Power adapters have been widely used in various electronic devices, and they generate a large amount of heat during operation. If these heat cannot be discharged in a timely manner and kept at a reasonable level, it will affect the normal operation of power adapters. To improve the reliability of power adapter operation, thermal design is an essential and important part of power adapter design.

1. On the premise of ensuring heat dissipation requirements, try to choose small and lightweight heat sinks.

2. During installation, try to increase the contact area and pressure between the device and the heat sink, and apply silicone grease to the contact surface. Pay attention to the installation method and direction.

3. The surface of the heat sink should be rough, but the contact surface with the device should have good smoothness and be painted black.

When insulating the pipes from the casing, the radiator should be insulated from the casing, not only using electrical insulation sheets.

5. In a sealed situation, be careful not to have convection. 6. Air duct design during air cooling.

While minimizing the heat generated by power switches through optimization design, it is also necessary to utilize the heat transfer principles of conduction, convection, and radiation through heat sinks to quickly release the heat generated by the components into the surrounding environment, reducing internal heat accumulation and lowering the operating temperature of the components. This is known as thermal design. The basic principles of thermal design are as follows.

(1) It is necessary to have a clear understanding of the working environment of the power adapter, including the range of environmental temperature changes, the radiation from the sun or other surrounding objects, etc. The heat dissipation scheme of the power adapter should meet the requirements of the application environment.

(2) For components that use Level II derating, the maximum allowable temperature can be determined based on the data of the components.

(3) The thermal design of power adapters should be considered simultaneously with industrial design, electrical design, structural design, reliability design, and electromagnetic compatibility design. While ensuring electrical performance and reliability requirements, a balanced analysis should be conducted to achieve a compromise solution. For example, when designing ventilation mesh panels, it is generally desirable to have a high opening rate, which involves the spacing and size of the holes. From the size of the hole, of course, the larger the better, but on the one hand, considering the requirements of electromagnetic compatibility, the diameter of the hole generally does not exceed 1/20 of the interference wavelength; On the other hand, according to safety regulations, the opening of the system must meet any of the following requirements. ① The size of the hole should not exceed 5mm when measured in any direction If the width of the hole is within 1mm, the length is not limited The size of the hole is not limited, but it must be ensured that external objects do not directly fall into the hole and touch parts with dangerous voltage.

(4) To ensure that the cooling system has a simple structure, reliable operation, and low cost. An important principle is to strive to design highly reliable products using mature processes and technologies.

(5) Consider the vibration and noise of the cooling equipment.

(6) If forced air cooling is used, the inlet temperature of the cooling air must be limited. Even if the inlet of the cooling air is far away from the outlet of other equipment's hot air, it cannot be reused for cooling.