PCB (printed circuit board) design refers to the design of printed circuit boards. The design of the printed circuit board is based on the circuit schematic diagram to realize the functions required by the circuit designer. The design of the printed circuit board mainly refers to the layout design, which needs to consider various factors such as the layout of external connections, the optimal layout of internal electronic components, the optimal layout of metal connections and through holes, electromagnetic protection, and heat dissipation. Simple layout design can be realized by hand, and complex layout design needs to be realized by computer-aided design (CAD). Excellent layout design can save production costs and achieve good circuit performance and heat dissipation performance.