What is a PCB? Printed Circuit Board Guide

What is a PCB?

Printed Circuit Boards (PCBs) are the foundation of nearly all modern electronics. Manufactured from thin, insulating panels, PCBs contain metal coatings with etched electrical pathways that allow current to flow across various components. PCB manufacturing begins with a bare board, which undergoes precise layering, drilling, and etching processes to create a fully functional circuit board. This article details the PCB manufacturing process, from creating bare PCBs to assembling complete, operational boards.

(A fully functional PCB circuit board)

1. PCB Circuit Board Blank-Ultimate Free Advice and Guidance

1. What Is A Blank PCB circuit board?

A blank printed circuit board is an empty or unused board free from any physical contacts and devoid of pieces installed and used during the creation of an actual circuit board or a printed circuit board.

(A typical blank green PCB board)

2. Blank PCB Circuit Board Supplier

There are hundreds of blank PCB board suppliers in business ready to provide you with bare PCBs. However, to ensure that you get your PCBs on time, you may want to partner with an experienced supplier. Choose reputable suppliers with decades of experience.

3. Blank PCB Circuit Board: 5 Questions You Care About

3.1 How Thick Is The Copper On The Blank PCB Board?

The thickness of the copper on a blank PCB board will influence the board's functionality and performance. But the width of the copper depends on the requirements of your bare PCB. That’s what will determine the level of depth that suits you.

3.1.1 Uses of Thick Copper on Blank PCB Board

Thick copper on blank PCBs is commonly characterized by structures that contain copper thicknesses ranging from 105 to 400 µm. Thick copper PCBs find a lot of use in high current outputs and the optimization of thermal management.

3.1.2 Benefits of Using Thick (Heavy) Copper Circuit in a Blank PCB Board

There are plenty of benefits associated with using a dense copper circuit in a blank PCB. For instance, it brings about increased carrying capacity for the current, increased endurance in terms of thermal strain, and increased mechanical strength, especially at connector sites. Additionally, it leads to efficient heat transfer through the board.

3.2 How to Create a Blank PCB Board in Eagle

Creating a blank PCB board in Eagle can be a tedious task. But when done in the right way, then it’s quite simple.

3.2.1 Getting Started

First, you’ll have to download the Eagle software on your computer and install it. After installation, you’ll have access to the control panel of Eagle. Just click on the ‘control panel’ then select New Project. Choose a name for your project and then right-click on it. Select New Schematic.

3.2.2 Designing Your Blank PCB Board Schematic

After opening a New Schematic, it will open some Blank workspace from where you’ll draw your board’s schematics. Ensure that the grid size is 1 mm before adding anything to the PCB schematics. Select Add Option if you want to add components to the schema.

Now, connect all the components in the schematic editor by clicking on the Net option. Don’t forget to save the schematic file. Choose the parts that like and click OK. You can now go ahead and add every element needed to complete the circuit. Rename the file to a name that’s easy to understand.

3.2.3 Blank PCB Board Layout Design

Now proceed to design the PCB layout by clicking on the Switch to Board icon. You will see a new window consisting of a black space that dominates a significant part of the screen. You’ll also see a grey area on the left. The black room is your Board Area, while the screen is the printed circuit board Layout Editor. Move all the components from the grey part to the Blackboard and position them as desired.

By using the Route tool, make connections from one pin to the next. After you complete making the connections, check for errors. The board file will save as a .brd extension, and now, the computer-generated PCB board is ready for manufacturing.

3.3 How to Use Blank PCB Board

A blank PCB board serves as the foundation for the fundamental components that will make the actual functional PCB. It’s a blank slate used to place essential elements. A blank one is useless if it lacks all the components required. There are two main ways of doing this; Surface Mount Technology (SMT) and Through-Hole Technology.

3.3.1 Advantages

Some advantages of SMT include:

• Gives room for higher component density, meaning that many components can fit in a small area.
• It’s easy to place components on both sides of the board.
• Low production costs.
• Vibrations and shaking don’t hinder performance.
• Fast and consistent circuit production.

3.3.2 Disadvantages

• Unsuitable for high-voltage, high-power, and huge components.
• It’s prone to damage under harsh thermal conditions.
• It’s tasking to repair due to small-sized components.
• Unsuitable for components that require constant disconnecting and connecting.

3.3.3 Through-Hole Technology

The through-hole technology is another mounting technology involving the drilling of holes in the blank PCB. It includes inserting leads on the board and soldering the tips to the pads on the other side of the PCB.

3.3.4 Advantages

• It’s an ideal choice for large circuits where higher power and mechanical stress are typical.
• Reliable compared to SMT as components tend to bond on the board strongly.
• Perfect for systems that need high heat tolerance.
• Suitable for aerospace and military applications.

3.3.5 Disadvantages

• High production costs.
• The assembly process is somewhat complicated.
• Slow speeds of production.

3.4 How to Connect Components to a Blank PCB Board

A lot of people know that the process of connecting components to a PCB goes by the name mounting. However, the method in itself is known as soldering.

3.3.4 Soldering

Soldering is the process of joining two or more items to one another by melting solder or a filler material between them. Soldering is a perfect solution for joining electrical parts as they won’t be damaged. Regular soldering irons are ideal for easy projects. However, industrial production requires complex machines that produce high-quality connections.

3.4.2 Desoldering

Desoldering involves the detachment of components/parts from a PCB. Desoldering is all about getting rid of the solder material, solder connections, and other elements from a PCB. All this is done either for repair, salvage, or replacement.

3.5 Where to Buy a Blank PCB Board

To be honest, the process of designing a blank PCB is a tedious task better left to experts in the field. Our advice is that if you can’t make one on your own, then there’s no harm in purchasing one from experienced manufacturers.

3.5.1 How to Find a Reliable Supplier

Looking around today, you’ll notice that there are hundreds of blank PCB suppliers in the market. Unfortunately, not all of them are who they say they are. Some of them deliver poor-quality bare PCBs that don’t meet the required specifications. To be on the safe side, you need to keep the following at the back of your mind:

3.5.2 Company Brand and Experience

Company brand and experience matters when it comes to selecting a blank PCB supplier. What are other people saying about the supplier of your choice? How long have they been supplying bare PCBs? Are their reviews positive? Ensure that you deal with reputable brands with decades of experience.

3.5.3 Manufacturing capacity

It would be highly disadvantageous on your end if you work with a supplier who can’t meet your specific needs. You need to ensure if your supplier is outsourcing part of the manufacturing processes. In case there’s some outsourcing, then scrutinize the firm to ensure that they can meet your needs.

3.5.4 Cost and Quote Reference

Manufacturing costs are crucial when looking for a blank PCB supplier matters a lot. Low-quotes are signs of low-quality standards of production. But again, huge quotes would be disastrous if the boards fail to correspond with customers’ design specifications.

3.5.5 Excellent after-sales services

The actual quality of a stellar PCB supplier is in their after-sales services. A reputable supplier is one with procedures aimed at assisting customers once they’ve purchased a product. Go for suppliers with informed and polite customer care attendants ready to help you in case you run into some problems.

3.5.6 Expert Tips to Consider When Buying

When purchasing blank PCBs, ensure that you only purchase from reputable suppliers known for high-quality deliveries. Also, ensure that your supplier complies with iso9001, UI, and RoHS standards. Don’t forget to check whether your supplier has a healthy working relationship with component distributors too. Lastly, don’t always go to a one-size-fits-all supplier. Shop around to find the best in the market.

3.5.7 Where to Get Quality Blank PCB Board

You may find several companies supplying blank PCB boards if you want to get high-quality bare PCB. In that case, you can choose PCB companies with more than ten years of production experience and believe that they can deliver high-quality PCB boards that meet industry standards.

(close up image of a bare PCB)

2. Standard PCB Panel Size-What You Need To Know

Are you new to the PCB world? If so, then there are a few things that you need to know. In this section, you’ll learn essential elements such as the PCB's panel size, the standard size of the board, and fabrication panel size, among others. Here are a few things to note:

1. PCB Panel Size

Every PCB has got a reason for their making. Because of this, you’ll find that there will be different sizes and kinds of printed circuit boards in the market. Various methods of penalization exist. To come up with the desired function and size, manufacturers use other methods. Also, the size of the panel matters as boards with large panels may cost more to manufacture.

2. Standard PCB Panel Size

When talking about the stand PCB panel size, discussions about the circuit board's thickness often come up. If the width isn’t measured correctly, then the PCB won’t function as intended. When talking about the standard PCB panel size, then the average circuit board's thickness has to be 0.063 inches.

3. PCB Panel Standard Size

PCB panel standard size is also something that you need to know when it comes to blank PCBs. To a typical PCB maker, the panel standard length of the PCB should be 18 x 24 inches. PCB panel standard size may affect the efficiency and functionality of your board. A majority of manufacturers choose to use the standard size, mainly to minimize manufacturing costs. Additionally, the standard length is easy to configure, meaning less work for manufacturers.

4. PCB Fabrication Panel Size

The construction of a PCB using the standard PCB panel size is beneficial to manufacturers as it makes everything faster and lighter for them. Blank PCBs have different panel sizes. Therefore, it’s essential to know how to decide the type of fabrication panel size ideal for your circuit boards. If you get PCBs containing dimensions out of the standard PCB panel size, you need to be keen when selecting your PCB's panel size.

(engineer measuring multimeter panel board)

3. Standard PCB Thickness – Determine the Right Standards

1. Standard PCB Thickness

As noted earlier in the text, the standard thickness of a PCB is 0.063 inches or 1.57mm. The reason as to why the standard width is 0.063 inches is simple to understand. During the plywood industry, the width of the plywood sheets stood at 0.063 inches.

1.1 PCB board thickness

Several decades back, both the top and bottom layers of a PCB contained Bakelite as a manufacturing material. With such, the thickness was 0.0065 inches. But over time, the use and substrates and other materials saw PCB thickness reducing below 0.0065 inches.

1.2 PCB copper thickness

Copper is an essential material that dictates the functionality and application area of a PCB. Mostly, the 1 oz of copper goes into the manufacture of PCBs. Also, this is presumed thickness by PCB manufacturers. But suppose current has to pass through the board, then you’ll need more than 1 oz of copper.

1.3 PCB trace thickness

Trace thickness is the thickness that the designer gets to determine. Upon current increase, the copper traces will begin heating, and the temperature of the PCB rising. When the PCB can’t handle high temperatures, it starts getting damaged. But to avoid such cases, the trace has to be thick enough to give room for increased current flow.

2. Standard PCB Fr-4 Thickness

Fr-4 stands for flame retardant, while the four stands for the class of the accompanying materials employed. Fr-4 thickness is typically measured either in inches or millimeters. Usually, the standard PCB Fr-4 depth is from 3 inches to 10 inches.

3. Standard PCB Core Thickness

When manufacturing a standard PCB core, some things to consider, such as the copper foils used in the formation of Fr-4 materials. They have to be smooth and exact in thickness. However, the typical PCB core thickness should stand at 0.063 inches or 1.57mm. It is the standardized level defined for long.

3.1 PCB core thickness range

The weight of a PCB core thickness does range from half an ounce to three ounces. You need to remember that the value includes the copper material. But if a manufacturer makes a PCB with different copper weights, it may amount to increased charges and low functioning PCB. To achieve the right PCB core thickness, you may consider using pre-preg sheets to make the desired thickness.

4. Standard two-layer PCB Thickness

Over time, we have witnessed the development of multiple-layered boards. With technology continuing to advance, multiple layers give room for additional loads while still maintaining a thickness of 63mm. Now, we have PCBs with several layers, as discussed below:

4.1 Standard two-layer PCB thickness

Also known as a double-sided PCB, this is a PCB that contains two copper layers with some substrate layer between them.

4.2 Four-layer PCB thickness standard

These consist of four layers aimed at routing electrical signals. The thickness standard of a four-layer PCB is 0.125 inches.

5. PCB Thickness Tolerance

Thickness tolerance is the allowance of the substrate employed in the manufacturing process of a PCB. Of importance to note is that this may either be little or more of the material's actual amount.

(a close image of a thick PCB)

4. Multilayer Pool – What You Need To Know About Multilayer PCB

Suppose you happen to be new to the world of PCBs. You may be surprised to find out that there are PCBs with more than a single layer. In the section, we’re going to look at different layers of PCBs.

1. What are potent PCB Layers?

All electronic devices that we use today contain PCBs in them. Some have PCBs with a single layer while others with many layers. PCB layers refer to the number of layers that you’ll find on a given PCB.

2. Layer Stack-up

Layer stack-up is the arrangement of copper layers and insulating layers to develop a PCB before layout design. Stack-up allows engineers to reduce external noise, cross-talk, and radiation. With proper PCB stack-up, engineers achieve high signal integrity.

3. PCB Layers Type

The purpose and application of a PCB will determine the number of layers that it needs to have. Below are some of the PCB layers types:

3.1 One Layer PCB

As the name suggests, these are PCBs containing only one layer of soldered and laminated layer of dielectric and conductive material. It’s simple to design, meaning that their production is achievable in bulk. You can find them in primary office and home appliances such as alarm clocks and calculators.

3.2 Two Layers PCB

Also, going by the name double-layer PCBs, these contain two layers of the substrate material. They are common almost everywhere, based on their higher capacity and flexibility. Also, they are less complicated to produce.

3.3 Four Layers PCB

Again, as the name suggests, a four-layer PCB contains four separate copper layers using in routing and power. They have an elaborate and stable design compared to single and double-layered PCBs. They are also very durable and ideal for both sophisticated and simple devices.

3.4 Six Layers PCB

These fall into the category of the most advanced multilayer PCBs: the power full industrial applications, electronic devices, and technology devices. Consisting of 6 layers, they are even more durable than four-layer PCBs. You can find them in laptops, computers, and data storage devices such as hard disks.

3.5 Eight Layers PCB

These are just like six-layer PCBs. However, they come with four plane layers and four copper signals. A majority of high technology devices and computer systems rely on eight-layers PCBs. You can also find them in industries such as governmental systems, aerospace, healthcare, and several other commercial applications.

3.6 Multilayer PCB

These consist of layers that can go up to 12 or even above. For example, ten layer PCBs have a total of six signal layers and four copper plane layers. Twelve layer PCBs are a bit more potent than ten layer PCBs. Multilayer PCBs find a lot of use in medical equipment, advanced computing, and high-tech applications.

3.7 32 Layers PCB

These are the most advanced multilevel boards out there. Their production requires a lot of precision and advanced manufacturing. They find heavy use in military and medical applications, and They offer high speed, high capacity, and high functionality.

4. Multilayer Pool

To design a PCB, you’ll first need software. For an error-free task, you may consider using Eagle software. Briefly, here are the stages:

4.1 Create a Schematic

A schematic is a foundation or a roadmap of designing your PCB. Make a drawing of where every component will fit. Using the Eagle software, you can use the tools available to replicate the handmade schematic you made before.

4.2 PCB Layout

After the schematic, now create your layout. You can either begin by drawing all the specifications on a board or selecting the appropriate grids to design your plan. You may also have to use the design rule check function, and it will help you achieve the final layout of your PCB.

5. Multilayer PCB

By now, you must be well aware of what multilayer PCBs constitute. These are PCBs with more than a single layer. Unlike single-layer PCBs, multilayer PCBs consist of high precision materials, meaning that their production costs are high. Now, let’s focus on the steps of coming up with a multilayer PCB.

6. DIY Multilayer PCB

The following are DIY multilayer PCB:

6.1 Adjust Library for Multi-Layer PCB Designs

(a multilayer PCB)

First, configure your CAD library to enable you to make multilayer designs. Here we can use these kinds of software. You can use software such as FreePCB, KICAD, or Design Spark to draw, design, and develop a PCB concept. An apt example of this was the initial release of A64-OLinuXino boards using Eagle software.

6.2 Negative plane layers

(hostile planes of a PCB)

You may have to use negative image plane layers to develop ground planes and power on your board layout. However, you need to ensure that the negative plane layers have proper clearances for using pad shapes and footprint.

6.3 Inner signal layer pad shapes

(an image of a cylindrical pad layer)

Pads on the inner and outer layers could differ. Some come in square shapes while others come in circular shapes. If possible, set up your library to achieve different pad shapes. An apt example of this is by looking at LEDs. A majority of them rely on cylindrical pad shaped PCBs.

6.4 Drawing pieces

(a schematic diagram of a PCB)

Draw the parts, but if you find this process difficult, you should seek help from a fabrication shop. There’s no harm in trying the services of an expert if you cannot draw the pieces yourself. An excellent example of this is looking at the services that we at OurPCB offer to clients in need of schematics assistance.

6.5 Design Tips

(ground planes of a PCB)

For greater signal integrity, use power and ground plane layers. You can also minimize pad sizes if the fabrication shop allows it. If using adjacent signal layers, route one signal layer horizontally and vertically on the second and third layers.

5. 10 Things You Should Know About Advanced Circuits PCB

1. Industries Covered by Advanced Circuits

As noted earlier, PCBs find their use almost everywhere. You’ll find them in phones, watches, cameras, laptops, and scanning machines. Industries covered by advanced circuits include the military, medical, automotive electronics, industrial equipment, and telecommunication equipment.

2. Selection of Advanced Circuits Materials

Unlike conventional PCBs, Advanced circuits find substantial use in equipment with high vibrations. They, therefore, require materials with the ability to handle heat and power effectively. For this reason, careful selection of their content is paramount.

3. Advanced Circuits Special Size

Size is essential when it comes to advanced circuits. Since they have to power high-energy equipment, then they have to be significant in format. Small-sized PCBs may not achieve the intended functions.

4. Type of Advanced PCB

Generally speaking, advanced PCBs range from double-layer PCBs to 32-layer PCBs. You need to choose one depending on the industry that you serve.

5. Demanding Operation Steps of Advanced PCB

Advanced PCBs find their applicability in high-precision electronic equipment that we usually use daily. Advanced circuit board fabrication is one of those tasking exercises that PCB designers have to undergo. It’s not an easy process to transform a PCB design from its layout to a physical structure.

When it comes to high-precision PCBs, there are several demanding steps that you need to pay attention to. Some of these challenging operation steps include heavy copper, attempting to reduce space covered by the motherboard, and drilling holes using a laser. These are some of those significant demanding operation steps associated with advanced PCBs.

6. Advanced PCB Production Equipment

It is simple to understand; you’ll require state-of-the-art equipment to manufacture advanced PCBs. To get the best quality, you must have detailed equipment;

7. AOI Tester

AOI Tester is a ubiquitous testing instrument; almost every PCB manufacturing factory has it.

(An engineer working on an AOI tester)

1. Flying Probe Electricity tester

The flying probe tester is an automatic test equipment that has been in use. Compared with other forms of automated test equipment, flying probe testers have many advantages in specific applications.

(Flying Probe Electricity tester)

2. Copper Thickness Tester

Copper thickness tester can instantly and accurately measure the thickness of copper foil.

(A copper thickness tester)

3. Metallographic analyzer

By a variety of grinding, polishing, and etching method of treating a metal surface. After preparation, analyze by optical or electron microscope. Using only metallographic techniques, skilled technicians can identify alloys and predict material properties.

(A metallographic analyzer)

4. Impedance tester

An impedance tester is an electronic device that a qualified technician can use to measure the ground loop's resistance level. Then, make sure it is low enough to allow enough current to flow through the circuit and operate the protection device when a fault is detected.

(An Impedance tester)

5. Metal thickness spectrometer

A metal thickness spectrometer can accurately measure the thickness of metal in a few seconds, which is essential in the PCB manufacturing process.

( An Impedance tester)

6. 2D Measuring Projector

It can quickly and accurately measure points, lines, circles, arcs, rectangles, and circles.

(A 2D Measuring Projector )

7. Complete Advanced Circuits Test Standards

Advanced PCBs require some of the best test strategies. For instance, you may consider using IPC test standards known to be the best in the field.

8. Life of Advanced PCB Circuit Board

The excellent shelf-life of an advanced PCB circuit board is around ten years, after which it may require some replacement. But there are several things that you can do to increase the life of advanced circuit boards. For instance, you need to pay attention to soldering.

Depending on the solder you use and the soldering method, you can increase your PCBs' shelf life beyond ten years. Additionally, you may have to ensure that you use industry-standard conformal coating applied by your manufacturer. Also, ensure that the storage environment is free from moisture and provide proper handling of your boards.

9. Future Development Trends of Advanced PCB Circuits

Based on forecasts, the advanced PCB circuit board will continue to grow. They’ll be a production of faster and efficient PCBs.

10. The Choice of Advanced PCB Manufacturing Firm

When looking for an advanced PCB manufacturing firm, ensure that you work with those who’ve been in the field for decades. Go for those with a good reputation and show value to their customers.

(A close pic of an advanced PCB)

Conclusion:

To sum it all up, without PCBs, electronic devices that we use daily won’t function as desired. The manufacture of PCBs begins from having in place a blank PCB with nothing on it. The placement of components takes place, provided the schematic and the layout is complete.

Depending on the function, you can choose the number of layers that you want. Are you in the market for some of the best PCBs that will work in your device without failure? You can contact us by email, and we can discuss more questions about the PCB circuit board.