Power supply heat conduction

The power supply is a key component that converts other forms of energy into usable power for electronic devices, and its power and volume requirements continue to increase with the miniaturization and integration of electronic products. However, high temperature can have a negative impact on high power density power supplies, including reduced performance reliability, shortened service life, and increased safety hazards. Therefore, in the power supply design, heat dissipation has become an important consideration, and the selection of appropriate thermal interface materials is the key to improve the heat dissipation efficiency of the power module.

In power adapters, common heat sources include electronic components such as MOS tubes, transformers, and transistors/diodes. In order to improve the heat dissipation efficiency inside the power supply, a thermal interface material can be used to fill the gap between the heating component and the aluminum plate radiator to achieve heat conduction. In addition, in order to improve the stability of the power supply, a thermal conductive silicone gasket can be attached to the electronic component pin surface on the back of the PCB board, which not only plays the role of insulation, buffering and puncture protection, but also solves the safety problem.

In power supply design, thermally conductive silicone insulation sheets are often used between power MOS tube packages and radiator components, such as TO-220, TO-247, TO-218 and other standard components. The MOS tube and the aluminum plate radiator are fixed together by screws, and the thermal conductive silicone insulating sheet is filled in the gap between them to achieve better thermal conductivity.

In addition, there is usually an irregular concave-convex structure inside the power supply, which requires selecting a suitable thermal interface material for potting. Potting is a common choice. It can completely wrap the transformer and fix it inside the power supply, while providing good thermal conductivity. In a specific scenario, a local potting or a whole potting manner may be selected. Local potting is suitable for large and concentrated heat generation, while overall potting is often used in outdoor power supplies to solve multiple problems such as heat dissipation, waterproofing and sealing.

Therefore, it is very important to choose the appropriate thermal interface material in power supply design, which can effectively improve the heat dissipation efficiency, enhance the stability and reliability of the power supply, and ensure the safe operation of the power supply in high temperature environment.