The upgrade of hardware components, and the exponential increase in the number of networking devices and antennas in 5G era have put forward new requirements and challenges for related materials in the industry chain.
Electromagnetic interference can be easily discovered between devices and within the devices themselves. Besides, the harm of electromagnetic interference and electromagnetic radiation also become more and more serious. Meanwhile, with the upgrading of electronics, the power consumption of equipment continues to increase, and the heat emission issue becomes critical.
In the future, the bottleneck of high-frequency and high-power electronic products is the electromagnetic radiation and heat generated by them. In order to solve it, more and more electromagnetic shielding and heat-conducting components will be considered during designing of electronic products. Therefore, the role of electromagnetic shielding and heat dissipation materials and devices will become necessary, and the demand will continue to grow significantly.
Electromagnetic interference shielding(EMI shielding)
Introduction
After the electronic equipment is energized and started, the internal current generates electromagnetic waves, which will interfere with the signal reception and transmission of other surrounding electronic equipment. Even worse, it enables to interrupt the normal work of other electronic devices.
EMI shielding products use EMI shielding materials to reflect and absorb electromagnetic waves. By blocking the propagation path of electromagnetic waves to achieve isolation and shielding of electromagnetic waves.
Due to the discontinuity of impedance at the interface between air and shielding materials, incident waves will be reflected back. And part of the electromagnetic waves entering the shielding material body will be attenuated and absorbed by the shielding material.
Two ways for electromagnetic interference
There are mainly two methods for EMI shielding of electronic equipment. One is the structural body of electronic device, which is usually made of steel plate, aluminum plate, copper plate or metal plating, conductive coating, etc.
The other is the shielding gasket, which is a conductive EMI shielding product. It is specially used to solve the problem of electromagnetic shielding in the gaps of the structural body. Generally, it is processed from materials such as metal, plastic, silicone and cloth through stamping, forming and heat treatment.
EMI materials
The technical level and development route of EMI shielding components are mainly dominated by the development of electronic shielding materials. Its features like electrical conductivity, magnetic permeability and material thickness are the three basic factors of shielding effectiveness.
The demand for electromagnetic shielding materials will develop in the direction of higher shielding effectiveness, wider shielding frequency and better comprehensive performance in the future.
(1) Common electromagnetic interference shielding products
Currently, the common materials are including conductive plastic devices, conductive silicone devices, metal shielding devices, conductive cloth pad devices, and wave-absorbing devices.
Some new materials are being explored like foamed metal shielding materials, nano-shielding materials and intrinsically conductive polymer materials, relying on their own good conductivity to achieve EMI shielding function. EMI are mainly used in the communication industry, consumer electronics, and automotive electronics, medical, military and electric power and other fields.
(2)Development direction of EMI materials
The future development direction of EMI shielding materials are as follows:
- Filled materials like conductive plastic parts and silicone parts will choose more efficient and low-cost materials;
- Conductive gaskets will use thinner raw material cloth and foam with better performance;
- Conductive coatings using carbon-based conductive powder, etc.
At the same time, various types of electronic devices will be included in the EMC management standards in the future, and the EMC standards will become more stringent.
Thermally conductive factor
Thermal components are usually used to fill the air gap between heating parts and heat dissipation parts, and make good use the performance of thermal components to improve thermal conductivity capability.
By filling the rough and uneven bonding surface, replacing the non-heat-conducting air with a thermal interface material with a thermal conductivity much higher than that of air, the thermal resistance through the thermal interface is reduced, and the heat dissipation efficiency of semiconductor components is improved.
Also read: 7 tips for how to handle the PCB heat dissipation
Thermally conductive materials
At present, thermally conductive materials are mainly divided into thermally conductive paste, sheet thermally conductive gap filling material, liquid thermally conductive gap filling material, phase change thermally conductive interface material, thermally conductive gel and graphite film, etc.
Among them, thermally conductive graphite film has gradually become the preferred solution for smart electronic products. However, with the continuous development of technology, electronic products have higher requirements for thermal management solutions, so thermally conductive graphite film materials gain more attention in public. For example, thinner thickness, better thermal conductivity, and the ability to process 3D structural products, or combine with other materials to form composite multifunctional materials, etc.
EMI protection, or Electromagnetic Interference protection, refers to methods and technologies used to shield electronic devices from unwanted electromagnetic signals that can disrupt their normal operation. EMI can cause malfunctions, data loss, or degraded performance in electronic equipment. Effective EMI protection involves using shielding materials, grounding techniques, and circuit design practices to minimize interference and ensure reliable device performance.
EMI shielding and RF shielding are related but distinct concepts. EMI shielding focuses on protecting electronic devices from a broad range of electromagnetic interference, which can include various frequencies and sources. It aims to prevent interference that could affect device functionality or performance.
RF shielding, on the other hand, specifically targets radio frequency interference. This type of shielding is designed to block or reduce interference from radio frequencies, which are a subset of the broader electromagnetic spectrum. RF shielding is crucial for applications where precise control over radio frequencies is necessary, such as in communication systems or sensitive electronics.
In essence, while both types of shielding aim to protect devices from interference, EMI shielding covers a wider range of electromagnetic disruptions, whereas RF shielding focuses specifically on radio frequency issues.
The best protection against EMI (Electromagnetic Interference) involves a combination of strategies tailored to the specific needs of your equipment. Key approaches include:
Shielding: Use materials like conductive enclosures or shielding films to block external interference.
Filtering: Implement filters in power lines and signal lines to remove unwanted frequencies.
Grounding: Ensure proper grounding to provide a path for stray currents and reduce interference.
Circuit Design: Design circuits with careful layout and separation of sensitive components to minimize EMI effects.
By integrating these techniques, you can effectively safeguard your devices from EMI and maintain their optimal performance.
To protect against EMI (Electromagnetic Interference), consider these key strategies:
Shielding: Use conductive materials to enclose sensitive components and block external interference.
Filtering: Install filters in power and signal lines to remove unwanted frequencies and prevent interference from affecting your device.
Grounding: Properly ground your equipment to provide a clear path for stray electrical currents, reducing the impact of EMI.
Circuit Design: Optimize the layout of your circuits to minimize susceptibility to interference, such as by separating high-frequency and sensitive signal paths.
By combining these methods, you can effectively protect your equipment from the detrimental effects of EMI.
Shielding EMI (Electromagnetic Interference) involves using materials or enclosures to block or absorb unwanted electromagnetic signals that can disrupt electronic devices. This technique creates a barrier around sensitive components to prevent external interference from affecting their performance. Effective EMI shielding ensures that devices operate reliably by minimizing the impact of external electromagnetic disturbances.
To avoid electromagnetic interference (EMI), you can take several practical steps:
1.Use Shielding: Encase sensitive electronics in materials that block or absorb EMI to protect them from external interference.
2.Employ Filters: Install EMI filters on power and signal lines to remove unwanted frequencies and reduce interference.
3.Ensure Proper Grounding: Connect equipment to a common ground to help divert stray currents and minimize interference.
4.Optimize Circuit Design: Design circuits with careful layout to separate high-frequency signals from sensitive components, reducing the chance of interference.
5.Maintain Distance: Place sensitive equipment away from strong sources of EMI, such as motors or wireless transmitters, to reduce the impact.
Last updated on August 26th, 2024 at 03:29 am