What are the technical requirements for 5G PCB boardsPosted on 2020-01-09
With the rapid development and progress of the times, communication technology and communication products have also made great achievements and progress. With the advent of 5G PCB boards technology and products, the requirements of the communication industry for PCB boards are also constantly increasing. As a very important electronic component in communication products, the development of the PCB board industry will also face new challenges. In order to adapt to the development of 5G PCB board technology, the performance and technical requirements of PCB board will also put forward higher requirements and standards. This article will briefly introduce the PCB sheet and industry characteristics, briefly explain the application of PCB in the communication industry in the 5G era, and finally make a brief analysis of the technical requirements of 5G products for the PCB board. I hope to bring some help and inspiration to relevant practitioners.
Keywords: 5G products; PCB sheet; Technical requirements
1、Overview of PCB sheet
PCB is a printed circuit board. As an important electronic component in electronic products, PCB is usually composed of a conductor and an insulating substrate, and plays a supporting and connecting role to electronic components in electronic products. The quality of PCBs has a great impact on electronic products, and different products have different requirements for PCB board technology. The PCB is usually a copper-clad laminate, and then the circuit is processed on the substrate material by chemical processing. In addition, for multi-layer PCBs, the conductive pattern layer, prepreg and thin copper foil are usually pressed together. The quality and performance of the PCB mainly depends on the material of the substrate, so whether its technical performance can meet the product requirements , Will directly affect product quality.
2、Characteristics of the PCB industry and the needs of the 5G era and 5G PCB board Industry Features
According to the different usage scenarios and functions of the PCB board industry, customized production is more adopted in production. It has specific requirements for plate thickness materials, line width and line spacing, etc., and therefore has a high degree of customization. In addition, due to its customized characteristics, it is not possible to ensure efficiency improvement while expanding the scale, and the industry structure is relatively scattered. In addition to the above two points, due to the small technical differences in the PCB board industry, it is more about cost control, so its industry profit comes more from cost control.
3、5G era needs
PCB boards are used in many areas of the communications industry, including wireless networks, transmission networks, data communications, and fixed-line broadband. With the advent of the 5G era, the communications field has placed higher requirements on PCB boards and brought new developments. Opportunity. Take the communication base station as an example. In the 4G era, a communication base station usually consists of a baseband processing unit, a single RF processing unit, and an antenna. Its public radio interface transmission volume is about 10Gbps. In the 5G era, such information transmission volume is obviously not enough Therefore, the rapid development of 5G technology will bring new changes to the structure of communication base stations, and the structure of base stations will change accordingly. 5G base stations use Massive MIMO antennas to form a new active antenna unit. The remaining baseband processing units are divided into a two-level architecture of a distribution unit and a central unit.Etc. can be counted among them. In order to meet the requirements of 5G products, the size of its core board must ensure stability and control the dimensional change within the allowable range.
4、5GPCB board resists deformation
As the products have higher requirements for PCB boards, PCBs need to improve the anti-deformation ability of PCB boards in order to achieve local hollowing, mixed pressing of boards, and large-sized thin plates. The requirements for PCB boards are flatness and toughness. PCB boards are easily deformed during the welding process, which often results in products that do not meet the required standards. With the rapid development of the communication industry, when such large-sized and small-sized PCBs encounter similar requirements as local hollowing out, the plate will easily deform and cause serious consequences. At present, many PCBs are To ensure that the cost increase will not be too high, to meet the 5G high-frequency requirements, many companies will mix special materials such as FR4 and PTEE, and there will be mismatches in mechanical properties, which will easily cause problems such as PCB deformation.
5. Stable Dk / Df
Generally speaking, the signal transmission rate and transmission quality are related to the dielectric constant (Dk) and the dielectric loss (Df). Because the signal transmission rate is inversely proportional to the square root of the dielectric constant (Dk), and the smaller the dielectric loss (Df), the signal The smaller the loss, so high-frequency and high-speed PCBs must achieve low transmission delay, low transmission loss and other requirements. It is required that the Dk of the plate is small and stable, and Df must be small. Nowadays, the demand for information transmission is also increasing, and the signal rate of communication equipment is constantly increasing. However, when the signal rate is above 5Gbps, the power transmission performance of the PCB will be affected. For example, the frequency stability of the board, the anisotropy of the PCB board, and the ambient temperature and humidity will cause a certain degree of impact. For the Dk / Df of a PCB board, in order to achieve the coverage of low-speed signals and high-speed signals on the same PCB, it is best to ensure the stability of its Dk / Df to meet the product usage requirements. Similarly, for the influence of ambient temperature and humidity, it is also necessary to ensure its stability.
6. Thermal conductivity requirements
In order to facilitate people’s daily use, electronic products are becoming thinner and thinner. When designing products, many components are more concentrated and power is increased accordingly. Therefore, the line width on the PCB is reduced, and the copper surface is reduced. As a result, its heat conduction is more difficult and the fever is serious. PCB overheating will affect the operating conditions and life of the components. Therefore, the problem of PCB heat conduction is also one of the important issues that the PCB industry needs to solve at present. The PCB overheating problem can be improved by buried copper blocks, heat dissipation vias, selecting a metal substrate, and selecting a thermally conductive plate.