PCB designers should pay attention to the following points to ensure proper cooling of electronic devices:
1) Use high temperature components as much as possible;
2) Separate temperature sensitive components from high heat dissipation sources;
3) To ensure proper conductor cooling, cooling can be achieved through the following three heat transfer methods, such as heat conduction, convection and radiation.
Heat conduction cooling is achieved through the following ways:
1) Use materials with high thermal conductivity;
2) Use the shortest distance to the radiator;
3) Ensure a good thermal connection between the various parts of the conduction path;
4) Install printed conductors as large as possible in the path of heat propagation.
Convective cooling can be achieved by:
1) Increased surface area for heat to spread;
2) Use turbulent flow instead of laminar flow to increase heat transfer efficiency and ensure that the surrounding environment of the required cooling part is well cleaned.
Increased radiation cooling can be used:
1) Use materials with high emission and absorption;
2) Increase the temperature of the radiator;
3) Reduce the temperature of the absorber;
4) Minimize the reflection of the radiator itself through geometric PCB design. Special care must be taken in the layout of power transistors or high-power resistors in order to eliminate localized hot spots that could damage the board or adjacent components. Generally, these components should be installed near the frame of the heat sink.
In order to keep the components below the maximum operating temperature, also do:
1) Analyze the circuit to understand the maximum power consumption of each component;
2) Determine the desired maximum surface operating temperature of the component, the maximum allowable temperature depends on the component itself