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What Are Vias on Printed Circuit Board (PCB)?
Friday, May 31st, 2024

In PCB design, engineers often use via holes to connect the same electrical network located in different layers, vias and through holes PAD is very similar, the difference is that through holes pad is generally used to insert plug-in components, while via holes are generally small. Vias are very popular in some complex and multi-layer design, because it can serve as a pathway between the different layers.

What are vias in printed circuit boards (PCBs)?

Vias in printed circuit boards (PCBs) are essentially small holes that are drilled or etched into the board’s surface.  These small, cylindrical holes are plated with conductive material, typically copper, to ensure electrical continuity between the layers. They serve as conduits for electrical connections between different layers of the PCB or between components mounted on the surface of the board and the internal circuitry.

They are important for creating multilayer PCBs, where multiple layers of copper traces are separated by insulating layers. Without vias, it would be impossible to establish connections between these layers, limiting the complexity and functionality of electronic devices.

A via hole in PCB is mainly composed of three parts, hole, pads around the holes, and power layer isolation area. The process of via hole is to plate a layer of copper foil on the cylindrical surface of the hole wall by chemical deposition to connect the copper foil that needs to be connected in the middle of each layer. In this way, the upper and lower sides of the hole are made into ordinary pad shape, which can be directly connected with the traces of the upper and lower sides. The wall thickness of the plating is 1mil or 2mil, and completed hole diameter may be 2mil-4mil smaller than the drilled hole.

vias on pcb

Why Employ Vias in PCBs?

Vias in PCBs primarily facilitate electrical connections across different board layers, enabling designers to craft intricate and compact circuit layouts by permitting signal and power traversal through layers. This capability is paramount in multi-layer PCBs, where space is constrained, and high-density component placement is requisite.

  • Space Optimization

Vias permit the stacking of multiple circuit layers, optimizing PCB real estate, resulting in more compact devices.

  • Enhanced Electrical Performance

Providing direct electrical signal pathways, reducing interference and loss, thereby enhancing overall circuit performance.

  • Thermal Management

Thermal vias, specifically engineered for heat dissipation, aid in managing PCB temperatures, ensuring component reliability and longevity.

  • Design Flexibility

Vias afford greater flexibility in routing traces and component placement, fostering more innovative and efficient PCB designs.

What are the different types of vias used in PCB design?

There are several types of vias, each serving different purposes based on their placement and function. Understanding the different types and their applications is crucial for designing efficient and reliable PCBs. The most common types include through-hole vias, blind vias, and buried vias. Each offers unique advantages depending on the design requirements and constraints of the PCB.

1. Through-Hole Vias: These are the most common type of vias, extending through the PCB’s entire thickness, linking all layers. They are straightforward to manufacture and cost-effective.

2. Blind Vias: These vias connect an outer layer of the PCB to one or more inner layers but do not go through the entire board. They conserve space and simplify board layout complexity.

3. Buried Vias: Located entirely within the inner layers of the PCB, buried vias connect two or more internal layers without reaching the outer surfaces. They are useful for high-density and multi-layer PCBs where space is limited.

vias on pcb

4. Micro Vias: Smaller than standard vias, micro vias are typically utilized in high-density interconnect (HDI) PCBs. They can connect adjacent layers or span multiple layers using stacked or staggered configurations.

What is the difference between a PCB hole and a via?

The terms “PCB hole” and “via” are often used interchangeably, yet they denote distinct features within a PCB:

PCB hole generally refers to any drilled PCB hole, serving various purposes such as mounting components (e.g., plug-in components), positioning holes or mechanical mounting points. PCB holes are not necessarily conductive. While vias specifically denotes a conductive hole connecting different PCB layers. They are plated with conductive materials, usually copper, to ensure electrical continuity between layers.

In essence, while all vias are PCB holes, not all PCB holes are vias. Vias are a subset of PCB holes with the specific function of establishing electrical connections between layers, whereas PCB holes can serve a broader range of purposes, including mechanical and non-electrical functions.

vias and holes

What should we consider when designing vias in PCB?

In a PCB design, seemingly simple via holes often bring great negative effects to the design of the circuit. In order to reduce the adverse impact of the parasitic effect of the hole, PCB engineers can try their best to consider below points:

  1. Vias cannot be designed on the pads.
  2. The area extending 1.5mm outward from the contact region between the device’s metal housing and the PCB should not design any vias.
  3. Vias should not be present in the areas where adhesive dots are applied or printed for surface-mount components, such as the PCB areas beneath CHIP and SOP components when using adhesive dot application or printing processes.
  4. In principle, through-hole diameters should be at least 0.2mm (8mil) with an outer diameter of at least 0.4mm (16mil). For some special areas, the outer diameter must be controlled to 0.35mm (14mil).
  5. For BGA designs with a pitch of 0.65mm and above, it is advisable to avoid using blind or buried vias, as they significantly increase costs.
  6. The spacing between vias should not be too close to prevent drilling from causing breaks. Generally speaking, the hole spacing should be 0.5mm or more. Spacings of 0.35mm-0.4mm should be avoided as much as possible, and spacings of 0.3mm or less are prohibited.
  7. The number of vias used for power trace inter-layer connections should meet the current carrying requirements, which is 1A per 0.3mm diameter via.

This is the end of this informational sharing, welcome to contact us if you want to know more about PCBs.

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What is the Flexible Aluminum PCB?
Wednesday, May 29th, 2024

Flexible aluminum PCB is a new development in the recent years, it enables people decrease the size of certain products in some area. Different from the rigid flex PCB, flexible aluminum PCB combines the flex circuit and aluminum core circuit board (or can be copper core PCB), so it has the rigidity and good thermal management of traditional Aluminum PCBs with the flexibility of polyimide, these hybrid boards offer a host of advantages.

To increase the thermal conductivity in high power applications, and meet the flexibility requirements, flexible aluminum PCB is a good option. This article explores the key benefits of flexible Aluminum PCBs, highlighting why they are becoming increasingly popular in various applications.

flexible aluminum pcb

What is Flexible Aluminum PCB?

Flexible aluminum PCBs are a type of printed circuit board that uses an aluminum base material and is designed to be flexible. Unlike standard aluminum PCBs, these boards can bend and conform to different shapes, making them ideal for applications where space and flexibility are crucial. And Have you ever heard about our another aluminum board that we called bendable aluminum PCB? This is a special metal core circuit board that uses special material makes the circuit board bendable while won’t damage the board. May you think both of two are the same product? No, they are different in the constructure and raw materials, and the manufacturing processes are different as well.

Bendable aluminum PCB uses aluminum alloy as the raw material, considering it must meet the bendable requirement as well as the good thermal management during using, it must be specially designed aluminum alloy composite material. And the aluminum base thickness also is a key consideration, 0.2mm to 1.0mm always are the common bending metal substrate thickness. Meanwhile, the bending radius of bendable aluminum PCB also should be calculated before manufacturing, making it follow the bending design standard to smooth the manufacturing. It is the same as flexible aluminum PCB.

bendable aluminum pcb

What Are the Constructure of Flexible Aluminum PCB?

Flexible aluminum PCBs combine the benefits of aluminum’s excellent thermal management with the flexibility required for modern electronic designs. These PCBs are constructed using a combination of materials and layers that provide flexibility, durability, and efficient heat dissipation. And compared with original aluminum PCB, it adds the flexible insulation layer and the content of adhesive glue is different.

  • Aluminum base layer

The aluminum base layer serves as the foundation of the flexible aluminum PCB. It provides structural support and excellent thermal conductivity. Typically, high-quality aluminum is used for this layer due to its superior thermal properties and mechanical strength.

  • Dielectric layer

It acts an insulator between the aluminum base and copper foil, it can allow the heat pass through while electrically insulating the conductive pathways.

  • Copper foil

The copper foil forms the conductive pathways that carry electrical signals and power across the PCB. It is essential for the functioning of the electronic components connected to the PCB.

  • Flexible layer

Common materials for this layer include polyimide (PI) or polyester (PET), both known for their flexibility, thermal stability, and insulating properties. It contributes to the overall flexibility of the PCB, allowing it to bend and conform to various shapes.

  • Protective overlayer

This layer is applied over the copper circuits to protect them from environmental factors such as moisture, dust, and physical damage. It also provides mechanical support to the flexible areas. Normally called solder mask layer.

The Difference Between Flexible Aluminum PCB and Flex Circuits

While both aluminum flex PCBs and flexible printed circuits (FPCs) offer flexibility, they differ significantly in their materials and manufacturing costs:

ItemFlexible Aluminum PCBFlex Circuit (FPC)
Base MaterialAluminum corePolyimide or PET
Conductive MaterialCopper foil and aluminum for the conductive tracesVarious materials like polyimide, PET or the copper foil
FlexibilityLimited in specific areaFlexible everywhere
Thermal ConductivityHigh thermal conductivityDepends on the material used
Manufacturing ProcessComplexRelatively simple
Specific AdvantageFast heat dissipationGeneral part in electronics
(Comparison between flexible aluminum PCB and flex circuit)

What Are the Benefits of Using Flexible Aluminum PCB?

Flexible aluminum PCB has numerous advantages that make it highly preferrable for specific applications, including:

  • Excellent thermal management

Due to the applied of aluminum base, efficient heat dissipation prevents overheating and extends the lifespan of electronic components.

  • Lightweight and flexible design

Due to the flexible and lightweight features in the flex aluminum PCB, it can be bent and shaped the PCB reduces the need for additional connectors and saves space in compact designs.

  • Improve reliability

Aluminum based PCB has good durable, ensures the long-lasting performance of the whole product, even in harsh conditions.

  • High density integrated

The flexible aluminum PCB allows for the higher density circuit layouts than normal aluminum PCB.

  • Effective electromagnetic shielding

Aluminum material provides electromagnetic shielding in a certain degree, which helps to reduce the impact of electromagnetic interference on the circuit.

flexible aluminum pcb

How to Choose A Reliable Flexible Aluminum PCB Manufacturer?

Selecting the right manufacturer for flexible aluminum PCBs is crucial for ensuring quality and reliability. Make sure your supplier has extensive experience in this field and obtained relevant certifications like UL, CE, ISO9001 and so on.

Best Technology is a China-based PCB and PCBA manufacturer, who has over 17-years-experience circuit board manufacturing. At Best Technology, we specialize in providing high-quality flexible aluminum PCBs tailored to meet your specific needs. And we were certificated by ISO9001 quality control system, ISO13485 for medical device and IATF16949 for automotive system. Our expertise and commitment to excellence ensure that you receive the best solutions for your electronic applications. Choose Best Technology for your PCB requirements and experience the benefits of advanced PCB technology.

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What is the Rogers Printed Circuit Boards?
Monday, May 13th, 2024

Rogers Printed Circuit Board (short for Rogers PCB) is a printed circuit board (PCB) manufactured using a special high-frequency material produced by Rogers Corporation. These boards are designed to meet the demanding performance requirements of high-frequency electronic devices, especially in wireless communications, microwave technology, high-speed digital signal processing, radio frequency (RF) products, and applications requiring extremely high stability and low signal loss.

Rogers pcb made by best technology

What are the Main Features of Rogers Printed Circuit Board?

Rogers boards are made of a proprietary amide resin material, which gives them excellent dielectric properties, thermal stability and mechanical strength. Even in extreme working environments such as high temperature and humidity, high frequency and high speed, Rogers PCB board can maintain stable operation, showing its strong adaptability and reliability. Whether it is to improve the performance of electronic equipment, or to ensure the stability of the system, Rogers PCB board plays a vital role. Below are some main features and benefits of Rogers PCB.

  • Special substrates

Unlike traditional PCB materials based on glass fiber reinforced epoxy resins such as FR-4, Rogers PCBs are ceramic filled or based on high-performance substrates such as liquid crystal polymers (LCP), for example, RO4350B, RT/duroid series, TMM series and TC series. These substrates provide excellent electrical properties, such as low dielectric constant (εr) and low dielectric loss factor (Df), ensuring low signal loss and high-speed during transmission.

  • High frequency performance

Rogers PCB is particularly suitable for high frequency applications, because its material characteristics make the circuit board can maintain extremely low signal attenuation and stable electrical performance at operating frequencies up to tens or even hundreds of GHz. This makes them excellent in radar systems, satellite communications, 5G/6G network equipment, radio frequency identification (RFID) systems, high-speed data transmission interfaces (such as USB, PCIe) and other applications.

  • Temperature stability

Rogers material has excellent thermal stability and low coefficient of thermal expansion (CTE), which matches the thermal expansion rate of copper foil, helping to reduce the stress and deformation caused by temperature changes, ensuring the reliability of the circuit when working in a wide temperature range.

  • Mechanical strength and heat resistance

Due to the use of high-performance composite materials, Rogers PCB usually has high mechanical strength and good high temperature resistance, and can adapt to harsh environmental conditions and heat dissipation requirements.

  • Surface treatment

Rogers PCB can carry out a variety of surface treatments, such as gold plating, silver plating, organic welding film (OSP), etc., to meet the specific requirements of different applications for weldability, oxidation resistance, contact resistance, etc.

  • Multi-layer structure and fine traces

Rogers PCB can be made into single-layer to multi-layer structure, support high density interconnect (HDI) design, with fine lines (such as line width/line distance up to 0.3mm or smaller) and small aperture (such as 0.3mm), suitable for complex and precise high-frequency circuit design.

  • Low moisture absorption

Rogers material moisture absorption rate is very low, even in high humidity environment can maintain stable electrical performance, reduce the impact of moisture on dielectric properties, to ensure long-term reliability. In summary, Rogers printed circuit board is a high-end, professional-grade circuit board product, with its excellent high frequency characteristics, stable electrical performance, excellent temperature stability, and wide applicability, becoming the ideal choice to meet the demanding requirements of modern high performance electronic equipment and communication systems.

Why Use Rogers Printed Circuit Boards?

High frequency PCBs often need high performance with low signal losses, low electrical noise, or high board temperatures. To meet this need Rogers Corp. PCB materials are often used as they are cost effective vs. many of the alternatives. Here are some typical Applications for Rogers PCB:

All kinds of the Microwave equipment.

5G Cellular Base Station Antennas and Power Amplifiers

Automotive Radar and Sensors

RF Identification (RFID) Tags

Direct Broadcast Satellites for low noise block downconverter

Medical equipment such as monitoring instrument, cardiac pacemaker, MRI, etc.

Military and aerospace

Rogers pcb made by best technology

Rogers series is often used in RF PCBs with frequencies 6+ GHz and in high heat applications that need ceramic laminates and low signal losses. It may also be used to minimize electrical noise to meet stringent performance requirements.

In our next blog from Best Technology, we are going to share more information about different material from Rogers PCB. pls follow us and if you want to know more about the Rogers PCB, warmly welcomed to visited www.bestpcbs.com or email us, it would be our great pleasure to answer all the questions for Rogers PCB.

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What Are Stamp Holes and What’s the Design Standard About It?
Monday, May 6th, 2024

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 what’s 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 “stamp holes”.

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.

stamp holes on pcb

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.

stamp holes on pcb

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 don’t 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.

stamp holes on RF pcb

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.

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