With businesses opting for network expansions and high-speed connectivity, the communication equipment such as routers, switches, and other connected devices need to be compatible with high-frequency signals and probable electromagnetic interference (EMI). While it is important to shield or suppress EMI using various methods, the devices need to be EMC-enabled or electromagnetically compatible. Also, the PCB assemblies in these devices require shielding as well. This is because there are several components mounted on the boards, some of which may produce EMI. Also, there are EMI-sensitive and analog components which may be impacted due to EMI. So, PCB EMI shields play a significant role in suppressing internal and board-level EMI as well as protecting the devices from external noise. This post discusses why good-quality and efficient board-level shields are important in communication equipment.
Why Use Board Level EMI Shields in Communication Equipment?
Most of the devices today are designed to be electromagnetically compatible, which means they can function normally in the presence of EMI. However, at times, EMI in large amounts can cause the device to malfunction, and this may come from internal or board-level components. Hence, board level shielding is necessary. Here are some reasons why it is recommended to use board-level EMI shields in PCBAs of communication devices such as switches, routers, and more.
- Design Complexities: The multiple functionalities of devices such as routers, switches, hubs, modems, cameras, IP phones, and many others make their design complex. This leads to a complex PCB architecture, especially in high-frequency applications.
- Miniature Size: The size of devices is decreasing by the day, and this trend is expected to continue over the next few years. This creates a demand for compact size boards with several components, layers, and vias. Too many components placed on a small-sized board may lead to internal EMI. EMI shields can be custom made to fit the small size and exact dimensions of the board.
- Component Isolation: It is important to isolate components that are EMI sensitive as well as ones that generate EMI or RFI. Isolating such components prevents them from EMI exposure and subsequent damage, which can be done using customized EMI shields.
Conclusion
Achieving immunity against EMI is crucial for communication equipment and even small network devices. This is considering the increasing complexities in their design, increased number of components, limited space, and hence the probability of EMI signals clashing. While devices are designed to be EMC compatible, EMI suppression or filtration should also be one of the measures taken. Metal plated plastic EMI shields prevent unwanted signals and subsequent damage to the board and in turn the device. It is best to use lightweight and flexible shields that fit well on the board and cover the required areas. XGR Technologies offers SnapShot® EMI shields made from a thin polyetherimide film on the interior and conductive tin on the exterior surfaces. These are flexible and lightweight shields that help reduce electromagnetic inference. If you need further information on these EMI shields and their application in network devices, you can contact the team at XGR Technologies via phone or email.
