Bus Bar PCBs are a specialized type of printed circuit board (PCB) that stand out from traditional PCBs due to their integrated conductive bus bars. These bus bars are typically made of copper or aluminum and are positioned on the surface or within the PCB. They serve the purpose of connecting electronic components, devices, or connectors and transmitting electrical currents.
Key Characteristics:
Outstanding Heat Dissipation:
Bus Bar PCBs are renowned for their exceptional heat dissipation capabilities. The integrated conductive bus bars efficiently conduct and dissipate the heat generated within the circuit, making them an ideal choice for high-power applications. Whether it’s in industrial electronics, electric vehicles, or solar inverters, this characteristic ensures that electronic components stay cool, enhancing overall system reliability.
Compact Space Utilization:
Space is often a precious resource in electronic devices. Bus Bar PCBs optimize space utilization through their integrated conductive bus bars. Unlike traditional wiring systems that can be space-consuming, Bus Bar PCBs save space, reducing the overall footprint of electronic systems.
Enhanced Electrical Performance:
The integration of conductive bus bars reduces the overall resistance and inductance of the circuit, resulting in improved electrical performance. Lower resistance translates to reduced power loss, while decreased inductance facilitates faster signal propagation. This, in turn, leads to higher efficiency and improved signal integrity.
Conclusion:
Bus Bar PCBs represent a force of innovation in the field of electronics, with their exceptional heat dissipation, space-saving design, and enhanced electrical performance making them highly favored across a multitude of applications. As technology continues to advance, Bus Bar PCBs are expected to play an increasingly pivotal role in the design and manufacturing of electronic systems.
If you have any interest in Bus Bar PCBs or any related requirements, please feel free to contact us. We have been in the field of heavy copper PCB manufacturing and bus bar PCB manufacturing more than 17 years. We are committed to providing you with outstanding products and services. Let’s explore the limitless possibilities of Bus Bar PCBs together, bringing innovation and success to your projects!
We know the precision control and performance of a product are paramount, only know that PCB can be built with a nice function, so, to understand the intricate relationship between copper thickness and circuit width and spacing is pivotal. These two parameters are like the gears of a well-oiled machine, interlocking in ways that significantly influence the printed circuit board‘s functionality, signal integrity, and manufacturability. If the designer does not consider the relationship between these two, the design may need to be modified in subsequent production.
In order to avoiding this information, let’s embark on a deeper exploration of this dynamic relationship to uncover its nuances and implications now,
Frist of all, we need to know some basic information about PCB, like copper thickness, circuit width and spacing.
The Essence of Copper Thickness
Copper, known for its exceptional electrical conductivity, is the lifeblood of any PCB. The copper thickness refers to the amount of copper deposited onto the board’s surface during fabrication. It’s the foundation upon which the traces, the intricate pathways that carry electrical signals, are built. The standard copper thickness is often measured in ounces per square foot (oz/ft²) or micrometers (Âľm). Common options include 1oz (35Âľm), 2oz (70Âľm), and even higher, it depends on customerâs requirement.
Circuit Width and Spacing
Circuit width and spacing, though often overlooked, are integral components that determine a PCB’s performance, integrity, and overall functionality. Circuit width refers to the dimension of the conductive traces, while spacing pertains to the distance between these traces. These seemingly simple dimensions have a profound impact on the PCB’s behavior.
Secondly, Unveiling the Intricate Relationship
The relationship between copper thickness, circuit width, and spacing is a sophisticated interplay of electrical properties, heat dissipation, and signal integrity. Let’s delve deeper into this complex web of interactions:
Current-Carrying Capacity and Copper Thickness: Copper thickness directly influences a trace’s ability to carry current without succumbing to overheating. Thicker copper translates to higher current-carrying capacity and reduced resistive losses. However, the trade-off is that wider traces are necessary to accommodate the increased copper thickness.
Resistance and Circuit Width: Wider traces exhibit lower resistance, which in turn reduces voltage drop and enhances the efficiency of signal transmission. Designers must strike a balance between trace width, copper thickness, and available board space.
Spacing and Unwanted Interactions: As circuit spacing decreases, the probability of unwanted interactions, such as crosstalk and electromagnetic interference, rises. Thicker copper can exacerbate these issues due to its larger cross-sectional area. Maintaining appropriate spacing between traces is pivotal to prevent signal degradation and maintain integrity.
Heat Dissipation and Trace Width: Thicker copper also aids in better heat dissipation, a crucial consideration for power-intensive applications. However, this can necessitate wider traces to manage the thermal load effectively.
Signal Integrity and Crosstalk: Smaller spacing reduces the risk of crosstalk, but it’s a double-edged sword. Thicker copper traces may introduce higher capacitance, altering impedance and potentially impacting signal integrity. This delicate balance requires careful consideration during design.
For now, we have known the relationship between them, how to develop a best design between the circuit width & spacing and copper thickness, which depends on whatâs you really want, the huge current or heat management? Following details should be considered if you want to develop the best circuit width & spacing.
Current Requirements: Start by understanding the current requirements of your traces based on the components and operational conditions. Selecting the appropriate copper thickness and trace width ensures the PCB can handle the anticipated loads.
Thermal Management: Thicker copper facilitates heat dissipation, which is advantageous for power-dissipating components. However, remember that it might necessitate wider traces to ensure effective heat transfer.
Manufacturability: While thicker copper can enhance current-carrying capacity and heat dissipation, it might pose manufacturing challenges. Consult with PCB manufacturers to align your design choices with their capabilities.
Signal Integrity Analysis: Utilize simulation tools to analyze signal integrity, especially when dealing with smaller spacing and thicker copper. These tools provide insights into impedance matching, potential crosstalk, and overall performance.
Flexibility VS Rigidity: While thicker copper enhances many aspects, it can impact the PCB’s flexibility, crucial for certain applications. Evaluate the mechanical demands of your project and strike the right balance.
Regarding metal core PCB in Best Technology, the copper thickness and its accordingly circuit width & spacing like below, furthermore, it would be better if you can let me know your copper thickness before checking your drawing, we will give you the best solution before formal production.
Copper thickness
Minimum circuit width
Minimum circuit spacing
0.5-2oz
0.25mm
0.23mm
3oz
0.35mm
0.3mm
4oz
0.4mm
0.38mm
(trace_design_guide_of_MCPCB)
Conclusion: Striking the Optimal Balance
The intricate relationship between copper thickness, circuit width, and spacing in PCB design embodies a delicate equilibrium that significantly influences a design’s performance and functionality. This nuanced interplay directly impacts parameters such as current-carrying capacity, resistance, heat dissipation, and signal integrity.
Achieving the optimal balance between these factors requires a deep understanding of electrical properties, thermal considerations, and signal behavior. Designers must carefully evaluate the specific requirements of their projects and leverage simulation tools to fine-tune their choices. Collaboration with PCB manufacturers ensures alignment with manufacturing capabilities.
The dynamic nature of this relationship underscores the constant evolution of PCB technology. As devices become smaller, faster, and more interconnected, the demand for intricate layouts intensifies. Designers must continuously adapt to new challenges, pushing the boundaries of what’s achievable while adhering to the fundamental principles that govern PCB design.
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.Â
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:
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.
When we talking about the holes in PCBs (Printed Circuit Boards), may somebody always curious about two special holes: Counterbore hole and Countersunk hole. They are easy to be confused and easy to misunderstanding if you are a layman of PCB. Today, we will introduce the differences between counterbore and countersunk for details, letâs keep reading!
What is a Counterbore Hole?
A counterbore hole is a cylindrical recess on a PCB that has a larger diameter at the top surface and a smaller diameter at the bottom. The purpose of a counterbore hole is to create space for a screw head or a bolt’s flange, allowing it to sit flush with or slightly below the PCB surface. The larger diameter at the top accommodates the head or flange, while the smaller diameter ensures that the fastener’s shaft or body fits snugly.
What is a Countersunk Hole?
On the other hand, a countersunk hole is a conical recess on a PCB that allows the head of a screw or bolt to sit flush with the PCB surface. The shape of a countersunk hole matches the profile of the fastener’s head, creating a seamless and level surface when the screw or bolt is fully inserted. Countersunk holes typically have an angled side, often 82 or 90 degrees, which determines the shape and size of the fastener head that will fit into the recess.
Counterbore VS Countersunk: Geometry
While both counterbore and countersunk holes serve the purpose of accommodating fasteners, their main difference lies in their geometry and the types of fasteners they accommodate.
Counterbore holes have a cylindrical recess with two different diameters, while countersunk holes have a conical recess with a single diameter.
Counterbore holes create a stepped or raised region on the PCB surface, whereas countersunk holes result in a flush or recessed surface.
Counterbore VS Countersunk: Fastener Types
Counterbore holes are primarily used for fasteners with a head or flange, such as bolts or screws that require a solid mounting surface.
Countersunk holes are designed for fasteners with a conical head, such as flathead screws or countersunk bolts, to achieve a flush surface.
Counterbore VS Countersunk: Drill angles
Different sizes and drilling angles of drill bits are offered for producing countersinks, depending on the intended use. These angles can include 120°, 110°, 100°, 90°, 82°, and 60°. However, the most frequently employed drilling angles for countersinking are 82° and 90°. For optimal outcomes, it is essential to align the countersink angle with the tapered angle on the underside of the fastener head. On the other hand, counterbore holes feature parallel sides and do not necessitate tapering.
Counterbore VS Countersunk: Applications
The choice between counterbore and countersunk holes depends on the specific requirements of the PCB design and the components being used.
Counterbore holes find applications in situations where a secure and flush fastening of components or mounting plates is necessary. They are commonly used to fasten connectors, brackets, or PCBs to an enclosure or chassis.
Countersunk holes are often employed when aesthetic considerations are important, as they provide a sleek and level surface. They are frequently used for mounting PCBs to surfaces where a flush finish is desired, such as in consumer electronics or decorative applications.
Counterbore and countersunk holes are important features in PCB design, enabling efficient component mounting and secure fastening. Understanding the differences between these two types of holes allows designers to select the appropriate option based on the specific requirements of their circuit board applications. Whether it’s ensuring a secure connection or achieving a visually pleasing finish, the choice between counterbore and countersunk holes plays a crucial role in the overall functionality and aesthetics of a PCB assembly.
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.
As the demand for higher power and miniaturization of electronics increases, so does the need for Heavy Copper Printed Circuit Boards (PCBs). From our last blog – Why choose Heavy Copper PCB for your High Current Project, we know the heavy copper PCBs are defined as those with copper thicknesses greater than 3 oz. These PCBs are designed to withstand high current and thermal loads, making them suitable for power electronics applications. However, the increased copper thickness also poses challenges during the solder mask printing process.
(16_layers_heavy_copper_PCB_with_10oz_each_layer)
Understanding solder mask
Solder mask (short for S/M in the industry) is a protective coating applied to PCBs to prevent solder bridges and improve solder joint quality. The solder mask is coated to the PCB surface using a screen-printing process, where the desired pattern is created using a stencil and the solder mask ink is then deposited onto the PCB. The ink is then cured, either through heat baking or UV light, to form a solid coating.
There are several types of solder mask materials available, including epoxy, acrylic, and liquid photo imageable (LPI) solder mask. Each type has its advantages and disadvantages, depending on the application requirements.
The benefits of using solder mask in PCB manufacturing include increased reliability, improved solderability, and reduced risk of short circuits and corrosion. The solder mask we usually use is Taiyo, which has high reliability and excellent heat resistance.
(Solder_mask_manually_printing)
Challenges in solder mask printing of heavy copper PCBs
While solder mask printing is a critical step in PCB manufacturing, the increased copper thickness in heavy copper PCBs presents several challenges for printing process as I mentioned before. Itâs difficult to apply enough solder mask to cover thick copper pattern and base material with severe height difference.
1. The high copper thickness and thermal conductivity of heavy copper PCBs make it difficult for the solder mask ink to adhere properly to the surface. This can result in insufficient coverage and registration accuracy, which can affect the overall quality and reliability of the PCB.
2. The high copper thickness can cause stress on the solder mask, leading to mask cracking and peeling. The navigation mark on the substrate has specific ink thickness requirements due to limitations in the ink thickness that can be applied to the substrate. If the ink thickness on the substrate is too thick, it may result in solder resist cracks in the substrate position after the printed circuit board is soldered. This can occur during reflow soldering or thermal cycling, resulting in poor solder joint quality and reduced reliability.
3. The thick solder mask is also more difficult to exposure and develop. If the exposure energy is too weak or not enough, then some undercut problem may happen.
How to overcome this challenge?
To address these challenges, it is essential to choose the right solder mask materials and optimize the application process.
Choosing the right solder mask materials is crucial for ensuring proper adhesion and coverage on heavy copper PCBs. LPI solder mask is often preferred for heavy copper PCBs due to its excellent adhesion and thermal stability. However, epoxy and acrylic solder mask materials can also be used with proper surface preparation.
Optimizing the solder mask application process can also help address the challenges of heavy copper PCBs. This can include using a thinner stencil for improved registration accuracy and applying multiple coats of solder mask for better coverage. Advanced solder mask technology, such as laser direct imaging (LDI), can also help improve registration accuracy and reduce the risk of mask cracking and peeling.
Optimizing the printing process, now in Best Technology, we always make the substrate first, fill the substrate with the solder mask and then treat it as a normal PCB for normal printing solder mask.
(Solder_mask_printing)
If you are in the process of designing a complex multi-layer heavy copper PCB and are looking for a high-quality and experienced manufacturer, feel free to reach out to us at sales@bestpcbs.com, Best Technology can support you by OEM and ODM service to ensure your design is cost-effective and can be easily manufactured.
In the world of electronics, printed circuit boards (PCBs) play a vital role in connecting and powering various components. They are the backbone of every electronic device, from smartphones to industrial machinery. When it comes to designing a PCB for a project, the thickness of the copper layer is an important consideration. Heavy Copper PCB, also known as Thick Copper PCB, has become increasingly popular in charging automotives due to their unique features and benefits. In this article, we will discuss why consider heavy copper PCBs for your high current project.
What a Heavy Copper PCB is?
A heavy copper PCB is a circuit board with an unusually thick copper layer, usually exceeding 3 ounces per square foot (oz/ft²). By comparison, standard PCBs typically have a copper layer thickness of 1 oz/ft². Heavy copper PCBs are used in applications where high current is needed, or the board needs to withstand mechanical and thermal stress.
(Heavy_copper_PCB)
Benefits of Heavy Copper PCBs
High Current Capacity
The thicker copper layer in a heavy copper PCB allows for a higher current capacity. This makes it ideal for high-power applications such as power supplies, motor controllers, and industrial equipment. Heavy copper PCBs can carry up to 20 amps or more, compared to the standard 5-10 amps of a regular PCB.
Thermal Management
Heavy copper PCBs are known for their excellent thermal management capabilities. The thicker copper layer allows for better heat dissipation, reducing the risk of overheating and component failure. So that they can generate a lot of heat for the end-application.
Durability
Heavy copper PCBs are more robust and durable than standard PCBs. The thicker copper layer provides better mechanical support, making them resistant to damage from vibration, shock, and bending. This makes them suitable for harsh environments and industrial applications.
Increased Flexibility
Heavy copper PCBs offer increased design flexibility compared to standard PCBs. The thicker copper layer allows for more complex and compact designs, reducing the overall size of the board. This makes them ideal for applications where space is limited, that means you can make a very heavy copper while the size is very small.
Better Signal Integrity
The thicker copper layer in heavy copper PCBs provides better signal integrity. This reduces the risk of signal loss and interference, resulting in more reliable and efficient circuit performance.
Copper thickness design for a Heavy Copper PCB?
Due to the thickness of copper in heavy copper PCB is thick then normal FR4 PCB, then it is easily to be warped if the copper thickness is not match each other in symmetrical layers. For example, if you are designing an 8 layers heavy copper PCB, then the copper thickness in each layer should follow L8=L1, L7=L2, L6=L3, L5=L4 standard.
Additionally, the relationship between minimum line space and minimum line width also should be considered, follow the design rule will help to smooth production and shorten the lead time. Below are the design rules between them, LS refers to line space and LW refers to line width.
(Heavy_copper_design_rule)
Drill hole rules for heavy copper board
A plated through hole (PTH) in printed circuit board is to connect top and bottom side to make them electricity. And when the PCB design has multi copper layers, the parameters of holes must be considered carefully, especially hole diameters.
In Best Technology, the minimum PTH diameter should be >=0.3mm while the copper ring annular should be 0.15mm at least. For wall copper thickness of PTH, 20um-25um as default, and maximum 2-5OZ (50-100um).
Here are some basic parameters of heavy copper PCB, hope this can help you to understand Best Technologyâs capability better.
Base material: FR4
Copper thickness: 4 OZ~30 OZ
Extreme Heavy Copper: 20~200 OZ
Outline: Routing, punching, V-Cut
Solder mask: White/Black/Blue/Green/Red Oil (Solder mask printing is not easy in heavy copper PCB.)
Surface finishing: Immersion Gold, HASL, OSP
Max Panel size: 580*480mm (22.8″*18.9″)
Applications of Heavy Copper PCBs
Heavy copper PCBs are used in a variety of applications, including:
Power supplies
Motor controllers
Industrial machinery
Automotive electronics
Aerospace and defense systems
Solar inverters
LED lighting
(Heavy_copper_PCB_for_high_power_supply)
Choosing the right PCB thickness is crucial for the success of any project. Heavy copper PCBs offer unique features and benefits that make them ideal for high-power and high-temperature applications. If you want to ensure the reliability and performance of your project, consider using heavy copper PCBs. Best Technology has more than 16 years manufacturing experience in heavy copper PCBs, so we are so confident that we can be your most reliable supplier in China. Welcome to contact us at any time for any questions or any queries about PCBs.
May some engineers or designers who be interested in thick film ceramic circuit are curious about can thick film ceramic boards design with via holes like FR4 PCB? Herein, we will explore the feasibility of using thick film ceramic boards for via holes, including the materials and processes involved, as well as the advantages of this approach.
What is thick film ceramic board?
The âThick Filmâ refers to the thickness of conductor layer on a Ceramic PCB. Normally the thickness will be at least 10um, around 10~13um, which is thicker than spurting technology in Thin Film Ceramic PCB. And of course thickness is less than DCB Ceramic board or FR4 board.
Thick film ceramic circuit enables to put resistor, electric capacitor, conductor, semi-conductor, and interchangeable conductor on ceramic board, after manufacturing steps of printing and high temperature sintering. The more important thing is by using thick film technology, we can make all the resistors with the same value, or different value for different resistor on the same board.
Materials and processes for via holes
In general, thick film ceramic circuit is not suitable for designing via holes. Because the characteristics of thick film ceramic board mainly depends on the insulation properties of its ceramic substrate, rather than conductive properties. The conductivity of thick film ceramic plate is not good than Metal Core PCB, or even we can say it has a very poor conductivity, usually canât meet the requirements of the via hole.
But, designing via holes in thick film ceramics is available in Best Technology. Generally speaking, the fabrication of via holes in thick film ceramic boards typically involves several key materials and processes.
From the designerâs perspective, a conductive material is used to create a continuous conductive path from one side of the ceramic board to the other. Common conductive materials include gold paste, silver paste, and copper paste. These materials are usually screen printed onto the ceramic board in the desired pattern, and then fired at high temperatures to achieve sintering and form a conductive layer.
Once the conductive layer is formed, the via holes are created by drilling or punching small holes through the ceramic board at the desired locations. These holes are then filled with a conductive material, such as silver paste or copper paste, to establish electrical connections between the different layers of the circuit.
Finally, the via holes are fired again at high temperatures to achieve sintering and ensure good adhesion and electrical performance.
Advantages of Via Holes in Thick Film Ceramic Boards
These via holes offer several advantages in the design and fabrication of thick film ceramic boards, including as following:
Electrical connectivity
Via holes provide electrical connectivity between different layers of a thick film ceramic board. They allow for the interconnection of different circuitry or conductive layers, enabling the flow of electrical signals or power between different parts of the board. This allows for complex and multi-layered circuit designs, which can be highly beneficial in applications that require intricate circuitry or high-density interconnects.
Space-saving
Via holes can provide a means of vertical interconnection, allowing for more efficient use of board real estate. Instead of routing traces or conductors on the surface of the board, which can take up valuable space, via holes can be used to route connections through the board, freeing up surface area for other components or functions. This is especially advantageous in compact or miniaturized electronic devices where space is limited.
Thermal management
Via holes can aid in thermal management in thick film ceramics. They can be used to transfer heat from one layer of the board to another, helping to dissipate heat generated by components or circuits. This can be particularly important in high-power or high-heat applications, where efficient thermal management is crucial for preventing overheating and ensuring reliable performance.
Mechanical stability
Via holes provide additional support and reinforcement to the board, reducing the risk of warping, bending, or cracking. Via holes can also help improve the overall mechanical integrity of the board by reducing stress concentration points and enhancing its structural rigidity.
Design flexibility
Via holes offer design flexibility in thick film ceramic boards. They can be designed and placed according to the specific requirements of the circuit or system, allowing for customized and optimized designs. Via holes can be used to route traces, create vias for component mounting, or provide grounding or shielding, among other functionalities. This flexibility in design allows for more efficient and effective circuit layouts, which can lead to improved performance and reliability.
As previously mentioned, designing via holes in thick film ceramic boards offers various benefits. However, when it comes to choosing the appropriate paste for via holes, silver paste is often recommended to our customers. But why is that? Can I use gold or copper? In our upcoming article, we will delve into the reasons behind this recommendation and provide you with valuable insights. Stay tuned to uncover the answers!
There are many places in the Printed Circuit Board Design that need to consider the safety spacing, here we summarized Eight Safety Spacings in total to show you what spacing we should pay attention to when designing, they can be separated into two categories, one is Electrical-Related Safety Spacing, and another is Non-Electrical-Related Safety Spacing.
Electrical-Related Safety Spacings
Wire Spacing
As far as the processing capability of the mainstream PCB manufacturer is concerned, the spacing between the wires shall not be less than 0.075mm. The minimum line distance refers to line to line, line to pad space. From a production perspective, the larger the better, and the more common wire spacing is 0.25mm by far.
Diameter and Width of Pad
From the processing capability of mainstream PCB manufacturers, the minimum diameter shall not less than 0.15mm if the holes on pad requires mechanically drilled. If used laser drilling, then hole diameter must greater or equal than 0.10mm. At the same time, the tolerance of hole diameters varies slightly according to different substrates. Generally, it can be controlled within 0.05mm, and the minimum width of the pad should not be less than 0.2mm.
Spacing between Pad to Pad
The spacing between pads must be at least 0.2mm as far as the processing capacity of mainstream PCB manufacturers concerned.
Copper and Edge of the Board Spacing
The spacing between electronic copper and edge of the board should be no less than 0.30mm, and it can be set spacing rule on the âDesign â Rules – Board outlineâ page.
If it requires a larger area of copper, it is generally needs to set 0.5mm as a retraction spacing from the edge of board. In the PCB design and manufacturing industries, engineers often shrink the large area of copper coating to the edge of the board by 20mil for mechanical considerations of the finished circuit board, or to avoid the occurrence of curling or electrical short circuit caused by the exposure of copper on the edge of the board, rather than coating whole copper to the edge of the board.
There are many methods to handle such shrink problems, such as drawing a keepout layer and then set a distance between copper and the keepout. As a professional PCB manufacturer that have rich experience over 16years, there is a much easy way to set different safety spacings for copper objects. For example, the safety spacing of the whole board set as 0.25mm, then we can set copper to 0.5mm, which can achieve a shrink distance of 0.5mm, and the dead copper that may cause in some devices also can be removed as well.
Non-Electrical-Related Safety Spacing
Width, Height and Spacing of Legends
We canât make any changes during the processing of text legend film, except that the line width of legend with D-CODE less than 0.22mm (8.66mil) is enlarged to 0.22mm, that is, the line width of legends L=0.22mm (8.66mil).
The width of the whole charact legends W=1.0mm, the height of the whole legends H=1.2mm, the spacing between the legends D=0.2mm. When the text is less than the above standard, the text legends after printing will be blurred.
Spacing between Via to Via
The spacing between vias to vias is preferably not less than 8mil.
Spacing between Legend to Pad
Legends/Silkscreens are not allowed on the pads, otherwise, the covered area canât be tinned and which will affect the assembly process finally. Generally, manufacturer requires a 8mil space to convenient for silkscreen printing, but if your PCB is small and limited in area, it is barely acceptable to leave a 4 mil safety space.
If some legends accidentally over the pads in your design, Best Technology will remove or move to another area when get your approval to ensure good tinned.
Of course, design on a case-by-case situation. Sometimes the screen printing is deliberately close to the pad, because when the two pads are very close, the screen printing in middle can effectively prevent the short circuit of the solder connection during soldering, and this is another case.
Mechanical 3D height and Horizontal Spacing
When mounting the components on the PCB surface, it is necessary to consider whether there will be conflicts with other mechanical structures in horizontal direction and spatial height. Therefore, in the PCB design, the compatibility between components, finished products and product outer house and spatial structure should be fully considered, and the safety spacing should be reserved for each target object to ensure there is no conflicts occur in space.
In summary, there are many data and key points should be pay highly attention to while in PCB designing, Best Technology manufactures varies of good quality PCBs for our customers, so please do not hesitate to contact us when you have PCB design, we can help to evaluate it freely for you.
Printed circuit board is used to power up the electronic devices, and the legend on its surface been known as legend text or silkscreen text to be aim at providing vital information to electronic manufacturers or end users. This post is a guideline to help you understand what information we can gain from those legends and what we need to pay attention to when design them.
A brief introduction about PCB legend
Though a printed circuit board doesnât require any legend/text to function technically, the text provides key information to end users to test, assemble and troubleshoot, and generally we can obtain following information from the legends:
Branding information
This includes manufacturerâs information, serial numbers, date code and other information, which prevents the copying of design.
Part number provided
Part numbers are added on the circuit boards to enable replacement or design evolution whenever needed.
Version of product
Sometimes versions were updated, and the legend is added on the circuits to identify the specific version and backtrack the date.
Reference of components indicators
This may feature components information such as indicators, orientations and other information.
Safety Precautions
These are warning signals that are added to protect users from electric shocks. A few examples of these may include grounding, high voltage, and so on.
Circuit Identification
Users and designers can identify circuit names from legends to understand testing points, ground points, component interconnect, so forth.
Polarity indicator for certain components
Some components such as diodes, LED chips, electrolytic capacitors require to a distinguish of polarity when assembly, text legends help to indicate the right polarity to ensure assembled correctly and perform functionality when reach to consumers.
Authentication indication
Silkscreen text shows the boards are authenticated or conforms to certain security certification, such as RoHS, 94V-0, ULâŚ
Test points and troubleshooting assistants
Help to correctly perform testing including resistance measurement, voltage measurement, function testing and so forth. In addition, text legend enables to troubleshoot while issues or debugs happened and repair is required.
Component outlines indicating where components should go
Legends provides a great help during assembly process, it helps the operator quickly find where each component should be, so it is recommended to add text legends when PCB need to be assembled.
General Parameters for PCB Legend in Best Technology
To understand the capabilities of legend printing of Best Technology, here we listing some general parameters for your reference:
Legend colors can be white, black, green, yellow or other colors depend on customerâs preferences.
Legend line width is range from 5mil to 7mil
Text height can set at 30mil
Maximum text width can be 17mil
Printing methods are screen printing, direct legend printing and Liquid photo imaging. (Direct legend printing is commonly used by far.)
Important factors need to be considered during designing
Although legends are easy to be printed, there are still some key points need to pay highly attention when you are designing.
Legend orientation: To maintain a good reading appearance for user, please make sure all legends throughout the board have a same orientation.
Choose a standard color and shapes for marking, this is a most economy way to save cost.
Avoid overlapping: Overlapping is one of the most common problems that manufacturer faced. Legend always be related to PCB layout, and components reference will be also designated when circuit board layout finished. So if the legend was overlapped, it must be moved to another place and that may cause component reference was located in a wrong position, so it is always recommend to double check all the legends, to make sure they are clear and in the correct position when the whole board layout was completed.
Do not place the silkscreen text on all four directions, this will lead to confusions when the circuit board is undergoing repair.
Leave a few mils space for some common potential printing errors, this will help manufacturer to reduce the possibility of errors.
Every PCB manufacturer has its unique style and pattern when it comes to legend printing, so working files confirmation plays an important role before circuit fabrication, Best Technology gives a great respect to the original files to our customers, we wonât start production until get approval of working files from customers, so please do not worry about it if you have such concerns. In addition, as a professional printed circuit board manufacturer in Asia, we are confident that we can provide you with high quality PCB, welcome to contact us if you have PCB needs.
