Tag Archives: Printed Circuit Board

Advantages of A HDI Printed Circuit Board and Its Applications

Unlike a traditional PCB, HDI has high-density circuitry. It consists of different types of vias, including buried, blind, and micro-vias. Some other features of this PCB include:

  • Surface to surface through vias
  • HDI construction involves layer pairs
  • Passive layers without electrical connection
  • Minimum two layers having through vias

HDI PCBs are ideal for smart devices or electronics having less weight. You must hire an experienced manufacturer to have an HDI printed circuit board because it has very narrow tolerances. So, only experts can handle such a PCB, as a little defect can lead to serious issues.

What are the benefits of an HDI circuit board?

There are many advantages of the HDI printed circuit board, provided it is according to the design parameters. Your product can perform better with the HDI technology. Let’s study its benefits one by one.

It Needs Less Space

HDI circuit boards don’t take much space, so the overall weight of the final product is also less. You can have more components on a board’s both sides, getting a functional, small, and lighter device.

Better Electrical Function

You get an enhanced electrical performance through HDI because of a little distance between the components and more transistors. Such features involve less power consumption, resulting in better signals. The signal transmission becomes fast due to a smaller size, besides, there are lesser crossing delays and signal losses.

More Cost-Effective

Since an HDI PC Board is smaller than traditional boards, it needs fewer raw materials, hence its cost is also less. Instead of having multiple PCBs in one product, a single HDI PCB is enough for better performance through small size and minimum material.

Quick Production

The production time is also faster than the conventional boards. Your product gets ready for selling if its construction involves an HDI printed circuit board having minimum materials. It is easy to place the components on HDI boards, moreover, better electrical performance is there to reduce the troubleshooting and testing time.

More Reliable

The micro vias in the HDI PCB come up with small aspect ratios and involve high-quality manufacturing, making the board reliable. A reliable PCB is always cost-effective, so the end product is also reliable and satisfactory

What To Consider While Designing An HDI PCB

You have to consider certain factors and parameters while designing the HDI circuit board. The production of such a board is different from others that we will discuss below.

Lamination Process

High-density PC Board Fabrication involves sequential laminations where you have to combine the PCB layers or cores with copper and pre-set layers. It involves heat and pressure according to the type of the circuit board. Once the lamination is over, you need to drill vias several times, unlike a traditional PCB. So, such a sequential lamination process helps manufacturers have flawless drilling without any breaking or shifting.

Understanding The Via-In-Pad

The construction of the high-density PCB involves the via-in-pad process to help you to make vias on a flat surface of your PCB. You have to plate vias, filling them in different ways, capping them, and then plating over them. The process of via-in-pad consists of 10 to 12 steps, and it needs skilled workers and special tools. There are many benefits of using the via-in-pad for HDI boards, including reduced space, simple thermal management, and less time to bypass the capacitors, in the case of high-frequency layout designs.

Considering Via Fills

You should also consider the type of via fill as it has to be compatible with the PCB requirements and its application. Some common filling materials, in this case, include electrochemical plating, copper, silver, and conductive and non-conductive epoxy of which non-conductive epoxy is highly used. Moreover, via fill should be flushed with the flat surface of the PCB and should also be fully soldered.

The via fill helps develop the blind, buried, and drilled vias in the case of both standard and micro vias. Then comes via plating to hide it under the SMT surface. It involves several drill cycles at balanced depths to have precise drilling. Such well-controlled drilling needs special tools and more time.

Layout Options

You will see the HDI circuit boards having different layout designs, including

  • 1-n-1 PCB
  • 2-n-2 PCB

A 1-n-1 PCB is the simplest HDI circuit board as it is a single construction of multiple layers of high density. These layers are interconnected, and such a board needs sequential lamination on both sides of the core. Whereas the 2-n-2 PCB consists of two layers of high density to help you to stack micro vias around the layers. The micro vias have copper filling in the case of complex layout designs.

The HDI structure can reach high levels of X-n-X even though its complexity and cost limit the construction. There is also the any-layer HDI with a very dense layout where conductors can interconnect easily through laser micro vias. You will see such designs in CPU and GPU chips, like in many mobile devices and smartphones

Laser Drilling

When it comes to the any-layer HDI, you will have to apply the laser drills to create micro vias. In this process, the drill emits a laser of 20 microbe diameter which can easily cut the glass or metal, providing small and clean vias. You can also use the uniform glass to make very small holes, as such a glass type has a low dielectric constant.


Cost of High-Density PCBs

Various factors can affect the cost of an HDI PCB, making it high or low. Here, we will discuss certain things to help you have a budget-friendly circuit board.

1-Quantity and Type Of Vias

Whether you choose a through-hole or micro vias, it will affect the cost of the board. Likewise, the number of holes also influences the cost. Larger vias will cost you less than smaller vias, as smaller ones are hard to create with precision.

2-Layers And Stack Up Height

The number of layers also affects the PCB cost. Likewise, you have to consider the height of the stack up to determine your budget. According to engineers, the 2-n-2 high-density circuit board’s design is more complex than the 1-n-1, so it costs you more. Moreover, extra layers also increase the PCB cost, so design your board carefully with a suitable number of layers.

3-HDI PCB Materials

The material you choose for your PCB also determines its cost. Some common core or base materials, in this case, include metal, fiberglass, FR4, etc. Whereas the finishing materials can be ENIG, immersion tin, HASL, gold, immersion silver, and many others.  Most manufacturers use the ENIG as it is smooth and easy to solder. You also have to consider the application of the board while choosing its material.

4-Quantity Of Sequential Layers

The number or quantity of the sequential lamination also affects the cost. The number of holes and the number of layers help determine the number of sequential laminations needed for HDI. Though more lamination means high cost and construction time, it ensures a reliable product that performs faster.

5-Type Of Setup

The type of setup also affects the PCB cost, like it is either stacked or staggered.  You can fill the stacked vias with copper, but it is not so with staggered vias. Via filling means you need additional materials and more time to produce your product or device.

6-Size of the Pad

You can decrease the cost by considering the pad size in the early stages. The HDI PCB design will be cost-effective if you choose the pad size wisely.

7-Less Turnaround Time

If you need your HDI board urgently, it would also increase its overall cost. An urgent order is always costly, so plan your project to avoid urgent construction and have a cost-effective project.

8-PCB Manufacturer

The PCB supplier or manufacturer should have competitive prices, or it will become costly for you. The supplier should offer a high-quality product at an affordable cost. Poor quality can end up in multiple repairs in the future, so select your HDI supplier wisely.

Applications of HDI PCB

HDI printed circuit boards are getting popular these days because of smart devices. High-density boards are not only cost-effective but they ensure high performance and reliable products.

  • The HDI PCBs are used in multiple industries, including consumer electronics, such as smartwatches, smartphones, tablets, laptops, digital cameras, as well as many GPS devices. The high-density circuit boards are also essential for IoT devices that you need at homes, such as refrigerators and smart thermostats. All such devices have made HDI technology more in demand.
  • HDI PCBs are also used in communication equipment that runs smart devices, such as routers, semiconductors, switches, and modules. Where there are radio waves in a gadget, means it has an HDI PCB. You will also see such circuit boards in digital audio and video equipment. From personal to network devices, all digital products come up with HDI PCBs.
  • Another application of the HDI board is in the automotive industry. Likewise, you will see it in aerospace where devices and equipment have to be lightweight to perform better. The latest cars also come up with computerized equipment. Like, you will see cars with boards having 50 microprocessors to handle engines, diagnostics, and safety features.
  • Similarly, the onboard Wi-Fi, GPS, backup sensors, and review cameras also depend on HDI printed circuit boards. HDI technology is constantly growing with the advanced automotive industry.
  • These days, you will see advanced medical equipment and devices which also depend on HDI circuit boards. Such equipment is used for monitoring, scanning, x-ray, and lab tests. The high-density PCBs make medical devices more reliable, functional, and cost-effective. Doctors can get reliable test results for their patients with advanced equipment.

Hence, you can’t imagine advanced gadgets, devices, and equipment without HDI PCBs due to their smart components. Would like to know more about HDI PCBs or printed circuit board assembly? Email us at sales@pnconline.com


Printed Circuit Board Copper Thickness Vs Current

The right function of PCB depends on the copper thickness, trace width, and weight. Printed circuit boards have traces made of copper, and we also call them conductors. Copper traces have a specific thickness, width, length, and weight that affect the flow of current.

PCB has copper layers for the flow of electric current. The wrong copper thickness can affect the PCB assembly process. But, if you understand the relationship between copper thickness and signal transmission, as well as the cost of PCB fabrication, it would help you choose the right copper weight or thickness for PCB design.

So, you must know what is copper thickness or weight and why is it important. You should also know the heavy copper’s application, and PCB construction cost.

Sometimes you can’t change the trace width due to certain spacing requirements or PCB density. But, you can change the copper thickness to have maximum current flow. You have to consider signal integrity while designing a PCB. The signal integrity and current loss rely on the amount of impedance that happens on copper traces.

Printed circuit boards with heavy copper are used in high-power electronic devices which are vulnerable to tough environments. Thick traces ensure durability and can carry more current without increasing the trace width or length. However, lighter copper traces are also used to have a certain trace impedance without having a highly small trace width or length.

You must understand the relationship between the current flow and copper thickness while designing your PCB. So, you have to know the copper trace fabrication, in this case, and its effect on signal integrity.

PC Board Fabrication

PCB fabrication involves different steps, including etching which is done on the inner layers and the top surface of the board. You need a laminate sheet finished in copper. In etching, you have to remove additional copper from traces and several other parts of the PCB, like pads and angular rings. Fabricators use an ammonia-based liquid to complete the process of etching.

Generally, the copper sheet thickness is 1oz, like 0.5 oz. on each side of the sheet. You can etch it down to decrease the thickness or can increase the thickness by plating it up to have the desired sheet.

The sheets are done rough during fabrication to bond them to the dielectric material. However, the roughness can also affect the signal integrity in the case of high-frequency boards. The frequency above 100MHz can result in trace resistance that opposes the flow of current.

In the case of plated vias, you should add traces after drilling the holes and it often involves the process of electrodeposition. For example, the PC Board manufacturer places the circuit board in an electrolytic solution having copper ions. Then, he applies a direct current to create a potential around the hole, distributing the ions in the entire via, which is also known as filling. Such a distribution helps you to find the quality of the signal flow that occurs along traces. So, it is very useful to understand PCB fabrication to have a functional design.

Relationship Between Copper Thickness And Signal Flow

In general, fabricators buy copper sheets with specific weight and thickness as they want fixed numbers. But, engineers say that the copper parameters are changeable after having a set trace width and length to enhance the signal flow or integrity.

The current carrying capacity of a PCB is determined by a specific standard known as IPC-2152. It shows the trace parameters, including the thickness and weight of the copper, and trace length and width. These parameters are interconnected, depending on a material’s thermal and electrical properties.

Role of the PCB Copper Thickness to Enhance the Current

Engineers use some calculations and equations during PCB design as discussed below. These calculations are 99% correct in many PCB designs, so let’s understand them.

1-Finding the Signal Power, P (W) and Voltage, or V (Volts)
You must know these quantities from PCB operation design.
2- Finding Trace Impedance, R (Ω).
You have to set it and you can manage it during the fabrication of the PCB.
3-Finding The Maximum Flow Of Current For The Trace I (A).
You can find the current by using the below equations.
I = V2/R or I = P/V or I = √ (P/R)

4- Finding an Increased Temperature T (°C).

You must know the increased temperatures, or you can evaluate it from the PCB operation design.

5- Finding the Cross-Sectional Area of the Trace A (Mils2).

It involves constants of curve fitting, such as k, b, and c that approximate the
IPC-2152 curve. This curve links the area to its current carrying ability.

K for internal layers= = 0.024, b = 0.44, c = 0.725
K for external layers== 0.048, b = 0.44, c = 0.725

A = (I/ (k ×Tb)) 1/c

6- Finding Trace Width or W, Mils

You should also set the trace width as required.

7- Finding PCB Copper Thickness? (Mils).

= A / w

You can use the PCB design software to set the thickness of copper, or you can use values of the copper weight, as most contract manufacturers use it. Such parameters are proportional to each other. Here is how to find the copper weight.

Copper weight (oz.) = (copper thickness (mils) / 1.37
According to the thumb rule, the weight of one square foot of copper is one ounce. If you follow the right equations, you can create a well-designed PC Board even for the first time.
What Is Heavy Copper And Why Do You Need It?
If the copper weight is over 4oz, you can consider it heavy because a standard weight or thickness ranges from 1 to 3oz. You can use heavy copper to have

  • More current carrying capacity
  • High capacity to bear thermal stresses and have good thermal management.
  • Better heat dissipation
  • Great mechanical strength to have large through-hole components and heavy connectors.
  • Power converters and planar transformers

Sometimes the PCB fabricators use 1 oz. copper for internal layers and 4 oz. for external layers of a multi-layer PCB. Certain issues can be controlled by using the same copper thickness in stack-ups of opposing layers, as it can eliminate the PCB bending due to heat generated during its function.

Like, if you have a PCB with 8 layers, you can group the opposing layers as 1 & 8, 2 & 7, 3 & 6, 4 & 5. That means layers 1 and 8 should have a similar thickness or weight, and the same goes for layers 2 and 7 and other groups.

What Is Copper Thickness And Weight In Printed Circuit Boards?

Copper is used in a PCB having a thickness of 1 oz., however, some engineers measure it in ounces. The thickness of copper determines the copper weight. Like, when the weight of copper covers one square foot of sheet, it makes copper thickness. Hence, 1 oz. of copper covering 1 square foot will result in 1.37 mils or 0.0348 mm foil thickness.
Why You Have To Consider the Copper Weight In PCB?

You can determine the current carrying ability of a PCB with the help of the thickness of its copper traces or copper layer. For PCBs with well-controlled impedance, the trace width helps determine the essential copper thickness. Besides, some other factors are also essential, such as a circuit board’s weight, compatibility of PCB components, and the type of connectors on a PCB.

Does Copper Weight Affect The Cost Of PCB Construction?

A printed circuit board with heavy copper involves expensive manufacturing, besides, it needs more time to make it. In other words, thicker copper is always more costly than standard copper. The manufacturing time of heavy copper is also high that also increases the total cost of PCB manufacturing.

What Is Etching In PCB?

In etching, you have to remove additional copper from traces and several other parts of the PCB, like pads and angular rings. Fabricators use an ammonia-based liquid to complete the process of etching.

How To Determine The Current Capacity Of A Printed Circuit Board?

The current carrying capacity of a PCB is determined by a specific standard known as IPC-2152. It shows the trace parameters, including the thickness and weight of the copper, and trace length and width. These parameters are interconnected, depending on a material’s thermal and electrical properties.

Final Thoughts

PCB involves different materials, including copper that have certain parameters, including thickness and weight. The copper thickness has a direct link to the current flow and the signal integrity, so its knowledge is essential for PCB designers, engineers, and fabricators. PCBs with heavy copper help create more reliable devices with increased current flow and better performance.

However, many smart devices have thin copper layers, depending on their requirements. You can develop a flawless circuit board by considering copper weight, thickness, as well as trace width and length, and several other features as described above. Besides, you must hire a good fabricator in this case.

Would like to know more about PCB Copper thickness and current or PC Board assembly? Email us at sales@pnconline.com

PCB Design Guidelines For Reduced Electromagnetic Interference

PCB Design Guidelines For Reduced Electromagnetic Interference

Printed circuits should be well designed and well-built to help devices work accurately. These circuits should have good materials to minimize certain issues, including the high EMI or electromagnetic interface. On the other hand, poor design can cause weak signals and high radiation, disabling the device. Here, we will discuss all essentials of EMI and how to reduce it.
Electromagnetic interference or EMI is defined as any disturbance that affects an electrical circuit due to either electromagnetic induction or electromagnetic radiation. The effects of EMI can range from a simple degradation of signal quality to complete equipment failure. In order to avoid these negative effects, it is important to design your Printed Circuit Board with EMI in mind.
Reduced electromagnetic interference (EMI) on your circuit board ensures that your electronic devices and products don’t interfere with nearby electronics and may even improve the overall performance of your products. We will share some key tips that you can follow to help reduce the EMI generated by your circuit boards and improve the performance of your final products.

PCB Design Guidelines For Reduced Electromagnetic Interference
PCB Design Guidelines For Reduced Electromagnetic Interference

Optimizing the EMI PCB Design

Electromagnetic interference has many reasons,and you have to reduce it through the filter.You can create the EMI filters using a single component or a network of many components having dedicated circuits to reduce different mode noises. Now, we will discuss the EMI filter design and its standard types.
After deciding on the basic EMI design, you will have to optimize it through a circuit board’s specifications. Like, if the purpose of the EMI filter design is to drive other PCBs, you must add more filter elements to have smoothing, isolation, and limits of electrical parameters. The limitof meeting the board’s needs depends on the PCB design capabilities and the available analysis methods.

How PCB EMI Happens

You will see electromagnetic frequencies everywhere all around you, such as appliances, or electronic products having current. EMI falls into different categories when it comes to PCB.

  • High-power devices cause EMI, like amplifiers, antennas, processors, FPGAs transmitters, etc.
  • Moreover, the change of components can also cause interference affecting g the device.
  • EMI often occurs along traces and at connector points. Unnecessary coupling occurs between the ground planes and signal paths because of lost capacitance.
  • EMI also happens due to external sources, like when the board is near a source that emits radiation. This external source can be a device, equipment, or some other circuit board.

It is very hard to eliminate all types of EMI sources, but following certaindesign rules can help in this case. You can minimize the disturbing noises through different techniques that we will describe in this article.
What Are EMI Design Guidelines?
Like every PCBoard, there are certain design parameters to follow while designing a suitable EMI filter design. You have to adopt a certain perspective in this case, as described below.
PCB Design Perspective 2-Dimensional
First of all, you have to make marks for component placementwhich you can do through a design software library, or you can upload a file taking it from other sources. It also involves spacing, routing of traces, and design clearances. But, you will have to consider a few things to do so, such as:

  1. Make sure that component libraries and pads are compatible.
  2. There should be a maximum distance between the adjacent elements, such as traces, pads, and annular rings, as it will reduce the EMI.
  3. Designers should consider the types ofsignals for component partitioning.
  4. Make sure that the trace size or width is according to the required current capacities.
  5. The impedance compatibility should be addressed in terms ofexcellent power transfer and differential routing.
  6. Make sure to provide thedepenalization according to the terms and conditions of the board clearance.
  7. Devices with high radiation should be shielded.
  8. Silkscreen should be used wisely to enhance PCB assembly through reference points and component polarities.

Various Techniques To Minimize EMI

Design should involve minimum EMI, and you can achieve it by adopting different techniques.

Reducing The EMI Through A Ground Plane

The first barrier against EMI is the ground plane, as PCB needs a floating surface to function effectively. Printed circuit boards have a ground plane to give a reference line of 0 volts and take it to the power supply terminal for a circuit’s return path.

The circuit board becomes an antenna when there is noise due to ripples. A circuit board’s copper foil or the ground planeoccupies the maximum cross-sectional area of the circuit board. So, you can reduce the EMI or electromagnetic interference by effectively using the ground plane.

Reducing EMI Through Trace Layout

The conductive paths on the circuit boards are known as traces. Flowing electrons occur in traces due to an active circuit and are a little away from developing a radiating antenna.There are certain guidelines to follow regarding trace layouts, such as:

  • There should not be bends with sharp angles. Instead,round right angles are suitable to reduce reflections that occur due to an increase in capacitance in the corner areas lying at 45 degrees.
  • High-speed traces should be away from the low-strength signals. You can take an example of a clock that has high-speed signals. Whereas analog and digital signals should also be separate from each other.
  • The return paths should not be long, instead, make them short.
  • The differential traces should be close enough to enhance coupling. This techniquebrings influenced noises into a less problematic mode.
  • There should be a wise usage of vias as they help you take benefit of a circuit board’s multiple layers while routing.Designers should know that thereflections happen due to a change in impedance.
  • Different traces should not have vias. However, in case you need so, then you can have an oval anti-pad which two vias share, reducing the parasitic capacitance.

SomeWays of Reducing EMI from Components

  • Try to choose low-power consumption components.
  • You can use USB circuits within an enclosure, like PCB guards or Faraday cages. They can also eliminate the EMI from the circuitboard’s surroundings.
  • Use heat dissipation methods to avoid the EMI. Proper heat sinks and vias help in this case.
  • All the above techniques and guidelines can help you reduce EMI. But, the design, function, and PCB performance goals determine the EMI reduction technique you should choose.

Some Other Ways

Place decoupling capacitors close to the power pins of your ICs. These provide more capacitance closer to the source, reducing both conducted and radiated EMI.
Make sure you are soldering all components with enough solder so that there is no exposed metal at any point on the circuit board.
If possible, position sensitive analog circuits such as amplifiers or comparators away from digital circuits such as processors or microcontrollers.
Shielding (copper foil) can be used in conjunction with shielding paint to improve RF performance further. Shielding paint is usually made of copper powder mixed into an acrylic binder. The copper reacts chemically with air, so shielding paint should not be used in damp environments where there may be high humidity or condensation levels. In most cases, paints will have a shelf life of up to five years if stored in a dry place without exposure to sunlight.

EMI Optimized Circuit Board through PSpice

There is a simulation tool known as PSpice which can help you to analyze the electrical parameters of a PCB design. However, it should be done before submitting your design for construction.
Ithelps evaluate heat dissipation and distribution methods, different simulations, anda circuit’s behavior in different conditions.
You can use the PSpice Advanced Analysis tool for this purpose. You can optimize a PCB for minimizing EMI by following the design guidelines and using advanced methods.


What is EMI in PCB?
Electromagnetic interference or EMI is defined as any disturbance that affects an electrical circuit due to either electromagnetic induction or electromagnetic radiation.
How To Reduce EMI?
You can reduce PCB EMI through traces, a ground plane, PSpice, and some other methods.
What Are the Reasons For EMI?
High-power devices cause EMI, like amplifiers, antennas, processors, FPGAs transmitters, etc. The change of components can also cause interference affecting the device.

Wrap Up

Electromagnetic interference (EMI) from power lines and high-voltage devices can damage circuitry, which can lead to failures in equipment and even safety issues. This article focuses on PCB design guidelines that will help you prevent EMI on your PCBs by making them less susceptible to outside interference, particularly during the power-up sequence.
By applying the guidelines described in this article, your designs will have lower susceptibility to radiated emissions, conducted emissions, and common-mode currents, making them less vulnerable to damage from outside sources of EMI.
Would like to know more about design guidelines for reduced EMI or printed circuit board assembly? Email us at sales@pnconline.com

Printed Circuit Board FR4 Material

Printed Circuit Board FR4 Material

FR4 is a blend of fiberglass and epoxy resin, and manufacturers also call it a composite material. It resists flame and is highly used for PCBs as a substrate or base layer. FR4 circuit boards are now used instead of G10 boards due to their properties.

FR is also a great electrical insulator because it is completely water-resistant which means it does not absorb a little drop of water. Such qualities mechanically make it very strong and it maintains its qualities in all kinds of weather, including humid, hot, and dry weather.

Properties of FR4

FR4 is an inflammable material, and it is UL94V-0 compliant which means it does not spread fire, instead, it stops fire the moment the material starts burning. It has bromine that resists fire and does not absorb water as described above.
Moreover,the glass transition temperature is very high ranging from 115 to 2000 degrees Celsius, depending on the type of the resin and manufacturing method.Mostly such PCBs FR4 lies between the two layers of copper laminates.

Types of FR4 Material

FR4 material has different types, such as:
Standard FR4: Its heat resistance goes up to 140-a50 degrees Celsius.
High CTI FR4: The index of this type of FR4 goes beyond 600V.
High TG FR4: It has a high-glass transition value, such as 180 degrees Celsius.
FR4 without copper: This type of FR4 is suitable for insulating plates, and it can support the circuit board.

How To Choose The FR4 Thickness

FR4 thickness should be decided carefully as it contributes a lot to the applications of different PCBs. You should consider the following things in this case:

  • Design and flexibility
  • FR4 thickness should be compatible with components
  • It should not take much space on a PCB
  • Focus on the type of desired connections

Advantages of FR4

FR4 is cheaper than other substrates of circuit boards which makes it a standard material to develop small circuit boards. But, it is not good for high-frequency circuits or where the parts are suitable for flexible circuit boards.
FR4 is often suitable for RF applications with a frequency from 1GHz to 10 GHz. However, electric products having an FR4 have some disadvantages due to certain limitations.
FR4 material is one of the most popular choices for printed circuit boards because it offers a high degree of strength and rigidity. This means that your PCBoard will be less likely to warp or bend over time, which can lead to reliability issues. As already mentioned, FR4 material has excellent thermal stability, meaning it can withstand high temperatures without breaking down. This makes it ideal for use in harsh environments or in applications where heat dissipation is a concern.
As FR4 material is one of the most affordable materials on the market, which makes it is a great option for businesses on a budget. In addition to being cost-effective, FR4 material is also easy to work with, which can save time and money during the manufacturing process. It can be machined in a variety of ways, including deep draw and laser cutting, so customers are not limited in their design options
FR4 material is a great choice for PCBs because it offers good electromagnetic shielding. This means that it can help protect your circuit from outside interference. Additionally, FR4 is flame retardant, which makes it a safer option for use in electronic devices. It’s also strong and durable, so you can trust that your PCB will last for years to come.
It’s important to note that there are many different grades of FR4 material with different properties, so make sure you know what you need before ordering.

Some things worth considering when choosing an FR4 grade include: whether the PCB needs to support weight, how sensitive the device will be to temperature changes, how strong it needs to be, and how much flexibility is required.

Understanding PCB and Its Materials

Printed circuit boards manufacturers involve many steps, including design and finishing, leading to a huge production. Printed Circuit Board designers and engineers should consider the material in terms of its properties and applications. They should have it in Gerber files before sending the PCB design for manufacturing. In other words, PCB material determines the end product. Various PCB materials include the FR4, Teflon, PTFE, etc.
PCB substrates are made of phenolic and proxies, whereas PTFE is more costly than all others. Different PCB materials are available in the market, and you should choose them according to your needs.

Types of PCB Materials

Mostly PCB has four layers which are made one by laminating through a heating process. Each layer hasa specific PCB function and needs a specific material. PCB designersshould have full knowledge of materials in terms of their properties which should be suitable for specific applications.The end product with PCB is a specific device that needs a specific material, so it is a crucial factor.
PCB is composed of different materials from the base to the top, including copper, substrate or base layer, copper, solder mask, and silkscreen.
The subsequent layer of PCB is copper which is placed and bonded over a base material with heat and adhesive. The thickness of the copper layer is used according to the PCB and its application. Like, you can make it in one or two layers, depending on your needs. Mostly, cheap devices or gadgets have PCBs with a single layer of copper.
Like FR4, copper used in the circuit boards has different types in terms of resin, such as PF resin, epoxy resin, and polyester resin.
On the other hand, the silkscreen layer helps make marks or letters for programmers to read on a printed circuit board. The layer below a silkscreen is a solder mask and don’t forget to read our special post on solder masks.You can choose PCB materials by yourself or through an expert.

What is the FR4 Trace?

FR4 thickness is often 1oz,2oz, or 3oz, and the copper layer can be populated according to the design. It is also tested against the UV rays before removing the chemical solution to have correct copper traces which connect different parts on the FR4 PCB.
FR4 PCB trace can have signal issuesdue to mismatcheddriver’s and receiver’s impedance. Such an incompatibility results in bumps on the layer that reflects signals at a receiver’s end, sending them back to the copper trace.
The signal reflection that occurs due to mismatched impedance can affect the signal integrity. So, as a thumb rule, you should be careful, especially if the edge rate is lower than 1/6 of the propagation gap or delay in the copper trace’s length.
In the case of copper trace, signals occur 1 inch in 6 ns. You must take care of measurements to manage the impedance, especially if the edge rate is 1ns, whereas the copper trace is larger than one inch.

Printed Circuit Board FR4 Material
Printed Circuit Board FR4 Material

How To Manage The FR4 Trace Impedance

  • You can use resistive matching to make the driver and receiver’s impedance compatible. Such a technique involves a resistor having a value according to the source impedance. The resistive is set parallel with the receiver or in a series, depending on the requirements.
  • Some other techniques also help in this case, minimizing the signal reflection. A long PCB trace causes high-signal reflection. So, you can also reduce the trace length in a circuit board to overcome the signal reflection.
  • A signal’s return path is also important in this case because impedance can happen anywhere, including the signal trace or returning path.
  • If PCB has high-frequency signals, you should route the traces on the plane of a returning path. But, don’t route signals on a split plane because it would result in a discontinued impedance.
  • You must use advanced PCB design or analysis techniques to get precise results. The tools should possess advanced simulation.

Wrap Up

FR4 material is the standard fiberglass laminate that you’ll find in all PCBs (printed circuit boards). It has many uses, and each one will likely have its own set of requirements for using FR4 material. You’ll need to keep your specifications in mind when looking at FR4-based materials, but this will give you a good idea of what kind of FR4 laminates are available on the market today.
The FR4 board can be easily cut with a knife or saw and drilled through using a drill press or electric drill. You can even shape it using files or sandpaper if you need to, which makes it versatile as well as economical. So if you’re looking for high-quality circuitry in your next project, take a good look at what this particular type of PCB has to offer before making any decisions.
Would like to know more about the FR4 material or PC Board assembly? Email us at sales@pnconline.com

PC Board Color- Choosing Your Desired Color

PC Board Color- Choosing Your Desired Color

PC Board come up in different colors of which a green solder mask is the most common one. You will see most circuit boards with green solder masks. But, the industry is getting innovative due to changing technologies, so designers try new colors to make printed circuit boards.

PCB Solder Mask

Before getting into PCB colors, you should know what the solder mask is? The printed circuit board has different layers, and the top layer is the solder mask, whereas the bottom layer is the copper foil. The purpose of the solder mask is to cover the bottom layer from getting polluted or oxidized. The main material of solder masks is often the insulating resin which is printed on the circuit board’s unsoldered areas. The resin protects the board from heat, moisture, and any kind of damage.

Printed Circuit board Fabrication

You can customize a circuit board in terms of solder masks and other elements. According to research, 99% of solder masks are green. However, other colors are also emerging, such as red, black, white, yellow, blue, and purple. These colors are used for different applications. Such as RDs at the NPI stage are often made red. Whereas white is used for LED light circuit boards.
Each PCB color has some good and bad aspects that we will discuss here.We will also help you choose the right PCB color according to your application. Let’s start with the colorgreen.

Green Solder Mask In PCB

Though many colors are there, the green solder mask is still at the top as it helps to visually inspect the PCB to find any defects. Moreover, green makes a good contrast with the white silkscreen, helping you to remove the flux residue. If you don’t know how to select a color for the solder mask, go for green right away.

PC Board Color- Choosing Your Desired Color
PC Board Color

Red Solder Mask In PCB

Red is another color for PCB solder masks,and it adds brightness to the PCB. Red has a nice contrast with planes, areas without copper, and traces. However, the contrast is less than a green circuit board.
You may need a magnifier to find any defects in the traces. However, the red solder mask is compatible with screen printing and also helps remove residual flex like a green solder mask.Red also enhances a device if the circuit board is visible.

Blue Solder Mask In PCB

PCB with a dark blue solder mask is also popular. It hasless contrast with the planes, traces, and no-copper surfaces.Hence,you have to use a magnifying glass to inspect the construction defects. But, it has a high contrast with screen printing that makes blue suitable for a PCB with several components.
But, blue is less clear than green and red, and it highlights the dirt that makes it hard to remove the flux residue. A bluesolder mask is ideal for boards with hidden routes. It is also compatible with Arduino open-source tasks or products.

Black Solder Mask In PCB

A black solder mask is not so ideal in terms of inspection, as planes, traces, and no-copper surfaces have less contrast. Other than a strong magnifier, you also have to rotate the light to create a shadow to highlight the trace.
However, there is a good contrast of screen printing, and it’s visible on the board without any lights and so are the pads.But,the black solder mask has a high heat absorption during reflow. You have to place a temperature checker near the board while manufacturing. Moreover, the screen printing gets light brown during reflow due to the board’s high heat absorption.
The dirt also gets more prominent on the black surface, making it hard to clean. That’s why the manufacturing of a black PCB board involves more cost than other colors. On the other hand, black is ideal for LCD panels.
The black solder mask has two types, including matte and gloss of which matte black contrast is better than the glassy black.However, a black solder mask gets soiled and it becomes hard to repair it.

White Solder Mask in PCB

White solder masks have the lowest contrast than other colors, and placement of the marks becomeshard evenif they are under lighting. Whereas the cleaning of a white Printed Circuit Board is so difficult that you can’t imagine. You have to do so much effort to remove the stains from a white PCB.
However, it has some benefits as black printing on a white PCB creates a good contrast. You can use a white solder mask in LED applications where the front panel has to be white to increase the brightness.

Yellow Solder Mask in PCB

Yellow PCB is as good as green because there is a high contrast between theplanes, traces, and no-copper surfaces. You can use the dark yellow mask to enhance the routes, making them prominent.
There is one disadvantage of using a yellow solder maskand that is it’s less contrast with the white silkscreen. Many manufacturers prefer a black silkscreen with a yellow solder mask, even though it is less satisfactory.
It is easy to clean the residue from a yellow solder mask.So, yellow can be a great choice even though some people don’t like a lively color like this.

Purple Solder Mask in PCB

Purple PCBs are rare, however, advanced devices can have such boards. Purple has good contrast with the traces and planes. However, it does not go well with white silk printing. But, a purple solder mask would look great with an immersion gold surface, creating a good match.
So, you can choose any of the above colors to customize your PCB, depending on your requirements.
Why Should You Use Different PCB Colors?
It is not enough to know that PCB has different colors, because one should also know its reason. There are a few reasons behind using different PCB colors instead of just green, such as:

  • Different PCB colors help engineers indicate the revisions and changes to help users recognize them.
  • The application of other colors in PCBs can create better contrast. You have to understand the importance of the assembly tools in terms of transmission light, reflectance, and absorption.
  • Different PCB colors can reduce the errors caused by a mixed assembly. Moreover, the contrasting colors help decrease lead-free meetings.
  • The colors of the printed circuit boards are known as PCB codes. You would see modern PCBs in different colors compared to traditional boards. Even today, the PCmotherboard’s color is green epoxy because of its qualities
  • Though the colors of the PCB solder mask don’t influence a board’s performance, they can enhance its resolution. However, solder masks with clear transparency have a high resolution. The yellow and black PCB resolution is less than other colors like green, red, and purple.

Hope the above discussion helped you understand different PCB colors along with their advantages and disadvantages.


What Is PCB Solder Mask?
The printed circuit board has different layers, and the top layer is the solder mask, whereas the bottom layer is the copper foil.
How Many PCB Colors Are There?
PCB comes up in several colors, such as green, red, black, white, yellow, blue, and purple.
What Is the Green Solder Mask?
The green solder mask makes a good contrast with the white silkscreen, helping you to remove the flux residue.
Is Red Solder Mask In PCB Effective?
Yes,the red solder mask has a nice contrast with planes, areas without copper, and traces.
What Is The Reason Behind Different PCB Colors?
Different PCB colors help engineers indicate the revisions and changes to help users recognize them. They reduce the errors caused by a mixed assembly. Moreover, the contrasting colors help decrease lead-free meetings.
Why Engineers Don’t Prefer Black Solder Mask?
A black solder mask is not so ideal in terms of inspection, as planes, traces, and no-copper surfaces have less contrast. Moreover, it gets dirty and is hard to clean.
Where Can I Use A Purple PCB?
The purple solder mask is compatible with an immersion gold surface, as both match very well.

Wrap Up

The green solder mask is the most common in circuit boards due to its high contrasting ability. The purpose of the solder mask is to cover the bottom layer from getting polluted or oxidized. The main material of solder masks is often the insulating resin which protects the board from heat, moisture, and any kind of damage.
Many users customize a circuit board in terms of solder masks and other elements. You will see various PCB colors in different applications, such as RDs, LEDs, PCs, etc.
Would like to know more about PCB Colors or smt assembly? Email us at sales@pnconline.com