EMC (electromagnetic compatibility) shielding is any method used to protect a sensitive signal from external electromagnetic signals, or preventing a stronger signal from signal from leaking out and interfering with surrounding electronics.
EMC can cover PCB elements such as IC chips and active components, or connectors and cables between PCBs.
Shielding is important because electromagnetic frequencies can affect many sensitive electronics, and can cause a wide variety of different issues from a simple hiss on a communication line, to a total disruption of a safety-critical signal.
As such it affects a diverse range of sectors, including all consumer and industrial electronics, and into critical systems for military and emergency services.
The main purpose of effective EMC Shielding is to prevent electromagnetic interference (EMI) or radio frequency interference (RFI) from impacting sensitive electronics.
This is often achieved by using a metallic screen to absorb the electromagnetic interference that is being transmitted through the air.
The shield effect is based on a principle used in a Faraday cage – the metallic screen completely surrounds either the sensitive electronics or the transmitting electronics.
The screen absorbs the transmitted signals, and causes a current within the body of the screen. This current is absorbed by a ground connection, or a virtual ground plane.
Several industries and the military use EMI and EMC testing. In aerospace, for example, EMI and EMC testing analyzes the extent of potential electrical threats to aircraft equipment.
The energy currents that pass through electronic systems can propagate electromagnetic radiation, but testing catches these problems and fortifies nearby electronics.
Electromagnetic interference occurs when external sources discharge energy toward devices. The unwelcome disturbance diminishes or prevents the use of the devices, and it can compromise in-flight stability.
In light of the undesirable consequences, EMI testing examines the possible causes and solutions to intervening currents.
Want to learn more? Tonex offers EMI/EMC Shielding Design Workshop, a 2-day course where participants learn the fundamentals of EMI and EMC in electronic systems as well as explore advanced concepts in EMI/EMC shielding design.
For more information, questions, comments, contact us.