PCBs used in the past were very simple and often limited to a single layer. The current use of PCB is basically very complex, these complex PCB collectively referred to as multilayer pcb fabrication, which is electronic information technology to high-speed, multi-functional, high-capacity, small volume, thin, lightweight development of the product, multi-layer PCB has become the core component of complex electronic circuits.

For the production of PCB, the higher the level, the more processes it produces, the higher the failure rate, the corresponding cost is also higher. Today I will take the four-layer board as an example to explain what these layers are called.

The four layers of a PCB board are the signal layer (top), the signal layer (bottom), the power layer (middle) PCB factory and the ground layer (middle).

Usually in circuit boards, components are usually placed on the top layer, so the top layer is also called the component side; the bottom layer is usually used for soldering, so the bottom layer is also called the soldering side. But for SMD components, both the top and bottom layers can hold components.

The structural layout of each layer of a four-layer PCB board:

1. the first layer of the middle copper tape with multiple GND outlets, you can take a small amount of wire, but do not separate each store, while the second layer of the middle copper tape VCC with multiple power outlets, you can take a small amount of wire, but do not separate each store.

2. There are four wire layers, usually the top layer, the bottom layer of the bottom layer, VCC and GND. In general, through holes, buried holes and blind holes are connected to each other, more than double PCB buried holes and blind holes. In addition, the VCC and GND layers try not to take signal lines.

Main advantages of multilayer PCBs.

Small size: Small size can make us these PCBs very important because the size of information technology and electrical and electronic control equipment development is getting smaller and smaller. Layered PCB's are designed to teach smaller sizes for the management of electronics and electronic system devices such as computers, smart through cell phones, tablets, wearables and laptops.

Boring assembly: As mentioned above, the dimensions of 4-layer and higher PCBs are smaller, so they favor contemporary gadgets.

Quality:One of the key features of this PCB is its quality as the planning is in its creation. These printed circuit boards are very effective and have no issues throughout their lifespan.

Durability: The layers of PCBs are durable as they can withstand not only weight but also high temperatures. There is always an insulating layer between the different layers of these PCBs to prevent damage.

Flexible design: Nowadays these PCBs are available in flexible design but not all multilayer PCBs are flexible. Flexible 4-layer PCBs or higher can be very useful if a slight bend is required. However, all of these PCBs are not flexible.

Power: These PCBs have a high density between these components and are comprised of different layers made into a single layer PCB. The adjacent areas of these states enable the circuit board design to be able to connect through additionally, the electrical engineering properties of these PCBs enable them to develop with greater power impact.

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