The circuit board is a very common and important part for us. It exists in almost every kind of electronic equipment around us. There are various components installed on it. The electrical circuit is connected through wires, bonding pads and metallized holes. In order to facilitate identification, the PCB manufacturer also prints a screen diagram on it, which makes it easier to identify various components.

How to identify components on PCB processing plant materials? The components on the PCB board are as shown in the figure below. There are two main categories. One is through-hole type, which is relatively large and can only be inserted after drilling holes on the board. The other category is surface mount type, which does not need to drill holes. It uses a steel mold to place semi molten solder paste on the circuit board, paste SMD components, and solder them on the circuit board by reflow soldering.

2. Understand the wires, vias and pads on the PCB

The wire on the board made by the PCB manufacturer is called copper film wire, which is used to connect the lines on the circuit board. Generally, the printed wire is the connection between two pads or vias. Many pads are actually the pins on the components. When two pads cannot be connected, they will be connected through jumpers or vias. The vias are also called metallized holes, which are used to connect the wires between different layers.

In the production of batch circuit boards, a layer of solder mask will be laid on the board. The color of solder mask is generally green or brown, so the reason why the PCB of PCB processing board is generally green or brown is actually the color of solder mask on it.

In addition to other places to be welded on the circuit board, the solder mask is usually added with a layer of solder mask, which can weld quickly and prevent short circuit caused by solder overflow. The places to be welded on the pad need to be coated with flux to facilitate welding.