PCB (Printed Circuit Board) is an integral part of electronic products. It carries electronic components and provides electrical connections. The internal structure of PCB is composed of multi-layer circuit boards, each layer has specific functions and structures.
First of all, the internal structure of PCB includes base material, conductive layer, insulating layer and pad. The base material is the main body of the PCB, usually made of fiberglass reinforced plastic (FR-4), which has good mechanical strength and insulation properties. The conductive layer is made of copper foil covering the surface of the substrate and is used to conduct current and signals. The insulating layer is a piece of material placed above and below the conductive layer to isolate
circuits between the same layers. Solder pads are metal discs used to connect electronic components, usually on the edge or surface of a PCB.
Secondly, the internal structure of PCB also includes circuit layers and circuit intervals. The circuit layer refers to the layer located between the conductive layer and the insulating layer, which contains the circuit connections of electronic components.
Depending on the complexity of the electronic product, a PCB can have single, double or multiple circuit layers. Circuit spacing refers to the insulating layer located between different circuit layers, which is used to isolate circuits on different layers to prevent short circuits and interference.
Additionally, the internal construction of the PCB includes connections via holes and pads. Vias are small holes located on PCBs that are used to connect conductive layers between different circuit layers. Through holes are usually
Filled or plated with copper to ensure a good electrical connection. Solder pads are metal discs located on the PCB that are used to connect electronic components. The pads are usually connected to electronic components through soldering technology, such as surface mount technology (SMT) or plug-in soldering technology.
Finally, the internal structure of the PCB also includes the silk screen layer and solder mask layer. The silk screen layer is a marking layer located on the surface of the PCB, used to mark the location, pins and polarity of electronic components. Silk screen layer
Usually printed with white ink to improve readability. The solder mask is an insulating layer located on the surface of the PCB to protect the circuit from the external environment and prevent short circuits and corrosion. solder mask
It is usually covered with green or red solder mask paint to provide good insulation properties.
In short, the internal structure of PCB is composed of multi-layer circuit board, conductive layer, insulating layer, pad, circuit layer, circuit spacing, via hole, silk screen layer and solder mask layer. These components cooperate with each other to form a complete circuit board, which provides reliable electrical connection and protection for the normal operation of electronic products. With the continuous development of electronic technology, the internal structure of PCB is also constantly innovated and improved to meet higher performance and reliability requirements.