With the arrival of 5G and the improvement of the signal rate requirements for big data servers, the requirements for data switches in cloud computing centers are also becoming higher and higher. The PCB material level is a higher level than the server material, and the requirements for insertion loss are more strictly controlled.
The design will generally be 12 layers or more, the thickness to diameter ratio of PCB is above 9:1, the corresponding line density is at least 0.075/0.100mm, the minimum aperture is processed with 0.225mm aperture, and there will be mixed pressure design. The main mixed pressure material is generally Ultra Low Loss grade material mixed with ordinary FR4 to reduce costs. Its main signal operating frequency is above 10GHz, belonging to the operating range of higher frequency, so this type of product will have more optical modules or high-speed connector interfaces on the PCB layout. At the same time, because of the high insertion loss requirements of the signal, there will be more back drilling design and resin plug hole+POFV design.