APPLICATION AND SOLUTION OF THERMAL SILICA PAD IN WIRELESS CHARGER

Wireless charging technology breaks through the traditional connection line charging, which is a wireless charging technology using intelligent power transmission, improving the charging efficiency and convenience. In 2017, after the mobile wireless charging was widely recognized, its usage rate is also increasing. It is the explosive product of mobile phone charging industry. Because of its small size, the working temperature of the internal electronic components needs to be solved first, and the heat conduction silica gel sheet provides its heat dissipation scheme to solve this problem.

The surface of thermal conductive silicon pad has certain flexibility, excellent insulation, compressibility and natural viscosity. It is designed for the use of slot heat transfer design and production. It can fill the gap, complete the heat transfer between the heating part and the cooling part, and also play the role of insulation, damping, sealing and so on. It can meet the design requirements of miniaturization of equipment. It has manufacturability and practicability, and its thickness is widely used. It is a good heat conducting material, widely used in electronic and electrical products. Silicone thermal pad is a kind of heat conducting medium, which is used to transfer the surface temperature of heat source to radiator or air. In order to achieve better heat dissipation efficiency, the wireless charging base is generally made of metal materials and integrated with effective anti-skid pad, which lays a good foundation for the heat dissipation of internal electronic components and achieves the effect of anti-skid and wear-resistant.

In the inner coil of wireless charging, the heat is also concentrated in the middle. Therefore, the main temperature probe will be installed in the middle of the coil to ensure that the charger's operating temperature is within the stable temperature range. When the screws of the coil metal base plate are removed, the internal structure of the product's bottom shell can be seen. The bottom shell is made of metal, which is also the key to heat dissipation. Metal is used to better transmit the heat inside the product to the outside through the bottom shell, so that the internal working temperature is always in a stable state, so as to extend the service life of the product. However, due to the connection between the bottom shell and the wireless charging circuit board, all components are concentrated on one side of the printed circuit board. Because the circuit board is an irregular whole and has no direct seamless connection with the bottom shell, the bottom shell is pasted with thermal silicon pad to fill the gap between the bottom shell and the circuit board. Thus, the heat of the circuit board is transmitted to the bottom shell through the heat-conducting silicon film for heat dissipation, and also plays the role of electromagnetic shielding.