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Getting to Understand about 3mm PCB

Are you interested in fr4 3mm PCB but do not know much about it? A 3mm PCB has the same size as a credit card and can fit in your wallet. This makes it such an attractive option for projects that need to be portable and need to be taken on the go. Many people also suggest that this size is perfect for international travel, so you can pack your project away in your backpack or purse and take it with you.

A green PCB material has low conductivity.

A wood-based PCB material has high conductivity.

This article will go over some of the key features of a 3mm PCB and its drawbacks. Also, we’ll go over some popular applications of this size of PCB.

What is 3mm PCB?

The PCB is the printed circuit board, a printed circuit layer assembled with electronics and components in an integrated manner on a flat surface. The simplest way to describe it would be as a printed circuit board with a thickness of only three millimeters. The thickness of a PCB board depends on the type of circuit material used. It can be 1 oz copper or 1-2 oz copper with another metal such as gold for better conductivity along traces on the board’s surface. For special types of circuits such as RF devices and high power battery circuits, other types of substrates may be required, and there are different names for these depending on their construction. The comparison of the surface area to the height makes this type of PCB perfect for smaller items. These boards are mostly used for portable accessories like cell phones, cameras, MP3 players, etc. Despite their relatively small size, they can still accommodate a large amount of circuitry within them.

Types of PCB Board

A well-known type of PCB is FR-4, which stands for flame retardant 4. It is FR-4 that is used for servicing the majority of electronic devices and circuits in the world today. This material is made up of a high-frequency glass fabric that has been impregnated with a thermosetting resin made from epoxy resin. The epoxy resin provides the necessary strength and rigidity for the board and its ability to withstand high temperatures during soldering.

Other types of PCB material include:

FR-1 is a flame retardant laminate with epoxy resin, but it will melt at low temperatures and is not recommended for PCB construction.

3mm thick FR-2 is comprised of an epoxy resin and a fiberglass fabric. This board has high rigidity, but it is not flame retardant and can burn easily with a hot iron.

FR-6 also contains glass fibers, but the resin used on this board is a vinyl ester. It is the same as FR-2 above, but it has a higher melting point. It can be used for very thin boards or double-sided boards.

Various conductive and insulating PCB materials are available: gold, silver, tin, tungsten, iron, copper, gold wire. These can be used for flexibility or high resistance circuits.

What are the advantages of 3mm PCB?

fr4 3mm PCB

3mm PCB is a small size circuit board; its size is smaller than a card. Especially fr4 3mm size is suitable for designing the smart-card application of small electronic components COSPLAY, which can be used in banking and payment cards, such as security devices. The weight of a green sheet is very light; it is easy to carry and use in mobile devices. What’s more, it has no space limitations with large quantities on export.

3mm PCB can be used for more than mobile phones, such as portable games, smartwatches, smart home appliances, and 3C electronic products.

This kind of circuit board is suitable for making small circuit board sizes to save material and reduce the weight and size of the electronic components. The miniaturization effect can bring the component size down by over 90% (compared with a general size of 15 x 15mm).

The circuit board is easy to carry;

There is no limitation for the export of large quantities;

The circuit board can be made into small sizes;

It has a good heat dissipation effect;

It can replace the general size of the electronic components by over 90%;

It is not easy to produce the radiation of electromagnetic interference.

Standardization and Form Factor

A 3mm design is only standardized when the oldest version is created. Since 3mm PCBs are so new, the design standards will change as time goes on and new versions are created. For example, a 3mm board designed for the newest version 1.4 will not fit on a 1.0 board because of the change in size from 1 to 2 inches.

Since there is no general standard for this size, you will need to find a manufacturer who makes 3mm PCBs that conform to your chosen design standards.

Solution-Oriented Integration

The 3mm design is the most open design format for boards. This means that it allows wireless connectivity and many other features that may be desirable in the end. Many people like this feature because it lets them customize their boards to their needs. For example, you might want a board that has Bluetooth connectivity. If you were using a 1.0 design, you would have had to buy a compatible module or use a costly adapter. However, with the 3mm design, you could easily integrate the Bluetooth module into your project and avoid paying for adapters or extra modules.

Low-Profile Design

With the 1inch PCB, there is no way to fit wireless components inside the board itself. This means that you should make your project as small as possible and try to place all of the components inside the PCB. However, with the 3mm design, there is a way to cut down on the size of your project. For example, you could place relays inside your board and eliminate the need for an external relay box.


Because the 3mm design is not as standardized as the 1inch design, parts can be more difficult to find or expensive if available. For example, you might need a Bluetooth module for your project. However, if you are using a 3mm design, you won’t buy this module because it won’t fit on the board.

Although these disadvantages exist, they can be managed or overcome with the right design and planning. Some of these problems will diminish with time as more and more people begin making projects with this size of PCB.

How to obtain 3mm PCB?

3mm PCB supplier, we can provide green and wood-based products through various processing methods. It has been widely used in aerospace, automobiles, communication, computers, and other industries.

The 3mm circuit board is becoming more and more popular for electronic products. The thickness of the board is very thin (about 2 mm). It is very difficult to produce the radiation of electromagnetic interference and has a good heat dissipation effect. Especially, it has no space limitations in large quantities on export. The 3mm circuit board can be made small, suitable for home appliances, such as smartwatches and other wearable electronics.

Selection of Components for PCB:


1. High-temperature resistance: The PCB contains thermal conductive material such as copper and silver. Electronic components are also made of metal materials, which can easily be oxidized if they are in contact with oxygen. The oxidation reaction generates heat. If the board is too thin or there is not enough thermal conductivity, it will melt or burn.

2. High mechanical strength: When the PCB is connected to the housing, it must withstand a certain pressure on both sides and maintain the design structure.

3. Compatibility: The board should be compatible with the electronic components, especially the connectors used. If it is not compatible before the assembly, it will cause short-circuiting or other troubles.

4. Low water absorption: This product should not absorb water or dissolve in water after manufacturing and installation. Otherwise, it will affect the circuit performance and promote corrosion due to moisture in the circuit board. It is easy to produce high conductivity (Can be used for telecom …)

5. Low cost: The cost is lower than other materials. This is an advantage for consumers as well as the manufacturer.

6. Strong, durable, and non-corrosive: The PCB can withstand high and low temperatures, does not react with water, and will not rust. The components used are metal or organic, so they will not fuse even if the board is small or thin.

7. Easy transportation: The board is very lightweight, and it is easy to transport in a small volume.

8. Multilayer implementation: It is easy to design multilayer PCBs because of the thin size.

9. Easy to fabricate: The board has various processing methods such as Drilling, Routing, Etching, and Soldering, making it easier to complete the production process. In addition, it can meet different customer needs from prototype to mass production.

10. The product is much cheaper than inorganic materials such as glass or ceramics.

11. The solderability is excellent; the components can be soldered with little heat, and the processing time is reduced.

Key Applications

The 3mm PCB was originally created for a very specific purpose, which is to create boards that can fit in your wallet. However, there are many other applications for this size of the board, including:

Motorized wheelchairs and scooters

Robotic arms and hands

Household appliances

Wireless cameras and security systems

Portable game machines and media players, such as MP3 players

Some of them are used for unmanned aircraft vehicles

Several of these applications make use of wireless connectivity. It should be noted that the 3mm design is much more compatible with wireless connectivity than 1inch designs. For example, if you were to design a 3mm board for your project, there is a good chance that you could integrate Bluetooth functionality into your board.


Size is not required for the size of the project. Many professional and home users are already using the 1-inch e-board for their projects in their smartphones using Bluetooth or Wi-Fi. Many of them also use smaller e-boards in their projects and even smaller sizes like .5 or 1 mm in their projects.

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