PCB (Printed Circuit Board), the Chinese name is printed circuit board, also known as printed circuit board, printed circuit board, is an important electronic component, is the support of electronic components, and is the provider of electrical connections for electronic components. Because it is made by electronic printing, it is called a "printed" circuit board.

　　The role and function of PCB in various electronic devices

　　 1. Pad: Provide mechanical support for fixing and assembling various electronic components such as integrated circuits.

　　 2. Wiring: Realize wiring and electrical connection (signal transmission) or electrical insulation between various electronic components such as integrated circuits. Provide the required electrical characteristics, such as characteristic impedance.

　　3. Green oil and silk screen: Provide solder mask graphics for automatic assembly, and provide identification characters and graphics for component insertion, inspection, and maintenance.