Layer Stackup: Determine the layer count, material selection for each layer, and the overall layer stackup to meet signal integrity, impedance control, and thermal management requirements. Consider the arrangement of power and ground planes for optimal signal integrity and EMI/EMC performance.
Signal Integrity: Proper trace routing, controlled impedance, and minimizing signal coupling are critical for maintaining signal integrity, especially in high-speed digital and high-frequency analog circuits. Crosstalk mitigation and transmission line design should be carefully addressed.
Power Integrity: Ensure the distribution of power and ground planes, managing power delivery network (PDN) impedance, and minimizing voltage drop across the PCB for stable power distribution.
Thermal Management: Implement strategies for heat dissipation, including the placement of thermal vias, copper pours, and the location of heat-generating components with adequate spacing and access to airflow.
Manufacturability: Design for manufacturability by following industry-standard design rules for minimum trace width, spacing, and annular ring sizes, as well as considering the capabilities and limitations of the chosen PCB fabrication and assembly processes.
Component Placement: Optimize component placement for signal integrity, thermal management, and ease of assembly. Consider the orientation of components, high-speed signal paths, and thermal hotspots.
Routing: Implement efficient and optimized routing to minimize signal length, impedance mismatches, and EMI issues. Route high-speed signals first and use differential pairs where applicable.
EMI/EMC Considerations: Incorporate EMI/EMC mitigation techniques such as via stitching, shielding, and careful placement of sensitive and high-speed traces to minimize electromagnetic interference.
Via Placement: Strategically place vias to maintain signal integrity, provide thermal relief, and optimize power and ground connections.
Compliance and Standards: Ensure compliance with relevant industry standards and regulations governing PCB design, including safety, EMI/EMC, and environmental considerations.
By addressing these key considerations, designers can create multi-layer PCBs that meet stringent performance requirements, offer high reliability, and are conducive to efficient manufacturing and assembly processes.
]]>With these tips in mind, remain iterative in your design process. Test often, seek feedback, and embrace the fact that PCB design is an ever-evolving field where continuous learning and adaptation are the keys to success.
]]>Blind vias are a type of via used in printed circuit board (PCB) design and manufacturing. They differ from traditional through-hole vias because they do not extend through the entire PCB.
Instead, they only go through one layer of the PCB and are often used to connect the inner layers of a multilayer PCB without breaking through to the opposite side of the board. This can be useful for reducing the overall size of the PCB and for hiding the vias from view.
Blind vias are often used in flexible PCBs, which are PCBs that are made from flexible, bendable materials such as polyimide. Flexible PCBs are helpful in various applications, including in electronic devices where the PCB needs to be adjustable to fit into a particular shape or be able to move or bend.
One challenge in using blind vias in flexible PCBs is that the vias must withstand the stress and strain of the bent or flexed PCB. This requires careful design and manufacturing of the vias, as well as the use of strong and flexible materials to withstand the forces applied to the PCB.
One way to increase the strength and flexibility of blind vias in flexible PCBs is to use laser drilling to create the vias. Laser drilling is a precise, high-tech method of creating small holes in a PCB, and it can be used to create blind vias with very small diameters and high aspect ratios (the ratio of the depth of the via to its diameter).
Another option is to use flexible materials for the via fills, which can help to reduce the stress on the vias when the PCB is bent or flexed. For example, a flexible resin or conductive ink can be used to fill the vias, which can help to distribute the stresses more evenly throughout the via and reduce the risk of the via breaking or becoming damaged.
Buried via flexible printed circuit boards, also known as BVFPCBs, are a type of flexible circuit board with vias (conductor pathways) buried within the layers of the board. These vias are not visible from the board's surface and are typically used to connect different circuit board layers.
One of the main benefits of using BVFPCBs is their ability to improve a circuit board's overall reliability and performance.
Since the vias are buried within the layers of the board, they are protected from external damage and are less likely to experience issues such as short circuits or breaks in the circuit.
This makes them ideal for use in harsh environments or applications where the circuit board may be subject to physical stress or exposure to contaminants.
In addition to their reliability, BVFPCBs also offer several other advantages. They are more flexible than traditional circuit boards, which makes them easier to bend and shape to fit into tight spaces or conform to curved surfaces.
This can be especially useful in applications where the circuit board needs to be flexible or conform to a specific shape.
BVFPCBs are also lightweight and thin, making them ideal for portable or compact electronic devices. They are also more cost effective than traditional circuit boards, requiring fewer layers and less material to manufacture.
Overall, buried via flexible printed circuit boards are a highly reliable and versatile option for a wide range of electronic applications. They offer improved performance, flexibility, and cost savings, making them an attractive choice for manufacturers and designers.
Blind and buried vias are interconnects used in flexible printed circuit boards (PCBs). These vias are not visible on the top or bottom surfaces of the PCB and are instead buried within the layers of the board. This allows for a more compact design, increased routing density, and improved signal integrity.
One of the main advantages of using blind and buried vias in flexible PCBs is their ability to provide increased routing density. This means that more components can be placed on the board, making it possible to create smaller, more compact devices.
Additionally, using blind and buried vias can help to improve signal integrity by reducing the distance that signals travel, resulting in better performance and more reliable operation.
However, some challenges are associated with using blind and buried vias in flexible PCBs. One of the main challenges is that these vias are more difficult to manufacture, as they require specialized equipment and processes.
Additionally, the use of blind and buried vias may increase the cost of the PCB, as they are more expensive to produce than other types of interconnects.
Despite these challenges, the benefits of using blind and buried vias in flexible PCBs often outweigh the costs.
These vias allow for more compact designs, increased routing density, and improved signal integrity, all critical factors in the design and performance of modern electronic devices. As such, they are likely to continue to be an important part of the flexible PCB industry in the coming years.
A flexible PCB stackup is the arrangement of layers in a flexible PCB. These layers can include conductive, dielectric, and adhesive layers and blind vias for interconnections. The stackup is important for determining the overall performance and reliability of the PCB.
One of the key benefits of using blind vias in a flexible PCB stackup is their ability to reduce the number of layers required. This is because the vias can interconnect layers that are not visible on the surface, allowing for a more compact design. This can also help to reduce the overall cost of the PCB, as fewer layers mean less material and labor required.
Another advantage of using blind vias in a flexible PCB stackup is their ability to improve the flexibility of the PCB. By using blind vias to interconnect layers, the PCB can be more easily bent and flexed without damaging the connections. This can be especially important in applications where the PCB will be subjected to stress or movement, such as in wearable or medical devices.
There are a few considerations to keep in mind when using blind vias in a flexible PCB stackup. One of these is the size of the vias, as larger vias may be more prone to failure or damage when the PCB is flexed. It is also important to carefully plan the routing of the vias to ensure they do not interfere with other components or structures on the PCB.
Overall, blind vias are a useful tool for designing flexible PCBs, allowing for a more compact and flexible stackup. They can reduce the number of layers required and improve the flexibility of the PCB, making them a valuable consideration for any design engineer.
Blind Via Flexible PCB material is a printed circuit board used to manufacture electronic devices. This type of PCB is made using a flexible material such as polyimide or polyester, which allows it to be bent or flexed without damaging the circuitry.
One of the main advantages of using a Blind Via Flexible PCB is its ability to be used in many applications. This type of PCB is often used in devices that need to be portable or have a small form factor, such as smartphones, tablets, and wearable devices. It is also used in medical devices, military equipment, and aerospace systems.
One of the key features of a Blind Via Flexible PCB is its ability to connect different layers of the circuit board without the need for through-hole vias. This is known as a "blind via," and it allows for more efficient and compact circuit board design. This is especially useful in devices with multiple layers of circuitry, as it reduces the amount of space required for the vias and allows for more complex designs.
Another advantage of Blind Via Flexible PCBs is their improved performance and reliability. Because the vias are not exposed to the surface of the circuit board, they are less prone to damage and failure. This makes them ideal for use in applications where durability and reliability are critical, such as in military and aerospace systems.
In addition to their functional benefits, Blind Via Flexible PCBs also offer several manufacturing advantages. They are easier to manufacture than traditional PCBs, requiring fewer steps and materials. This makes them more cost-effective to produce and allows for faster turnaround times.
Blind Via Flexible PCBs are a versatile and reliable option for electronic device manufacturers. They offer a range of benefits, including improved performance, compact design, and cost-effectiveness, making them an ideal choice for a wide range of applications.
Blind buried vias are a type of via used in flexible printed circuit board (PCB) manufacturing. They are called "blind" because they do not go all the way through the PCB and are "buried" because they are hidden beneath the surface layers of the PCB.
This allows for a more compact design and more space on the surface for components and other features. The "via in pad" fabrication process refers to placing these vias within the pads (or areas designated for components) on the PCB.
There are several steps involved in the blind, buried vias flexible PCB via in-pad fabrication process:
The design and layout phase of the blind, buried vias flexible PCB via the in-pad fabrication process is crucial in ensuring the final product meets the desired specifications and functions properly. During this phase, a detailed plan is created for the circuit board, including the placement of all components, traces, and vias. The design should consider the PCB's flexibility and the board's desired final shape and size.
Once the design is complete, it is important to carefully review and verify it to ensure that all components are placed correctly and that the trace routing is efficient and free of errors. Any errors or inconsistencies discovered during this phase can be corrected before moving on to the next steps in the fabrication process.
The design and layout phase also involves creating a photolithographic mask, a negative image of the circuit board that will be used to transfer the design onto the PCB material. The mask is created by exposing a light-sensitive film to UV light through a patterned mask, which causes the film to harden in certain areas. The accuracy of the photolithographic mask is critical in ensuring that the final PCB accurately reflects the design.
Overall, the design and layout phase is a critical step in the blind, buried vias flexible PCB via the in-pad fabrication process, as it sets the foundation for the rest of the process and determines the outcome of the product. Ensuring a complete and accurate design and layout can save time and resources in the long run and result in a high-quality, functional PCB.
The etching process involves removing unwanted material from the PCB using a chemical etchant. This is done to create the desired circuit patterns and features on the PCB.
Etching is a crucial step in the blind, buried vias flexible PCB via the in-pad fabrication process, as it involves creating the vias themselves. This process uses two main methods: chemical etching and laser drilling.
Chemical etching involves immersing the PCB in a solution that removes the copper in the areas defined by the etch mask, creating the vias. This process is typically used to create larger vias and requires careful control of the etching solution and the amount of time the PCB is immersed.
Laser drilling creates smaller, more precise vias and is typically used in conjunction with chemical etching. In this process, a high-energy laser beam is used to create small holes in the PCB, which are then enlarged and connected using the chemical etching process. Laser drilling is a precise and efficient method for creating small vias, but it can be more expensive than chemical etching.
Regardless of the method used, etching requires careful attention to detail and precise execution to ensure proper connections and performance. Any errors or defects in the etching process can affect the overall performance of the PCB and may require rework to correct.
The formation of vias in a flexible printed circuit board (PCB) is an important step in the via-in-pad fabrication process. Vias are small holes that allow connections between different layers of the PCB and are typically filled with a conductive material to ensure proper electrical conductivity.
In the case of blind buried vias, these holes are not drilled through the PCB but are only accessible from one side. Forming these vias involves drilling through the PCB and filling the holes with a conductive material.
Several methods can be used to drill the vias, including mechanical drilling, laser drilling, and chemical etching.
Mechanical drilling involves using a physical tool, such as a drill bit, to create holes in the PCB. This method is typically used for larger vias or when precise control is unnecessary.
Laser drilling involves using a focused beam of light to vaporize the material in the PCB, creating a small, precise hole. This method is typically used for smaller vias or when higher levels of accuracy are required.
Chemical etching involves immersing the PCB in a solution that etches away the material in the PCB, creating a hole. This method is typically used for larger vias or when precise control is unnecessary.
Once the vias have been drilled, they are filled with a conductive material. This can be done using electroplating, where a thin layer of conductive material is deposited onto the surface of the PCB.
The PCB is then heated to cure the conductive material and ensure proper adhesion. Other methods of filling the vias, such as conductive polymer filling, may also be used depending on the requirements of the PCB.
Overall, forming vias in a flexible PCB is critical in the via-in-pad fabrication process. Properly formed vias are essential for ensuring proper electrical conductivity and connection between different layers of the PCB.
Surface mount technology (SMT) is a way to make electronic circuits where the parts are attached to the surface of the printed circuit board (PCB) instead of being put into holes.
This technology has revolutionized the electronics industry, allowing smaller and more complex circuits to be produced at a lower cost.
In the SMT process, the components are placed onto the PCB using a pick-and-place machine, which is a machine that is specifically designed to position the components onto the PCB accurately.
The components are typically held in place using a sticky adhesive, keeping them in place while being soldered.
After the components have been placed onto the PCB, the next step is to solder them. This is typically done using a reflow oven, which uses heat to melt the solder, bonding the components to the PCB.
The reflow oven has a series of temperature zones that are carefully controlled to ensure that the solder is melted at the correct temperature and for the correct amount of time.
One of the main advantages of SMT is that it allows for smaller and more complex circuits to be produced; because the components are mounted directly onto the surface of the PCB, they do not need to be inserted into holes, which means that the PCB can be made much smaller.
This is particularly useful for applications where space is at a premium, such as smartphones or other portable electronic devices.
SMT is also faster and more efficient than traditional manufacturing methods. Because the components are placed onto the PCB using a machine, the process is much faster and more accurate than manual assembly. This results in a higher yield and lower production costs.
Overall, surface mount technology has significantly impacted the electronics industry, allowing smaller and more complex circuits to be produced at a lower cost and in less time.
It is an essential technology in the modern electronics industry and is used in various applications, from smartphones and laptops to medical devices and industrial equipment.
After the vias have been created and filled with a conductive material, it is important to clean the PCB to remove any residue from the etching and filling processes. This step is crucial for ensuring that the PCB is ready for testing and final inspection.
If any residue is left on the PCB, it can interfere with the connections and functionality of the vias, leading to performance issues.
Several methods can be used to clean the PCB, including manual, ultrasonic, and chemical cleaning. Manual cleaning involves using a soft cloth or brushes to remove any residue from the surface of the PCB gently.
Ultrasonic cleaning involves immersing the PCB in a solution and using ultrasonic waves to remove any particles or debris. Chemical cleaning involves using specialized cleaning agents to remove any residue from the PCB.
It is important to choose the appropriate cleaning method based on the specific needs of the PCB. For example, manual or ultrasonic cleaning may be more appropriate if the PCB has delicate components or good features.
If the PCB has stubborn residues that are difficult to remove, chemical cleaning may be necessary.
Regardless of the cleaning method chosen, it is important to follow proper procedures and take appropriate safety precautions to prevent damage to the PCB or harm to oneself.
This may include wearing protective equipment, such as gloves and eye protection, and following the manufacturer's instructions for the cleaning agents.
Cleaning the PCB is an important step in the blind, buried vias flexible PCB via the in-pad fabrication process. It helps to remove any residue from the etching and filling processes and ensures that the PCB is ready for testing and final inspection.
Choosing the appropriate cleaning method and following proper procedures and safety precautions are crucial for ensuring the integrity and performance of the PCB.
Testing the connections and functionality of the vias in a flexible printed circuit board (PCB) is an important step in the via-in-pad fabrication process.
This step helps to ensure that the vias are properly connected and functioning as intended, which is essential for the overall performance of the PCB.
Several methods can be used to test the connections and functionality of the vias, including visual inspection, electrical testing, and functional testing.
Visual inspection is a simple but effective method for checking the connections and functionality of the vias. This involves examining the PCB under a microscope or other magnifying device to look for any visible defects or issues with the vias.
This can include checking for proper alignment, ensuring that the vias are filled with conductive material, and looking for any signs of damage or defects.
Electrical testing involves using specialized equipment to test the electrical properties of the vias. This can include measuring the resistance of the vias, checking for continuity between different layers of the PCB, and verifying that the vias are properly connected to the circuits on the PCB.
This type of testing is typically done using automated testing equipment that can quickly and accurately measure the electrical properties of the vias.
Functional testing involves using the PCB in a real-world application to ensure it functions properly. This can include testing the PCB in a circuit or device or running software simulations to ensure the vias work correctly in different scenarios.
This type of testing can help to identify any issues with the vias that may not be visible during visual inspection or electrical testing.
Overall, testing the connections and functionality of the vias is an essential step in the blind, buried vias flexible PCB via the in-pad fabrication process.
By using a combination of visual inspection, electrical testing, and functional testing, manufacturers can ensure that the vias are properly connected and functioning as intended, which is essential for the overall performance and reliability of the PCB.
Semi-Flex PCBs are a cost-efficient solution to optimize a great number of projects. Made from FR4 material, which is the most affordable base material for PCBs, it can reduce space, weight, and improve the reliability of the final product as connectors are considered a reliability risk in many applications.
A semi-flex PCB is characterized by its ability to bend or flex to a certain degree while maintaining its structural integrity. This type of PCB is often used to save space in the final product and avoid the use of connectors between two circuit boards. Semi-flex PCBs are manufactured using a combination of traditional PCB fabrication processes, such as photolithography, etching, and drilling, as well as specialized techniques for handling the flexible substrate. The final product is a PCB that can bend or flex to a certain degree while maintaining its electrical performance and durability.
Hemeixin offers semi-flex circuit boards manufactured with conventional rigid FR-4 base materials. These boards are suited for one-time flex-to-install applications. The technology can be used for double-sided and multilayer boards. Because only standard materials and processing are used, this technology offers a low-cost alternative for applications with flexible or bendable areas in a printed circuit board (“PCB”). A semi-flex board most often replaces two PCBs and the required connectors and cables or allows a three-dimensional design and placement of the PCBs in a device.
The flexible segment in a semi-flex PCB is generated by controlled depth milling of the PCB in the required area. Hemeixin’s newest routing machines with z-Axis technology and integrated measuring and mapping functions is critical to the consistent and high-quality fabrication of semi-flex.
Often layout designers are reluctant to upgrade from a standard PCB with connectors to a notoriously expensive rigid-flexible printed circuit. The advantages are immense, but so are the costs and the layout requirements compared to standard PCBs. Many times this "jump" from standard technology to a high-tech segment is not necessary. Many printed circuits do not require dynamic bending capabilities in operation but only need to be fit into the housing neatly. This is called a "flex-to-install" requirement and here semi-flex offers a really cost-saving alternative technology.
A semi-flex PCB, can only be bent in certain areas that have been made to flex. As a result, the PCB will only bend in predetermined ways and at defined points. With the exception of the flex areas, a semi-flex PCB is stiff and more akin to a traditional rigid PCB. This is because semi-flex PCBs are manufactured using the manufacturing process ‘controlled depth routing’ or ‘milling’ down the FR4 material on the PCB until it is extremely thin and flexible. The flexible section is then treated to prevent cracking, allowing it to bend more or less freely. Semi-flex PCBs can also be manufactured by using thin core laminates. Laminates as thin as .005 mil. are utilized for static flex applications. RA (rolled annealed) copper foils is recommended to prevent cracking and allow for a more robust flex.
Semi-flex PCBs are well-suited to situations in which a PCB must be bent only for installation and projected future maintenance. Their flexible nature also makes semi-flex PCBs a good design choice for applications in which space is a major consideration. Semi-flex PCBs can be found in many common applications. Automobiles, industrial equipment and even safety electronics make extensive use of this circuit board category.
Hemeixin recommends a board or multi-board bar or frame to stabilize the bending area in assembly. The assembly process can be standard because no additional tempering, preparation, or handling is necessary. Installation of semi-flex circuits should be done with a bending tool to guarantee that the minimum bending radius is not violated.
To optimize transportation-safety and assembly, semi-flexible PCBs should always be produced in panels. You can easily seperate the prints from the panel after assembly and install the boards.
Material (reference) |
IT-158, Autolad1, SB170G, EM 825 |
Methodology |
Z-Axis Routing / ZAR |
Depth control routing tolerance |
+/-75 μm (3mil) |
Bending Layer |
1 or 2 |
Bending Cycle |
Max. 5 (depending on design) |
Bending Radius |
Min. 22T (T=the remaining thickness) |
Bending Area Width(BAW) |
Min. 0.02 θR (θ=Bending Angle) |
Cu thickness on bending layers |
HOZ,1 OZ, 2OZ, 3OZ |
Trace width and spacing on the bending layers |
Min. 0.2mm for HOZ, 0.25mm for 1OZ |
Glass type |
Fine glass e.g. 106, 1080 |
A minimum bending radius (R) needs to be taken into account because semi-flex is based on glass-reinforced rigid base material. The bending radius mainly depends on the ‘Remaining Thickness’ (RT) in the bend-area.
A guideline to calculate:
The minimum Radius (R): R = 22 * RT
The Bend Area Width (BAW) depends on the
Bending Angle (α) and Radius (R): BAW = (0.017 * α * R)
Example based on Remaining Thickness (RT) = 0.25mm;
R = 22 * 0.25 = 5.5mm
BAW = 0.017 * 90 * 5.5 = 8.4mm for 90˚ Bending Angle
BAW = 0.017 * 180 * 5.5 = 16.83mm for 180˚ Bending Angle
90° Bending Angle
180° Bending Angle
Before Bending
After Bending
Bevel :0,4 x 45°
PCB radius≥5MM
Side View
Top View
DESCRIPTION |
VALUE |
UNIT |
MARKED |
Minimum nominal thickness of bending area for one copper layer |
0.20 |
mm |
A |
Minimum nominal thickness of bending area for two copper layers (NOT Preferred) |
0.25 |
mm |
A |
Minimum flexible solder mask overlap onto solder mask |
0.50 |
mm |
B |
Minimum solder mask clearance from semi flex area |
0.15 |
mm |
C |
Minimum length of copper extending beyond the semi flex area (non functinal tracks) |
1.00 |
mm |
D |
Minimum rigid area copper clearance from semi flex area |
0.50 |
mm |
E |
Minimum microvia pad clearance from semi flex area |
0.50 |
mm |
F |
Minimum PTH pad clearance from semi flex area |
0.50 |
mm |
G |
Minimum NPTH clearance from semi flex area |
0.50 |
mm |
H |
Minimum component pads clearance from semi flex area |
1.00 |
mm |
I |
Minimum radii in the area of transition from rigid to semi flex area |
N/A |
mm |
J |
Minimum routing depth |
N/A |
mm |
K |
Minimum routing diameter |
N/A |
mm |
L |
Minimum track width (18μm) |
0.20 |
mm |
S |
Minimum track spacing (18μm) |
0.20 |
mm |
T |
Minimum track width (35μm) |
0.25 |
mm |
S |
Minimum track spacing (35μm) |
0.25 |
mm |
T |
Minimum track spacing to Semi Flex area side edge |
0.50 |
mm |
U |
A Semi-Flex circuit is made by thinning a portion of a rigid FR4 PCB down to 0.1~0.2mm making it bendable up to a certain point. Because it is a mono-material, made only from FR4, Semi-Flex is a cheap alternative to complex Polyimide Rigid-flex circuits. After populating, the semi-flex PCBs can be bent for the casing. It must be static use, not dynamic.
FR4 Semi-Flex is a cheaper solution than Rigid-Flex. It should not be used for applications exposed to shock and vibrations. FR4 Semi-Flex creates reliable 3D connectivity opportunities by replacing board-to-board connectors, which leads to space and weight reductions. It is widely used in Instrumentation, Metering, Sensor technology, and Industrial controls.
Green used to be thought of as the typical PCB colour. The availability of various PCB colours has increased with the development of technology and more inventiveness.
Every patched circuit is built on a printed circuit board or PCB for short. The PCB board is the most important and fundamental idea in electronics.
People frequently overlook making comments on this specific topic. But it's crucial to comprehend the fundamentals of PCB colour.
Understanding the fundamentals of PCB board and solder mask colours will be easier with this guide's aid.
The colour of the solder oil or solder mask depends on the colour of the PCB. It is made of lacquer that has been infused with colours recognised for hiding the traces of bare copper. The finished colour of the PCB, which is made of glass and epoxy, represents the solder mask. The protection of the circuit board from short-circuiting is one of the solder mask's primary uses.
For PCB boards, a variety of colours are available. A green solder mask is the common hue of printed circuit boards. However, the colour of PCBs is presently altering due to the introduction of many innovations and technological improvements. Most assemblers have been the driving force behind the rising use of PCBs in different colours instead of green in recent years.
The following are some justifications for selecting PCBs in colours other than green:
White, blue, black, yellow, red, and other colours are among the palettes used to create PCBs. PCB colour codes are a familiar name for PCB colours. Modern PCBs come in a variety of shapes and colours. For instance, green epoxy is still used in constructing PC motherboards.
The performance of the PCB is unaffected by the colour of the solder masks. However, the board resolution will change if various PCB colours are used. For instance, red and blue colours, which have substantially less resolution than yellow and black, can be used to match the resolution of a green PCB. The fact that solder masks with clear transparency typically have high resolution should be recognised.
Different varieties of solder mask colours have been seen. A solder mask made of cobalt and carbon is black. Due to the carbon content, this particular solder mask is conductive. Although conductive layers are generated over the PCB's lines, they can be employed as a shield to protect the signals from various types of outside noise.
Additionally pricey is a black solder mask manufactured from cobalt combination. In the majority of LED applications, white PCB colour codes are included. A blue solder mask will be seen, which is typically utilised in LCDs. It is employed to prevent any systemic distractions.
The red PCB colour code is typically used to distinguish the board from other boards. To identify any specific part included in group assembly, the red PCB colour code is primarily used. Precision equipment like oscilloscopes, analogue resources, and bench multi-meters frequently employ red solder masks.
Numerous sources have shown that printed circuit boards like the colour green over all others. It is a result of the green colour's superior performance compared to other PCB colours. When it comes to soldering the component pitch, green produces superior outcomes. The colour green is frequently thought of as the standard for printed circuit boards.
One of the top nations in the world for invention and cutting-edge technology engineering is Japan. It has been observed that Japan uses the largest percentage of green printed circuit boards. Germany, on the other hand, has reportedly used non-standard PCB colours more frequently than many other nations and engineering sectors.
There are various factors that must be taken into account if you decide to choose printed boards. One of them is selecting the PCB solder mask's colour. Although green is the most often utilised colour, other colours including yellow, white, and black are all accessible and don't come with any additional fees. The issue is deciding which colour should be used because there are several colours available for the PCB solder mask. Do picking colours other than green have any benefits or drawbacks? The brief information provided below will assist you in selecting a solder mask colour other than the conventional green hue:
Red: Red solder masks typically have a bold, businesslike appearance. There is good contrast between the planes, spaces, and traces.
The contrast is less than it is with the green printed circuit board. If there are any problems, the board traces are examined at any magnification. It should be noted that silkscreen, which removes the flux residues, is known to stand up strongly against red backgrounds. Although red appears appealing, striking, and bold, green is still regarded as the finest.
Blue: The solder mask PCB colour blue is similar to the Arduino blue hue. The contrast between planes, traces, and empty space is less than that between red and green printed circuit boards. Magnification is said to be necessary and required for evaluating manufacturing flaws when using blue solder mask colour.
However, it should be noted that the solder mask and silkscreen contrast is rather good, which is a benefit of utilising blue. Therefore, if you are utilising a board marked "heavy," blue may be the best option for you in this situation.
Keep in mind that blue looks to be a great option if you don't worry about revealing off-board traces and want to match the solder mask colour with your Arduino.
Black: The PCB colour black is difficult to work with. The contrast between open areas, planes, and traces is negligible compared to other solder mask colours. For the observation of this board, very strong magnification is necessary. It is a nightmare to inspect since a slanted angle is required to create a shadow to look for traces.
The heat absorption of the black PCB colour during reflow is another issue. The black solder mask requires significant cleaning effort since flux stains are more difficult to clear off the board and eventually need steps.
One benefit of using a black solder mask is that it complements the silkscreen's contrast effectively. The distinction between silkscreen and pads is generally acceptable. The separation is obvious without the use of lighting or optics. Only gloss black is offered for now. For PCB prototypes, a matte black solder mask colour still has to be created.
White: You haven't encountered white solder masks yet if you believe a black solder mask is the most difficult to handle. A white solder mask is not useful, according to experiments. The contrast in the white PCB colour is considerably lower than it is in black. Even turning it to the light when checking does not improve the visibility of its traces. The white printed circuit board is too difficult to clean since the indications are difficult to spot. However, the silkscreen contrasts in white solder masks are identical to those in a black hue, suggesting that they function extremely well. We do not advise using the white solder mask when other factors are taken into consideration.
Yellow: Why designers and engineers do not choose the yellow PCB colour is surprising. In the yellow solder mask, there is too much contrast between the voids, traces, and planes. It closely resembles green. Therefore, this dark and coppery-coloured yellow solder mask is the best option for you if your printed circuit board has excellent routing and is a true work of beauty.
You may use a black silkscreen with a yellow solder mask instead of the white one since the contrast is better. It has been shown to produce fantastic benefits for your design and work. You'll also see that there are no cleanliness issues with the yellow solder mask. Depending on its exceptional performance criteria, yellow should be taken into consideration with the hues green and red.
Therefore, this is all about various solder mask colours. You will feel more at ease selecting the ideal colour for your subsequent job.
Try new solder mask colours including PINK, ORANGE, GRAY and even TRANSPARENT.
In the world of industrial electronics, the heart of many systems lies in printed circuit boards (PCBs). These small but mighty components are responsible for ensuring everything runs like clockwork. Yet, like any technology, they can encounter their fair share of challenges. Understanding the common problems and best repair approaches can help keep your PCB-powered systems humming smoothly.
PCBs are delicate. Recognizing the types of defects that can arise over time and taking the necessary steps to identify them can help guarantee your components perform optimally. Here are some common problems to watch for:
Knowing the problems is only half the battle. Equally important is understanding how to address these issues. Here are some common repair techniques to approach PCB complications and restore equipment to full functionality:
The saying “prevention is better than cure” holds true for PCB woes. Avoiding issues is the gold standard. It starts with meticulous design and manufacturing practices, including:
When problems do arise, having a qualified repair technician at your side can be a game-changer. After all, in the intricate world of industrial electronics, every component matters.
]]>An acid trap is an area of a PCB that holds corrosive chemicals that should be washed away. Acid traps can be hard to detect, even for those experienced in PCBs. Many designers fall victim to them.
Defending against them isn’t a particularly difficult task, and it’s much easier to do than to fix the effects of acid corrosion. A little basic preparation and care can help your company keep designs free of acid traps and the damage they bring.
While the PCB manufacturer can usually help ensure the quality of the design before building it, it’s still much easier to fix any issues before it gets to that point. Review the circuit board’s layout carefully and look for acute angles and trace gaps that could create pockets for the acid to collect in. There shouldn’t be any places that could cause problems down the road.
The manufacturer will sometimes run a design through software that tests it for its manufacturability, so they know that the PCB’s layout won’t lead to problems. It may also help to identify PCB design issues that a DRC can’t catch. Your company can also perform this step if you want to be more prepared.
If you see an area that may become an acid trap, consider adding a via or two in that spot. These holes allow the acid to flow to the other side of the board, avoiding damage to traces or components. Of course, this requires caution, so you don’t drill through anything important on either side. Double-layered boards can be tricky in this regard, and this approach is best for single-sided boards.
Watch out for the hazards of group vias. When placing multiple vias close to traces, they can create pockets that become acid traps. Make sure that your design keeps gaps in between vias to space them further apart. They shouldn’t be close to each other or traces. The small amount of board real estate available in PCB design can make this spacing difficult. So increase the gaps if possible.
Using photoactivated etchants is one of the easiest and simplest ways to avoid acid traps, and most PCB manufacturers are jumping on this route. It eliminates many of the hazards of acid traps. Traditional etching chemicals include:
The modern approach of using photosensitive films offers many benefits over their predecessors. Though you still need to abide by the PCB etching process, you can minimize the impact of overaggressive chemicals by using the photosensitive approach. Most PCB manufacturers now use more modern procedures that eliminate the use of corrosive materials like ferric chloride and hydrochloric acid. When you use these chemicals, there may be a higher chance of the acid seeping into unwanted areas and corroding more copper. Eliminating these chemicals all together is a great way to avoid their destructive effects.
Photoactivated etchants are those that activate or harden underneath a UV light. They aren’t very reactive unless exposed to the right type of lighting. If the etchant is in a blocked-off area of the board, the lack of light prevents it from causing too much damage. Even thicker layers of copper perform well with photoactivated etchants. They offer cleaner edges and can, therefore, help reduce acid collection in certain areas. These etchants also tend to be less corrosive, so if they become trapped in corners and pockets, they won’t affect the copper as much as traditional chemicals. This method is the one commonly used today as it tends to offer better results.
Working with a fabricator that uses photosensitive films is one of the most significant ways to reduce the risk of acid traps. This chemical aggressiveness is more of an issue for DIY PCB builders, but businesses that operate on larger scales shouldn’t have a problem finding manufacturers that work with modern materials.
This step may seem like a no-brainer, but running DRC before submitting a design is a critical step. This software will help you identify issues present on your board. It analyzes your layout against a set of defined parameters to see whether or not the board has those parameters in place. For instance, you can use DRC to check that your trace lines meet a specified width and whether circuits have separate grounds. You can also use it to check that all your angles are properly sized, and there aren’t any small gaps. The DRC step is especially vital if your board is high-density or has multiple layers.
Design for manufacturing (DFM) software is an excellent way to check your board for its manufacturability. It improves the ease and efficiency of the manufacturing process, and that includes how it is going to stand up to the etching process. Acid traps, after all, occur during manufacturing. It can also help optimize a board in terms of dimensions and materials, making life a little easier for everyone involved. Running a design through a DFM program can help identify acid trap issues before they cause problems.
Another manufacturing consideration involves the modernity of your manufacturer’s process. Using photosensitive chemicals is one indicator of their practices. Learn about their manufacturing technique and assess whether it works for your needs. PCB design has come a long way, so make sure your manufacturer has kept up with the times.
Even running DRC can’t catch everything. Plus, human errors are common. Like spellcheck, you can’t depend on the DRC to find all errors in your work. Go over your design carefully, looking out for any of the pitfalls we’ve mentioned. It may be an extra step, but spending a little more time and effort here can offer significant savings in fixing errors and defective PCBs. It may even help to have another designer take a look to get a second pair of eyes.
Catching acid traps before your board reaches the manufacturing stage is crucial to minimizing wasted operational costs and getting boards printed on schedule. If circuit boards get printed with acid traps in place, you end up with a bunch of defective boards. Taking steps to eliminate acid traps before they reach manufacturing can save you a lot of headaches down the road and make the process smoother for both your company and the manufacturer.
]]>
White film refers to white solder mask, also known as white cover film, similar to white ink on a hard board, serving the purpose of solder mask insulation and circuit protection.
The material of the cover film is the same as the raw material of FPC, which is PI (polyimide), and it can also be flexed. Currently, there are two main processes for white FPC on the market: white film and white solder mask ink. White solder mask ink has a low cost, but due to its characteristics and process properties, it cannot be flexed or has poor flexing performance. On the other hand, white film has good flexing performance, high reflectivity, and higher pressure resistance characteristics.
The reflectivity of the white film can reach over 85%, and it has excellent flexing performance, with thicknesses of 40.5um and 68um, as follows:
1. Yellow Film: This material has a certain degree of transparency and features easy processing, low cost, and stable performance. It is suitable for most products, such as various types of ribbon cable products.
2. Black Film: It is less prone to discoloration, has a high-end appearance, does not reflect light, and offers better confidentiality for circuits. It is commonly used in high-end or light-absorbing products like automobiles, phones, LED displays, etc.
3. White Film: White film has an additional white coating layer, slightly thicker than yellow and black films. Due to the reflective properties of the white coating, laser shaping may be somewhat more challenging. It is often used in products that require reflection, such as lighting fixtures, LED displays, medical beauty products, etc.
Features of FPC White Film: Flexibility, high reflectivity, high-temperature resistance, uses a non-adhesive substrate, can be bonded with 3M adhesive, and can be used for SMT.
Surface wetting of SMT chip proofing refers to a phenomenon when the solder spreads and covers the surface of the metal to be soldered during soldering. The surface wetting of SMT chip processing generally occurs in the case of close contact between the liquid solder and the surface of the metal to be soldered, and only the close contact has sufficient attraction.
When there are contaminants on the surface of the corresponding welded metal, it must not be in close contact. In the absence of contaminants, when the solid material contacts the liquid material in the SMT patch proofing, once an interface is formed, the surface will be reduced. The adsorption phenomenon of energy, the liquid material will spread out on the surface of the solid material, and this is the wetting phenomenon. In the dipping test, the following phenomena are present on the surface of the pattern taken out of the molten solder bath:
1. Partial wetting Some areas of the welded surface are wetted, and some are not wetted.
2. The non-wetting surface is restored to its original appearance, and the welded surface remains the same as before.
3. After wetting and removing the molten solder, the soldered surface will retain a layer of uniform, smooth, crack-free, and well-adhered solder.
4. Weak wetting: The soldered metal surface of the SMT patch proofing is wetted at the beginning, but after a period of time, the solder will shrink from part of the soldered surface to droplets and finally leave only a thin layer of solder in the weakly wetted area .
FINEST provides a one-stop PCBA manufacturer platform, SMT patch, PCB proofing, DIP welding processing, PCB board making, a full set of electronic components purchasing, and some purchasing one-stop PCBA manufacturing services.
]]>
What is additive manufacturing?
The additive manufacturing is very important for rapid mockup in 3D printing technology. It is a smart technology that allows forming the physical components from the 3D computer models. It can build the component layer by layer until the final product is ready. This process is very easy to shorten the product development cycle. You can also get some rapid mockup design that will help you to create a graphic layout and an outstanding look. It is far more different from traditional manufacturing and painting.
Different types of 3D printing:
Here are so many types of 3D painting varieties. These are such as follows:
1. SLA- Stereolithography: It is one of the oldest additive printing technologies. This form of 3D printing works like a layer of photosensitive liquid resin. This SLA printing can bake in a UV light in order to complete the whole curing process. DLP is as similar to SLA. You can get the high-quality surface finishing in this printing technology. You will get the smooth and ideal surface for the products. You will get high quality and intricate design as well.
2. FDM- Fused Deposition Modeling: It is one kind of common form of 3D printing in the consumer market. This particular form of 3D printing is a cost-effective way for everyone. It is perfect for the individual and small business organization. It is the fast and advanced process for engineering and designing department. It is recognized as the most cost effective way to produce customized thermo-plastic parts. Now the rapid mockup can also help you to get an acute finishing.
3. SLS- Selective Laser Sintering: This process is a process to solidify and bond the grains in the case of plastic, ceramic and glass materials. It can also applicable for metal materials. This works like an additive manufacturing process. It provides the printing by giving layer after layer. The main benefit of SLS is that it does not need any kinds of supportive structure in order to produce intricate designs.
Apart from these, there are many different types of 3D printing. These are such as Powder Bed Fusion, Material Jetting, Binder Jetting and Sheet Lamination as well.
There are so many rapid mockup designing formulas that will enhance the look of the product or material.
Enjoy the benefits of 3D mockup:
You can simply have fun with the facilities of 3D mockup. You can experience these benefits. These are such as follows:
Change the background image: In this technology of advanced design, you can change the background image as per your choice. You can choose it from your library and personal computer as well.
Select your product: You can pick one of the four products in order to view its 3D rendering effect. You can choose anything from the list. You can see the 3D effect as well.
Change image on the product: You can select an image to be placed on your 3D product. You can choose it from your computer as well. You can try it out and see how it fits in real image.
Change the colour of the product: You can choose the colour from the selector. You can see the change and how the product will look in the real life.
360-degree view: You can also see the 360-degree view of your product. You can rotate and view the product in 360-degree view in order to get a clean and clear perspective.
Saving the photo: You can also take a snapshot of your 3D rapid mockup from different angles. You can also save it on your PC for later review.
This procedure of 3D printing is always changing and evolutionary process. It allows and applies innovative techniques to your advertisement technology. It will change the 3D printing knowledge. The new and advanced techniques can create a better solution. You can also buy some tools in order to get the finished look. The 3D printing solution can give you an advanced and alluring look. You can get the best look through the rapid mockup solution.
]]>The movement of the head of a component placement machine in the vertical place for parts orientation and insertion.
]]>The ratio of usable parts at the end of a manufacturing process to the number of components submitted for processing.
]]>Capillary absorption of liquid along the fibres of the base material.
A needle-shaped metallic growth on a printed circuit board.
The formation of a relatively uniform, smooth, unbroken and adherent film of solder to a base material.
A condition of base material in which a weave pattern of glass cloth is appearing on the surface though the unbroken fibres of the woven cloth are completely covered with resin.
The technique of joining parts to a PCB by passing the assembly over a wave of molten solder so as to coat the pre-fluxed areas to be joined.
A surface condition of base material in which the unbroken fibres of woven glass cloth are not completely covered by resin.
]]>A conductor or portion of a conductor layer on or in a printed board which is maintained at other than ground potential. It can also be used as a common voltage source, for heat sinking, or for shielding.
The absence of any substances in a localized area.
The property of a fluid that enables it to develop and maintain a level of shearing stress dependent upon the velocity of flow and then offer continued resistance to flow. The absolute unit of viscosity measurement is poise, or more commonly, centipoise.
A virtual (computer model) representation of an electronic product that can be used to explore different design scenarios and then verify that the product will work as planned before building a physical implementation.
A plated through-hole used as an interlayer connection and not as a terminating point for a component lead. It may also be blind (incomplete penetration) or buried (non-surfacing).
A plated through-hole whose only purpose is to connect a track on one layer or side of the board through to a track on another layer or side. In a via, there is no intention to insert a component lead or other reinforcing material.
The solder re-flow process that uses a vaporized solvent as the source for heating the solder beyond its melting point,creating the component-to-board solder joint.
A component handling tool with a small vacuum cup for ease of pick-up and removal during de-soldering.
]]>A hole containing no conductive material nor any other type of reinforcement.
A logotype authorized for placement on a product which has been recognized (accepted) by Underwriters Laboratories, Inc. (UL).
A groove or excavation at one edge of a conductor caused by etching.
Fluxless soldering wherein molten solder is vibrated at ultrasonic frequencies while making the joint.
Underwriter’s Laboratories, Inc., a corporation for the purpose of establishing safety standards on types of equipment or components in USA and Canada.
]]>The deformation of a rectangular sheet, panel or printed board, that occurs parallel to a diagonal across its surface in such a way that one of the comers of the sheet is not in the plane formed by the other three corners.
Lines which define the borders of a printed board.
Dielectric material with higher glass transition temperature and better thermal stability than epoxy resin, however, more expensive and not in common use.
A signal-carrying circuit composed of conductors and dielectric material with controlled electrical characteristics used for the transmission of high-frequency or narrow-pulse type signals.
Two or more transmission lines.
The metallic conductive strips that provide connections between components, terminals, etc., on printed circuits.
A single conductive path in a conductive pattern.
A soldering defect in which a chip component moves into a vertical position during solidification of the solder so that only one terminal is connected. It is caused by defective re-flow processing.
Also called fabrication hole, pilot hole, or manufacturing hole. These are used as PCB reference points upon which other dimensions are based.
The application of molten solder to a basis metal in order to increase its solderability.
An electrical connection between conductive patterns on opposite sides of an insulating base, e.g. plated through-hole or clinched jumber wire.
A plastic cured or hardened by heating into a permanent shape. Thermosets cannot be re-melted.
A plastic set into final shape by forcing the melted polymer into a cooled mould. The hardened form can be re-melted several times.
A device made of two dissimilar metals which, when heated, generate a voltage that is used to measure temperatures.
Special points of access to an electrical circuit, used for testing purposes.
A pattern used for inspection or testing purposes.
A device that adapts a specific assembly under test system via inter-connection.
A pattern as an integral part of the PCB on which electrical tests may be made to non-destructively evaluate process control. A portion of a circuit used exclusively to functionally test the circuit as a whole.
A printed board suitable for determining acceptability of the board or of a batch of boards produced with the same process so as to be representative of the production board.
(Turpentine)A solvent used in cleaning electrical assemblies.
The part of component that makes contact with a pad on a substrate.
A portion of a conductive pattern usually, but not exclusively, used for the connection and/or attachment of components.
A printed board fabrication method of covering over plated through-holes and the surrounding conductive pattern with a resist, usually dry film.
A via with solder mask completely covering both its pad and its plated through-hole. This completely insulates the via from foreign objects, thus protecting against accidental shorts, but it also renders the via unusable as a test point.
The depiction of the temperature that a selected point traverses as it passes through the re-flow process.
Du Pont trade name as an inventor for PTFE(Polytetrafluoroethylene).
Components attached to continuous tape for automatic assembly.
A packaging method of housing surface-mount parts in their own tape cavities in a long continuous strip. The cavities are covered so that the tape can be wound around a reel for convenient handling and machine set-up.
]]>A component lead wire that extends through a hole in a printed board and its lead extension is flattened(swaged)to secure the component to the board during manufacturing operations.
A chemical added to the cleaning solution to lower surface tension and to promote wetting.
The natural, inward, molecular attraction force that inhibits the spread of a liquid at its interface with a solid material.
The electrical connection of components to the surface of a conductive pattern that does not utilize component holes.
The passage of current over the boundary surface of an insulator as distinguished from passage through its volume.
A measure in ohms of an insulating material’s (as in FR-4) electrical resistance between conductors.
Test for the level of resistance of an insulating material, such as FR-4.between conducting members of a board (traces, contacts).
A hole in a printed board that has its inside surface plated or otherwise reinforced.
A process for obtaining conductive patterns by selective removal of unwanted areas of conductive foil from a metal clad base material.
See Base Material.
A type of transmission line configuration which consists of a single narrow conductor parallel and equidistant to two parallel ground planes.
The deformation resulting from a stress.
A component lead that extends through a hole and is terminated without subsequent forming.
A method by which successive exposures of a single image are made to produce a multiple-image production master.
The making of solder connections by sequentially using solder alloys with successively lower melting temperatures.
The use of statistical techniques to analyse the outputs of processes with the results guiding actions taken to adjust and/or maintain a state of quality control.
Wiring which is produced by die stamping and which is bonded to an insulating base.
See Cross-talk.
The highest temperature at which filler metal(Solder) is completely solid.
A method of connecting a solid wire to a square, rectangular, or V-shaped terminal by tightly wrapping the wire around the terminal with a special tool.
A process of joining metallic surfaces with solder, without the melting of the base metals.
The portion of a soldering iron that is used for the application of the heat that melts the solder.
The ability of a metal to be wetted by molten solder.
The evaluation of a metal to determine its ability to be wetted by solder.
The side of a printed board which is opposite to the component side.
An ink, lacquer, photo-resist or metal coating which is not wetted by molten solder. It is applied to specific areas of a PCB to stop them from being solder-coated, usually when mass soldering.
An undesirable protrusion of solder from a solidified solder joint or coating.
A core of solder in a plated through-hole.
Finely divided particles of solder, with additives to promote wetting and to control viscosity, tackiness, drying rate, etc.
Liquid formulations that are used in intermix wave soldering and as coverings on static and wave soldering pots in order to eliminate dross and to reduce surface tension during the soldering process.
Coating with mask and insulate areas of a circuit pattern where solder is not desired.
A screening defect characterized by prints having jagged edges, the result of incorrect moving pressure.
The process of immersing printed circuit boards into hot liquids. Often referred to as HASL or HAL (Hot Air Levelling).
A preferable concave surface of solder that is at the interconnection of the metal surfaces of a solder connection.
A small hole that penetrates from the surface of a solder connection to a void of indeterminate size within the solder connection (process indicator).
The unwanted formation of a conductive path of solder between conductors.
A metal alloy with a melting temperature that is below 450℃.
The period after pre-heat and before re-flow peak temperature where the internal temperature differences between parts allowed to equalize.
The return of a stencil to normal level after deflection by the pressure of the squeegee moving across the surface.
The space between the top surface of the substrate and the underside of the stencil when the squeegee is not in play.
Surface Mount Technology. Defines the entire body of processes and components which create printed circuit assemblies without components with leads that pierce the board.
Solder Mask Over Bare Copper.
Resin, smeared over the edge of an internal copper layer of a multi-layer board during drilling, which prevents the layer from making electrical contact with the barrel of the hole.
Surface Mounted Device. Any component or hardware element designed to be mounted to a printed circuit board (PCB) without penetrating the board.
A spreading of the solder paste after printing but before re-flow soldering. If excessive, a loss of definition may result.
A production master used in the process of making a single printed board.
A printed board with a conductive pattern on one side only.
The process of creating a virtual representation(a computer model)of an electronic component, circuit board, or system and applying virtual test signals to the model to verify its functionality and possibly its timing.
Often used for legend print and means the printed reference designators on a printed wiring boards.
An electrical impulse of a pre-determined voltage, current, polarity and pulse width.
A conductor layer intended to carry signals, rather than serve as a ground or other fixed voltage function.
An individual conductor used to transmit an impressed signal.
Short-circuit, An abnormal connection of relatively low resistance between two points of a circuit or conductors from different nets either touch or some closer than the minimum spacing allowed for the design rules being used.
A physical barrier, usually electrically conductive, designed to reduce the interaction of electric or magnetic fields upon devices, circuits or portions of circuits.
A condition occurring during etching in which the dielectric material, in intimate contact with the foil, is incompletely removed though acceptable etching may have been achieved elsewhere. In re-flow soldering, a condition in which component bodies block the infra-red energy from certain areas of the board. In wave soldering, the solder fails to wet some parts leads due to other devices blocking the flow of solder.
See Activating.
A technique involving the use of a solvent followed by hot-water rinses and drying.
A process for obtaining conductive patterns by a combination of electroless metal deposition with etching and/or electroplating. A semi-additive process is used in conjunction with a metal clad base material.
A network of metal or fabric standards mounted tautly on a frame and upon which the PCB’s circuit pattern is superimposed by photographic means.
A process for transferring an image to a surface by forcing suitable media through a stencil screen with a squeegee. Also called silk screening.
A drawing that shows, by means of graphic symbols, the electrical connections, components and functions of a specific electronic circuit arrangement.
An aqueous organic or inorganic base solution with additives that promote the removal of flux.
]]>A hard, natural resin (nowadays also synthetic),consisting of abietic and primaric acids and their isomers, some fatty acids and terpene hydrocarbons, that is extracted from pine trees and subsequently refined.
The mildest of solder fluxes and generally requiring added organic activating agents.
A printed pattern of non-conductive material by which the circuitry and components are delineated on a board to aid in service and repair of the board.
A connector which terminates conductors at the edge of a printed board, which bringing the terminations our at right angles to the plane of the board conductors.
A flat cable with round conductors.
Science of flow ,is the study of the flow and deformation of matter and is particularly important with regard to colloidal systems.
The act of repeating one or more manufacturing operations for the purpose of improving the yield of acceptable part.
A manufacturing step or process that is repeated to bring a non-performing or non-conforming component or circuit to a functional condition.
The film pattern on a printed circuit board enabling the exposure of conductive areas for subsequent plating.
Coating material used to mask or to protect selected areas of a pattern from the action of an etchant, solder, or plating. Also see Dry Film, Resists, Plating Resists and Solder Resists.
A high-molecular-weight organic material with no specific melting point. A polymer.
Resin transferred from the base material onto the surface or edge of conductive pattern normally caused by drilling. Sometimes called epoxy smear.
Any visual or measurable form of process-related contamination.
The ability of a system to return to a specific parameter, said of equipment when evaluating its consistency of processing.
The process of restoring the functional capability of a defective component or circuit.
The probability that a component, device or assembly will function properly for a defined period of time under the influence of specific environment and operational conditions.
The radio of the quantity of water vapour present in the air to the quantity which would saturate the air at the given temperature.
The alignment of a pad on one side of the printed circuit board or layers of a multi-layer board to its mating pad on the opposite side.
A symbol used as a reference point to maintain registration.
The melting of an electro-deposit followed by solidification.
The portion of the re-flow soldering process during which the temperature of the solder is raised to a value that is sufficient to cause the solder to melt.
Joining components to substrates by placing the parts into solder paste and then melting the paste to achieve re-flow and the interconnection.
The edge of cable or conductor from which measurements are made.
A lead extending out of the side of a component, rather than from the end.
]]>Printed Wiring Board; same as PCB.
See Bond Strength.
Plated through-holes. Plating the holes on their internal wall.
A 1 to 1 (1:1) scale pattern which is used to produce one or more printed boards (rigid or flexible) within the accuracy specified on the master drawing.
A detectable anomaly, other than a defect, that is reflective of material, equipment, process and/or workmanship variations.
Equipment for making electrical contact between the bare PCB, components or assemblies and the continuity tester. Probling devices range from manual units for low volumes to computer-controlled systems.
A conductive pattern within or bonded to the surface of a base material intended for point-to-point connection of separate components and not containing printed components.
A sketch that depicts the printed wiring substrate, the physical size and location of electronic and mechanical components, and the routing of conductors that electrically interconnect components, in sufficient details to allow the preparation of documentation and artwork.
See Printed Board.
A document that shows the printed board (rigid or flexible), the separately manufactured components which are to be added to the board, and any other information necessary to describe the joining of these parts to perform a specific function
A portion of conductive pattern formed by printing, serving as one part of a contact system.
A component part, such as an inductor, resistor, capacitor, or transmission line, which is formed as part of the conductive pattern of the printed board.
Circuit where the interconnections between components, terminals, sub-insulating board
A printed circuit board to which discrete components; hardware, and other electronic devices have been attached to form a complete operating unit.
The general term for completely processed printed circuit or printed wiring configuration. It includes signle, double, and multi-layer boards, both rigid and flexible.
A printed board with electrical or mechanical components, other printed boards, or a combination of there, attached to it with all manufacturing processes, soldering, coating, etc. Completed.
A coating applied before the application of an adhesive to improve the bond.
An electrical pin contact which can be pressed into a hold in a printed board to make immediate contact.
Sheet material consisting of the base material impregnated with a synthetic resin, such as epoxy or polymide, partially cured to the B-stage.
The process portion of the re-flow heat curve in which the PCB is heated from ambient at a pre-set rate and prior to full liquidus at the solder joint areas.
A resist which is decomposed (softened) by light and which, after exposure and development, is removed from those areas which were under the transparent parts of a production master.
An artwork, artwork master, or production master in which the intended conductive pattern is opaque to light, and the areas intended to be free from conductive material are transparent.
A printed board on to which all passive and active components have been assembled. Synonyms: printed board assembly (PBA), card, assembled board.
(kapton) Higher melting point plastic film used as base for flexible portions of flexi-rigid boards as well as for many flexible circuits.
High temperature thermoplastics used with glass to produce printed circuit laminates from multi-layer and other circuit applications requiring high temperature performance.
(mylar) low melting point plastic film used for cheap flexible circuits.
A technique of eliminating symmetry within a plane so that parts can be engaged in only one way in order to minimize the possibility of electrical and mechanical damage or malfunction.
A centimeter-gram-second unit of viscosity equal to that of a fluid requiring a shearing force of one dyne to move from a square centimeter area which a velocity of one centimeter per second (cps).
The practice of mechanically converting X - Y position information into a visual pattern, such as artwork.
A uniform coating of conductive metal upon the base material of the printed circuit board.
The process consisting of the electrochemical deposition of a conductive material on the base material (surface holes, etc.) after the base material has been made conductive.
Materials which, when deposited on conductive areas, prevent the plating of the covered areas. Resists are available both as screened-on materials and as dry-film photopolymer resists.
The temporary conductive path interconnecting areas of a printed board to be electroplated, usually located on the panel outside the borders of such a board.
A hole with the deposition of metal (usually copper) on its sides to provide electrical connections between internal or external conductive patterns.
Pertaining to Laminating. The finish present on the metallic surface of metal clad base material resulting from direct contact with the laminating press plates without modification by any subsequent finishing process.
Small holes or sharp edges on the surface of a solder joint generally caused by flux entrapment, oxidation or over-heating.
A depression in the conductive layer that does not penetrate entirely through it.
Chemically-induced fracturing or de-lamination on or below the surface of the base material; it is usually exhibited by a light area around holes, other etched areas or both.
Small imperfection which penetrate entirely through the conductor and/or solder.
A minute hole through a layer of pattern.
A terminal on a component. A component lead that is not readily formable without being damaged.
The quantity of pins on a printed board per unit area.
See Locating Hole.
Pin-in-hole a printed board assembly made up of components with leads which pass through holes in the board and lands. Synonyms: traditional assembly, conventional assembly.
A programmable machine usually with a robot arm for picking components from a feeder. It moves the part for placement and/or insertion to a specific site on the board.
A conductive board layer or artwork image representing a complete conductive layer.
A plotter that writes using light.
A polymer that changes characteristics when exposed to light of a specific frequency.
See Artwork Master.
A resist which is not removed after processing, e.g., plating resist used in the fully-additive process.
The force per unit width required to peel the conductor or foil from the base material.
Printed Electronic Component.
Printed Circuit Board.
The configuration of all conductive and/or non-conductive areas on a PCB. Letters and inscription may also be included. Pattern also denotes the circuit configuration on related tools, drawing and masters. Synonym: image
Selective plating of a conducive pattern.
A polymer resin (Polyparaxylense) that provides a thin, uniform coating on PCBs and components. It can be applied via vacuum for deposition on sharp edges and complex shapes.
The plating of the entire surface of a panel (including holes).
The base material containing one or more circuit patterns that passes successively through the production sequence and from which printed circuit boards are extracted. See Backplanes/Backpanels.
A portion of the conductive area of which components, terminals, traces, etc., are mechanically attached. (Also called land).
Quantity of functions (components, interconnection devices, mechanical devices) per unit volume, usually expressed in qualitative terms, such as high, medium, or low.
]]>Increase in printed circuit conductor width caused by plating build-up or by undercutting during etching.
The increase in conductor width at one side of a conductor, caused by plating build-up, over that delineated on the production master.
The gaseous emission from a laminate printed board or component when the board or the printed board assembly is exposed to heat or reduced air pressure or both.
Organic Solderable Preservative.
A water-soluble flux using organic acids as activators.
An area of a bare PCB which, due to over-etching or fabrication problems, separates two electrically connected points.
See Single-sided Board.
A test instrument measuring ionic residues on PCBs via the drop of resistivity over a specific time.
]]>Non plated though-hole.
A condition whereby a surface has contacted molten solder, but has had none of the solder adhere to it.
Material having electrical charges distributed over the surface of the molecule, thereby showing an electrical effect in solution.
A land on internal or external layers, not connected to the conductive pattern on its layer.
A configuration formed by functional non-conductive material of a printed circuit.
An epoxy resin with or without a filler, which may be added to improve thermal conductivity.
A process using specially formulated low-solid solder pastes whose residues require no cleaning.
A pin, lead or even junction which will have at least one wire connected to it.
Non-functional pad.
An alkaline chemical added to water to improve its ability to dissolve flux residues.
A net is a junction of component nodes. A netlist is a collection of nets that define all the connections in a circuit. It is obtained automatically from a schematic capture program.
A resist which is polymerized (hardened) by light and which, after exposure and development remains on the surface of a laminate in those areas which were under the transparent parts of a production ,master.
An artwork, artwork master, or production master in which the intended conductive pattern is transparent to light, and the areas to be free from conductive material are opaque.
The flared condition of copper on the inner conductor layers of a multi-layer board usually caused by hole drilling.
]]>A production master used in the process of making two or more printed boars simultaneously.
A portable test instrument which can be used to measure voltage, current and resistance.
Printed circuit boards consisting of three or more conducting circuit planes separated by insulating material and boned together with internal and external connections of the circuitry as required.
An enclosure that is located between the heating elements and the parts being processed that contains the atmosphere required for the re-flow soldering process.
A hole used for the mechanical mounting of a printed board or for the mechanical attachment of components to the printed board .
Also called back plane, or matrix board. A relatively large printed circuit board on which modules, connectors, sub-assemblies or other printed circuit boards are mounted and inter connections made by means of traces on the board.
A separable unit in a packaging scheme displaying regularity of dimensions.
A chemically inert substance added to a resin to change its properties.
A component mounting technology that uses both through-hole and surface-mounting technologies on the same packaging and interconnecting structure.
The lack of dimensional conformity between successively produced features or terns.
A defect which is not likely to reduce the usability of the unit for its intended purpose, It may be a departure from established standard having no significant bearing on the effective use or operation of the unit.
The minimum allowable distance between adjacent conductors that is sufficient to prevent dielectric breakdown, between the conductors at any given voltage.
One thousandth (0.001) of an inch. Not to be confused with Mil (short for millimetre).1Inch=25.4mm; 1mil=0.0254mm.
A type of transmission line configuration which consists of a conductor over a parallel ground plane, and separated by a dielectric.
A destructive test procedure in which a section of specimen it cut and removed for close examination.
A deposited or plated thin metallic film used for its protective or electrical properties.
Base material covered with metal on one or both of its sides.
The contour or shape of molten solder as formed by surface tension forces in turn controlled by wetting.
The temperature range over which the solder alloy melts .An alloy with a single melting point, rather than a melting range, is known as a eutectic alloy .
A metal electrode leadless face surface mount component that is round with metallic cap terminations.
A condition existing in the base laminate in the form of discrete white sports or crosses below the surface of the base laminate, reflecting a separation of fibres in the glass cloth at the weave intersection.
The statistical mean average time interval, usually in hours, that may be expected between failures of an operating unit. Results should be designated actual. Predicted or calculated.
Moulded Carrier Ring. A tape of fine-pitch chip package named for the method of supporting and protecting the leads. The leads are left straight; the ends of the leads are embedded in a strip of plastic, which is the Moulded Carrier Ring.
A hole size equal to the specified hole size before plating, plus the manufacturing tolerance, less twice the minimum plating thickness.
An accurately scaled pattern which is used to produce the printed circuit within the accuracy specified on the master drawing.
A document that shows the dimensional limits or grid locations applicable to any or all parts of a printed board(rigid or flexible),including the arrangement of conductive and non-conductive patterns or elements; size, type and location of holes.
A document showing dimensional limits and grid locations for all parts of an assembly to be fabricated. It includes the arrangement of conductors and non-conductive patterns and the size, type and location of holes.
Methods of soldering in which many joints are made in the same operation.
A material applied to enable selective etching, plating or the application of solder to a printed circuit board.
The distance between the reference edge of a flat cable and the nearest edge of the first conductor.(See also Edge Spacing)
The minimum metal width, at the narrowest point between the circumference of the hole and the outer circumference of the land. This measurement is made to the drilled hole on internal layers of multi-layer printed circuit board to the edge of the plating on outside layers of multi-layer boards and double-sided boards.
The orthogonal distance between two points.
A defect that could result in failure or significantly reduce the usability of the part for its intended purpose.
]]>A drawing that depicts the multi-state device implementation of logic functions with logic symbols and supplementary notations, showing details of signal flow and control, but not necessarily the point-to-point wiring.
A hole,notch or slot in the panel or printed board to enable it to be positioned accurately during manufacture and/or assembly. Synonyms: fabrication hole (or notch or slot),indexing hole, location hole, manufacturing hole, outrigger hole, tolling hole.
A physical feature in a panel or printed board used to position the board or mounted components accurately.
A mass re-flow soldering system test for the capacity repeatedly to process boards regardless of their volume though the oven.
The lowest temperature at which filler metal (solder) is completely liquid.
If a solder alloy with a long melting range is heated too slowly. the phase with the lowest melting point begins to flow first. The material left behind has a changed composition and a higher melting point and will not flow readily. An unsound and unsightly joint is the usual result of liquation.
See Conductor.
A land that has fully or partially separated (lifted)from the base material, whether or not any resin is lifted with land.
A format of lettering or symbols on the printed board, e.g. Part number, component locations, and patterns.
The distance that a component lead protrudes through the side of a board that is opposite from the one upon which the component is mounted.
See Component Hole.
(Pronounced “Leed”)-A terminal on a component.
Leadless ceramic chip carrier.
One in a series of levels in a board on which tracks are arranged to connect components. Vias connect tracks and zones between layers.
The thickness of dielectric material between adjacent layers of conductive circuitry in a multi-layer printed circuit board.
Light Amplified by Stimulated Emission of Radiation.
A plated through-hole without a land(s).
On a PCB, the conductive area(s) to which components are attached. Also called pad.
A combination of lands that is used to mount, interconnect and test a particular component.
The process of manufacturing a laminate; also the process used for application of a dry film photo-resist.
Multi-layer equipment that applies both pressure and heat to laminate and prepreg to make multi-layer boards.
Absence of laminate material in an area which normally contains laminate material.
Thickness of the metal clad base material, single- or double-sided, prior to any subsequent processing.
A product made by bonding together two or more layers of material.
]]>A slot used to assure the correct location in a mating connector.
A slot in a printed circuit board that polarizes it, thereby permitting it to be plugged into its mating receptacle with pins properly aligned, but preventing it from being reversed or plugged into any other receptacle.
A device designed to assure that the coupling of two components can occur in only one position.
Du Pont trade name for polyimide film.
]]>Minimization of inventory by supplying material and components to the production line directly before placement into the product.
An electrical connection between two points on a printed board added after the intended conductive pattern is formed.
The preferred surface mount lead form used on PLCCs, so named because the lead departs the package body near its Z-axis centre-line, is formed down the rolled under the package. Leads so formed are shaped like the letter “J”.
]]>The clearance around a pad, track, zone or via that defines the nearest approach allowed by conductors of another signal set.
The Institute for Interconnecting and Packaging Electronic Circuits, an American organization.
A plated through-hole connecting two or more conductor layers of a multilayer printed board but not extending fully through all the layers of base material comprising the board.
A conductive pattern which is contained entirely within a multi-layer printed board.
An electrical connection between conductive patterns in different layers of a multi-layer printed board. (See also Through Connection.)
See Through Connection.
The electrical resistance of the insulating material (determined under specified conditions) between any pair of contacts, conductors, or grounding device in various combinations.
The electrical resistance of the insulating material (determined under specified conditions) as measured between any pair of contacts or conductors.
A positive or negative transparency made from the production master and used as an inspection aid.
A collection of units of products bearing identification and treated as a unique entity from,which a sample is to be drawn and inspected to determine conformance with the acceptability criteria.
Assemblies of a specific production run selected for inspection or test as a sample of the entire run.
see "activating".
INDEX EDGE MARKER, INDEXING HOLE, INDEXING NOTCH, INDEXING SLOT: See Locating Edge, Location Edge Marker,etc.
A foreign particle in the conductive layer, plating, or base material.
A check of specific components(s) or cuicuits(s) within an assembly without their de-coupling from the primary circuit.
The resistance of a parallel conductor structure to the flow of alternating current (ac), usually applied to high-speed circuits and normally consisting of a constant value over a wide range of frequencies.
The chemical deposition of a thin metallic coating over certain basis metals that is achieved by a partial displacement of the basis metal.
See “Pit”
Integrated Circuit.
]]>The ability of a material to absorb and retain moisture from the air.
The section of a re-flow oven held at maximum temperature. Other zones include per-heat and cooling.
A void in the metallic deposit of a plated through-hole exposing the base material.
The force necessary to rupture a plated through-hole when loaded or pulled in the direction of the axis of the hole.
The arrangement of all holes in a printed board.
The dimensional location of the centre of a hole.
The quantity of holes in a printed circuit board per unit area.
A condition in which a hole is not completely surrounded by the land.
Wherein the assembly or component undergoes a high potential (ac) current.
The part of a lead adjacent to a termination that has been deformed by the edge of the bonding tool.
Any device that absorbs and draws off heat from a hot object, radiating it into the surrounding atmosphere.
A de-soldering method using a device that grasps, heats and pulls the leads to be removed.
Hot Air Solder Level (See Solder Leveling)
Induced fracturing or de-lamination on or below the surface of the base material, it is usually exhibited by a light area around holes, other machined areas, or both.
A polyester resin modified with halogens to reduce flammability.
Compounds containing fluorine, chlorine, bromine or iodine, which may be part of the activators in the flux system and must be cleaned.
High Density Interconnect.
]]>A surface mounted device lead which flares outward from the device body.
A technique for volume production of PCBs based on incoming inspection to catch the majority of device failures and inspection prior to populating, that will eliminate most manufacturing errors.
Removed portions of a ground plane that serves to isolate it form a hole in the base material to which the plane is attached
A conductor layer, or portion of a conductor layer, used as a common reference point for circuit returns, shielding, or heat sinking. All those areas, not consumed by traces or pads, of the PCB which are left unetched and tied to the ground on the board.
An orthogonal network of two sets of parallel, equidistant lines used for locating points on a printed circuit board.
Procedure to yield only pass or fail.
A coating process in which a set portion of resin is dispensed on the top of a chip or board. After spreading over the entire surface ,it is cured to form a soild protective coating.
A material used to fabricate printed circuit boards. The base material (fibre-glass) is impregnated with an epoxy filler which then must have copper laminated to its outer surface to form the material required to manufacture printed circuit board.
Laminate made from woven glass fibre material impregnated with polyimide resin.
Vector-based language, developed by Gerber Scientific Instrument Company, for sending commands to photoplotters.
A flowing inert gas atmosphere used to keep metal from oxidizing.
]]>A metallic coating, usually tin or solder alluvia, which has been melted and solidified forming a metallurgical bond to the base material.
To check an assembly using equipment that tests for the functions intended and engaging inputs and outputs.
An additive process wherein the entire thickness of electrically isolated conductors is built-up by copper.
Flame retardent laminate made from woven glass fibre material impregnated with epoxy resin.
Convection, consisting of flow, rate, velocity and temperature, as heat transfer of fluid or gas over solder joints to be re-flowed.
(See also Land Pattern).A set of properly sized and placed pads of a PCB on which a surface mounted component can be placed and soldered. Alternatively, the footprint is the board area occupied by a surface mounted component and its mounting pads.
A thin sheet of metal, usually copper, used as the conductor for printed circuits.
A wire of solder that contains one or more continuous flux-filled cavities along its length.
A mixture of rosin and small amounts of organic-halide or organic-acid activator, which improves the ability of a flux to remove surface oxides from the surfaces being joined.
A flux-related contaminant that is present on or near the surface after soldering and, if possible, should be washed away.
A substance used to promote or facilitate fusion, such as a material used to remove oxides from surfaces to be joined by soldering welding.
A conductor whose outer surface is in the same plane as the surface of the insulating material adjacent to the conductor.
An organic compound having fluorine atoms in its structure to lend chemical and thermal stability to plastics.
Also called wave soldering. A method of soldering printed circuit boards by moving them over a flowing wave of molten solder in a solder bath.
A device on a screen printer that drags solder paste back to the starting point after the squeegee has made a stroke. The return is for set-up of the next stroke as it does no printing on the backstroke.
A conductor failure due to repeated flexing which is indicated by an increase of resistance to a specified value for a specified time.
A random arrangement of printed wiring utilizing flexible base material with or without flexible cover layers.
A cable with two or more parallel, round or flat, conductors in the same plane encapsulated by an insulating material.
A device that enables interfacing a printed circuit board with a spring-contact probe test pattern.
The per centage of finished assemblies to pass all tests without re-work.
A gold-plated terminal of a card-edge connector.
Printed circuit design permitting two, and nowadays even three, traces between adjacent dip Pins. It entails the use of photo-imageable solder mask (PISM).
The concave formation of soldified solder between the land or pad and the component lead.
A mark both in the artwork and etched with the circuit traces of the PCB. It is used to identify artwork orientation on the board. Global fiducials locate the overall pattern; local fiducials pinpoint component sites, typically fine-pitch.
Flashscan Image Control Software: A DOS Program which sends Gerber files to the plotter.
A condition in which broken reinforcing fibres of the base material are exposed and protrude in machined or abraded areas.
A plated through-hole in a printed circuit board that is used to provide electrical connection between a trace on one side of the printed circuit board to a trace on the other side. Since it is not used to mount component leads, it is generally a small hole and pad diameter.
A listing of shorts and opens on a PCB to be repaired.
]]>A hollow tube inserted in a terminal or printed board to provide mechanical support for component leads or electrical connection.
Unwanted copper remaining on the base material after chemical processing.
The characteristic curve of a resin during cure showing reaction of temperature vs. time.
Removal of metal from the surface of PCB by chemical dissolution. The process is normally carried out selectively by masking areas of metal which are to be left on the PCB.
A board having a conductive pattern formed by the chemical removal of unwanted portions of the conductive foil.
The controlled removal of all resins of base material on the side wall of holes in order to expose internal conductor areas.
A solution used to remove, by chemical reaction, the unwanted portion of material from a printed board.
An organic ink, lacquer, photo-resist, self-adhesive plastic tape, metal deposit or other material which will prevent specific areas of the metal on a panel from being attacked by an etchant.
The ratio of the depth of etch (conductor thickness) to the amount of lateral etch (undercut).
Electro-Static-Discharge, the sudden transfer or discharge of electricity from one object to another.
(ESD susceptibility) The device’s ability to dissipate the energy of the discharge or withstand the current levels involved.
The percentage of defects not defected vs. the total inspected.
Electrical Rule Check: checks the integrity of a circuit (SCH) so that problems like open inputs, shorted outputs and much more are recognized.
Epoxy Resin Bonded Glass Fibre (See FR4).
Epoxy resins which has been deposited onto the surface or edges of the conductive pattern during drilling. Also called resin smear.
Materials that form straight chain thermoplastic and thermosetting resins having good mechanical properties and dimensional stability.
The damaging admission and trapping of air, flux and fumes; it is caused by contamination and plating.
The side of the film on which the photographic image is defined.
A discrete component that is fabricated as an integral part of a printed board.
The electrodeposition of a metal coating on a conductive object. The object to be plated is placed in an electrolyte and connected to the relative terminal of a dc voltage source. The metal to be deposited is similarly immersed and connected to the positive terminal. Ions of the metal provide transfer to metal as they make up the current flow between the electrodes.
Terminations made by heating with a stream of electrons in a vacuum.
The deposition of conductive material from an auto-catalytic plating solution without application of electrical current.
A layer of copper plated on to an insulating or conductive surface of a PCB by chemical reduction, that is, without the use of applied electrical current.
A series of contacts printed on or near any edge of a printed board and intended for mating with an edge-board connector.
The distance of a pattern, components, or both, from the edges of the printed board and intended for mating with an edge-board connector.
A connector (can be gold-plated edge contacts or a series of parallel lines of holes).
The distance of a pattern, components, or both, from the edges of the printed circuit board.
]]>