High density: In the design of mobile terminals, every millimeter of space saved can create huge value for terminal customers. By saving space, you can use larger, higher resolution displays, larger batteries, and more complex processors and components. High frequency and high speed: With the arrival of 5G era, the obvious change of PCB performance is high frequency and high speed. As 5G, Internet of Things and other applications will use higher frequencies, it will gradually increase from the past 3GHz to 6GHz or even 24-30GHz. Considering the high resonance frequency of 5G, it is necessary to control the impedance more strictly. If it is not formed in a very high precision form, the thin wire of 5G PCB is likely to increase the risk of signal attenuation coefficient and reduce data integrity. High heating: There are "impedance" and "dielectric loss" in PCB signal transmission. With the high frequency or high-speed digitization of the signal and the increase of high power, PCB will continue to heat up. The first phase of 5G commercial frequency band in China is mainly below 6GHz, and it will reach 24-30ghz later. With the continuous improvement of 5G transmission rate, the amount of data transmission will greatly increase. In addition, the emergence of 3D video, cloud games, wireless charging and other applications will lead to a significant increase in the heating capacity of 5G communication terminals compared with the 4G era. !page-701-574
