The communication backplane PCB is made of isola 370hr material. The communication backplane bus is a high-speed data path between the PLC host and the I / O expansion module, supporting the I / O data refresh between the host and the expansion module. The technical level of backplane bus determines the I / O expansion ability of PLC products, which is the core technology of PLC design and manufacturing. At present, the PCB board of PLC mostly uses isola 370hr material, and PLC mostly uses serial communication technology to realize backplane bus. Compared with parallel bus, serial bus has less leads and low hardware cost, and is not easy to be interfered. Serial bus can improve the reliability of automatic equipment in harsh factory and industrial environment. In the field of communication PCB, it is widely used in wireless network, transmission network, data communication and fixed network broadband. Related products include backplane, high-speed multilayer board, high-frequency microwave board, multi-functional metal substrate, etc.