hollow connection strips also are the common depaneling ways for PCBs.
What are differences between Stamp Hole, V-cut and Hollow strip?
When preparing a panel for the manufacturing of multilayer PCBs, it’s essential to consider a method used to connect individual boards within the panel. As mentioned above, there are three connection methods for PCB technology, each serving different types of PCB designs and requirements. So, which one is the better or how to choose a suitable one for your project? Welcome to keep reading.
V-Cut (V-slot)
V-cut is the most common way to separate the PCBs during the circuit board manufacturing. It mainly utilizes for PCBs with straight edges or straight lines. This method involves cutting a V-shaped groove along the line where two PCBs are connected within the panel. When implemented, V-cuts leave a narrow gap (the width of the V-cut itself) between the boards. V-cut depth is an essential point during the process, make sure it has 1/3 depth on top and bottom side. The V-cut is especially suitable for standard, rectangular PCB designs, allowing for a clean and efficient separation of the boards once all other manufacturing processes have been completed.
Stamp Holes
For PCBs with unique or irregular shapes, stamp holes are often the preferred method of connection. Its process involves drilling multiple small holes in an array at the points where the individual PCBs connect within the panel. These holes create a perforated line that weakens the material enough to facilitate easy separation of the boards by applying minimal force, without compromising the integrity of the circuitry. But this way can only be used if you donāt have strict requirements for burrs on edges. And it is easy to damage the whole board if use improper approach.
Hollow Connecting Strips
Hollow connecting strips are used in scenarios where a very narrow strip of material is left to connect the boards within the panel. This method is particularly useful for PCBs utilizing half-hole (castellated holes) technology. The narrow strips maintain the alignment and integrity of the PCBs during the manufacturing process but can be easily removed or broken away to separate the individual boards. Hollow strip is less common but essential for specific designs and technologies.
Each of these connection methods has its specific applications, advantages, and considerations. The choice between V-cuts, stamp holes, and hollow connecting strips depends on the design of the PCB, the requirements of the manufacturing process, and the desired ease of separation post-manufacturing.
How to Add Stamp Holes on Your Circuit Board?
Designing stamp holes is a critical step in preparing your PCB for the depaneling process. This includes creating a series of small holes along the intended lines of separation between individual boards in a panel. Here’s a step-by-step guide to help you incorporate stamp holes into your PCB design effectively:
1. Understand the Purpose
Recognize that stamp holes are used to facilitate the manual separation of PCBs from a panel after the manufacturing process, minimizing the risk of damage to the board and its components.
2. Plan Your Layout
Placement: Decide where the stamp holes will be located on your PCB layout. They should be placed along the edges where the PCB will be separated from the panel.
Number and Spacing: The number of stamp holes and their spacing can significantly affect the ease of PCB separation. Typically, a distance of 0.5mm between holes and 1.0mm between centers of holes are used, but this may vary based on the PCB material and thickness.
3. Select the Hole Size and Quantity
The diameter of stamp holes usually ranges from 0.6 mm to 1 mm. The size may depend on your specific requirements and the capabilities of your PCB manufacturer. As for quantity, 5-8 holes in an array is good (always 2 arrays/rows), more also is available, it can be adapted based on your specific needs.
4. Arrangement of Stamp Holes
Two rows of stamp holes should be added at the edge of the PCB, extending slightly into the board. This design ensures that any burrs left on the board edge after separation will not affect the PCB’s overall dimensions. If there are traces or other critical components on the edge of the board, ensure that the stamp holes are placed to avoid damaging these elements during separation.
5. Design Using PCB Design Software
Use your PCB design software (such as Altium Designer, Eagle, or KiCad) to add the stamp holes to your design. This can usually be done by placing a series of via or pad holes along the separation lines.
Some software packages may offer tools to automate this process, allowing you to specify the number of holes, their spacing, and diameter, and then automatically place them along a line.
6. Consult with Your Manufacturer
Before finalizing your design, consult with your PCB manufacturer for any specific guidelines or requirements they have for stamp holes. This can include preferred sizes, spacing, and any additional considerations to ensure the depaneling process goes smoothly.
Provide detailed documentation of your stamp hole design to your manufacturer to avoid any confusion during the production process.
7. Review and Adjust
After adding the stamp holes to your design, review the layout to ensure that there is adequate clearance between the holes and any nearby components or traces. This is crucial to avoid damage during the separation process.
Adjust the size, spacing, and number of stamp holes as necessary to meet both your design requirements and the manufacturer’s capabilities.
In the design process, these considerations should be adjusted based on the specific PCB design and manufacturing requirements. Moreover, find a reliable PCB manufacturer to ensure these design details are accurately implemented is key to successfully fabrication.
Best Technology specializes in PCB manufacturing for more than 17 years, offering comprehensive PCB production and design services to over 200 countries worldwide. To ensure the best quality and fast delivery, we set up a strictly quality control system according to ISO9001 and equipped with advanced measured devices such as AOI, X-RAY, 2D, 3D measurement tools in our factory. We provide 24/7 hours service and commitment with a timely reply within 10 hours. We sincerely appreciate your any comments or consults, welcome to contact us at any time.
In the design of electronic products, electromagnetic compatibility (EMC) is a crucial consideration. Particularly in the design of printed circuit boards (PCBs), the rationality of EMC design directly impacts the performance and stability of the product. Among the many factors affecting EMC, one factor is especially critical, and that is the design of the ground plane. Today, letās talk about the impact of grounding on EMC.
In an electronic product, grounding is a very important element, it is directly related to EMC compliance. Especially in large equipment, the grounding of multiple systems and subsystems is involved. It can be said, a good grounding system means the half successfully of a product.
What are Ground Plane and EMC in a PCB?
The ground plane, as the reference potential in a circuit, not only carries the return path of current but also plays a role in electromagnetic shielding and noise suppression. In high-frequency circuits, the impedance and layout of the ground plane have a significant impact on signal integrity. Unreasonable ground plane design may result in signal interference, increased radiation, and decreased system stability.
EMC stands for Electromagnetic Compatibility. It refers to the ability of electronic devices and systems to operate properly in their intended electromagnetic environment without causing or experiencing interference. EMC ensures that devices can function without adversely affecting other devices nearby or being affected by electromagnetic interference from external sources. Generally, the ground planes will showing three shapes, please see as following:
Why A Grounding Must be Designed in PCB?
Grounding can be understood as an equipotential point or plane serving as the reference potential for a circuit or system, which can be a specific ground layer in a PCB or the metal chassis of a product. While many perceive the purpose of designing a ground plane primarily to prevent external electromagnetic interference (EMI), but in printed circuit board design, it serves multiple purposes beyond this.
Generally, a well-designed ground provides a common reference zero potential for all circuit units within a system, ensuring no potential difference between circuits and thus stable operation. It also protects circuits from damage, ensuring the safe functioning of electronic products. For instance, ground can provide discharge paths for transient disturbances and dissipate accumulated charges on product metal enclosures induced by static electricity, to prevent potential sparks that may cause interference internally. Additionally, choosing appropriate grounding for shielding structures can yield effective electromagnetic shielding.
Grounding design is very necessary especially for medical industry. As we know, there are many medical devices are directly connected to patients’ bodies, such as monitors. In cases where the chassis carries voltage due to poor grounding, fatal risks may arise. Furthermore, grounding reduces common-mode interference currents flowing through PCBs and prevents high-frequency EMI signals within products from reaching equivalent radiating antennas. Thus, grounding is typically a primary method for noise suppression and interference prevention.
Design Principles of Ground Plane in PCB
A well-designed grounding system should not only consider the radiation and conduction of individual PCBs but also prevent from a systemic perspective. In the design phase, failure to carefully consider the grounding system may indicate a high likelihood of EMC failure for the system. So, knowing the design principles is extremely important to make sure the successful of EMC.
Keep it short and wide
To reduce the impedance of circuits, especially in high-frequency circuits, the ground plane should be made as short and wide as possible. This helps to minimize the return path of the current, thereby reducing EMI.
Partition layout
For complex PCB designs like multilayer PCBs, it is recommended to use a partition layout to separate the ground planes of different functional modules. This helps to isolate noise interference between different modules.
Single-point ground and multipoint ground
Depending on the circuit’s operating frequency and signal characteristics, choose between single-point grounding or multipoint grounding. Single-point grounding is suitable for low-frequency circuits, while multipoint grounding is more suitable for high-frequency circuits.
Ground plane
Where possible, use a ground plane as the ground. The ground plane can provide a low-impedance return path and aid in electromagnetic shielding.
How to Optimize Your Grounding Design?
As for PCB that has already design the circuit layout, how to optimize the ground to get the maximum EMI? Here are some tips that may helpful for you.
Fill the blank areas of the PCB with ground planes to increase the ground plane’s area and reduce impedance.
Reducing the area of ground loops helps to decrease electromagnetic radiation and induced noise.
Power lines and ground planes should be placed as close as possible and run parallel to reduce the area of the current loop.
Placing decoupling capacitors between power and ground planes helps to filter out high-frequency noise.
In PCB EMC design, ground plane design is an essential step that cannot be ignored. By following the principles and optimization methods of ground plane design, the EMC and signal integrity of electronic products can be significantly improved. Therefore, in PCB design, sufficient attention and consideration must be given to ground plane design. Welcome to contact Best Technology if you want to know more about ground and EMC design.
Electronics devices and parts are existing everywhere in this big data era, and more and more engineers trying to step in the electronics design and development. As a one-stop PCB and PCBA manufacturer in China, Best Technology would like to share some basic considerations and tips during the PCB designs. Hope this can help you.
Substrate Material
Substrate is the main composition of a circuit board and it mainly used for suppler and copper foil insulation. The commonly materials are FR4 and PI. FR4 is a widely acceptable international grade for fiberglass reinforced epoxy laminated, and it always used for making rigid PCB or rigid-flex PCB. FR4 substrate has good insulation and mechanical strength, so it can be widely used in various applications. However, PI has higher heat and chemistry resistance, more suitable for high temperature and chemical corrosion environment. Ā
Circuit Layout
The layout design depends on the dimensions, performance and reliability of a circuit board, it is needed to follow your supplierās standard to make sure the fast production time and high quality.
Min line width
Please make sure your line width within your supplierās manufacturing capability, that is to say, if it is less than the minimum line width will not able to be produced. The best way is if the design conditions available, the larger the line width, the better the factory production. Generally, the line width keeps around 10mil is the best. In another word, if your line width is less than normal standard, it would be difficult for you to find a suitable supplier.
Min line spacing
Min line spacing means the distance between trace and trace. Normally, from the production aspect, the distance from line to pads should not less than min line spacing, and it would be better if it is larger, generally equal to or more than 10mil.
The spacing between circuit to outline should be control in 20mil.
Plug-in Hole
The diameter of plug-in hole should be considered by the side of components, but it is necessary that it must greater than the componentās pins, it is recommended that greater at least 0.2mm. That is to say, if the pin of components is 0.6mm, then the plug-in holes should be greater than 0.8mm. Otherwise, the plug-in components would be probably difficult to insert into PCB because of the tolerance control during the manufacturing and assembly.Ā
Min Hole Diameter
As we all know, the holes in PCB almost be used for mounting components, connect circuit and provide the electrical connection between layers. So how to design the hole also is crucial during the designing. Generally, the min hole diameter depends on the drill bitter that vendor used, always around 0.2-0.4mm. You can ask your supplier during the design evaluation.
Copper Thickness
Copper foil is a layer of metal foil on the PCB board that is used to conduct current. The thickness of copper foil is usually in oz (ounces), such as 1oz, 2oz, 3oz, etc. The thickness of the copper foil will affect the conductivity and heat dissipation performance of the PCB board.
Impendence Control
Impedance control is a key parameter in high-speed signal transmission and high-frequency circuit design. It involves board thickness, copper foil thickness, substrate dielectric constant, pad and line layout and other factors to improve the signal integrity and anti-interference ability of the PCB board.
The production process of PCBs is rather complex, involving a wide range of techniques from simple mechanical processing to sophisticated machining, so you should understand the design rules very clearly when you are trying to design a PCB board. Its applications are also diverse, from consumer electronics to industrial machinery, where PCBs are utilized.
Best Technology offers one-stop PCB solutions, we offer service from prototyping to large-scale production and assembly. With experienced engineers and service teams, we ensure successful fulfillment of your requirements. Just send us with your design files, and we will make the circuit board for you in a very short time.
