1. Three factors that need to be considered in the design of electronic products
Climate environment, mechanical environment, electrical environment.
2. What is EMC?
EMC (Electro Magnetic Compatibility), that is, electromagnetic compatibility, refers to the ability of a device or system to operate in compliance with the requirements in its electromagnetic environment and not produce intolerable electromagnetic interference to any device in its environment. Popular refers to the clutter generated by various reasons in the electrical circuit. These clutters not only hinder the normal operation of the electrical circuit, but also have a certain degree of harm to the human body. Therefore, various countries (especially the European Union) have various Provisions, both electromagnetic compatibility. The two requirements and three elements of EMC (1) The electromagnetic interference generated by the equipment to the environment during normal operation cannot exceed a certain limit. (EMI electromagnetic shielding material) (2) The equipment has a certain degree of immunity to electromagnetic interference in all environments, that is, electromagnetic sensitivity. (EMS)
Three, EMC pain points
EMC problems exist in all electronic products
The EMC form of my country's electronic products is severe and develops rapidly. EMC is a multidisciplinary technology, including: basic theories of electromagnetic fields, basic theories of radio technology, microwave technology, microelectronics technology, computer technology, communication and network technology, and new material technology.
Four, EMC solutions
How to solve the electromagnetic radiation problem of our electronic products?
(1) In response to the two requirements of EMC, the engineering solutions are also based on the characteristics of each aspect: (1) Improve the circuit design of electronic equipment, adopt separate layout of filter parts and components with different characteristics (partially increase shielding cover , Paste metal foil, also use metal woven mesh, etc.)
(2) Spraying conductive paint, plating a layer of conductive metal foil, and adding electromagnetic wave absorbing materials around the circuits and devices with high electromagnetic wave emission capability in the entire electronic equipment casing.
(3) Various occasions from small hand-held devices to large-scale shielded rooms, where there is sliding friction, can be better used for shielding materials placed on the top or side of the shielding body, the capacity and closing pressure are limited, and good conditions are required. Suitable high-performance shielding occasions, use shielding beryllium copper reeds, conductive foam and other materials.
(4) Apply FIP (Form-In-Place) points in small and complex electronic communication equipment, such as mobile phones, tablet computers, base station filters, radio frequency modules, automotive central control systems, etc., in all environments that produce electromagnetic interference Glue technology.
(5) SMT stickers should be applied to the signal lines or grounding lines of TV, mobile phones, tablets, cameras, navigation, MP3, monitors and other products that need to solve the problems of EMI electromagnetic shielding material grounding, electrical connection, mechanical buffering, etc., where the design space is small Pieces of foam.
Five, the development trend of electromagnetic shielding materials
Optimize the material structure, improve the molding process, and use new technology (such as nanotechnology, amorphous technology, etc.) to prepare electromagnetic shielding materials with better electromagnetic shielding performance:
Adopt green technology and composite technology to develop low-cost, pollution-free, low-density, high-performance new materials that adapt to the needs of complex electromagnetic environments;
The combination of functionalization and structuralization can not only realize the electromagnetic shielding function, but also realize the shielding material with "intelligent" characteristics for the load-bearing engineering structure.