We all know that electronic equipment will generate a certain amount of heat when it is working. If the PCB board is kept at a high temperature, the components on the PCB board may fail due to overheating. Therefore, we must attach great importance to the heat dissipation of the PCB board. What are the heat dissipation methods of PCB board?
How does the PCB board dissipate heat?
1. Heat dissipation through the PCB itself
Commonly used PCB boards include copper clad, epoxy glass cloth or phenolic resin glass cloth. Although these substrates have excellent electrical and processing properties, they suffer from poor heat dissipation. Therefore, the way to solve the heat dissipation problem is to improve the heat dissipation capacity of the PCB that is in direct contact with the heating element, and transmit or dissipate it through the PCB board.
2. High heating device with radiator and heat conduction plate
When there are a small number of components on the PCB, the heat output is relatively large (less than 3), and heat sinks or heat pipes can be installed on the heating components. When the temperature cannot be lowered, a radiator with a fan can be used to enhance the cooling effect. When there are many heating devices (more than 3), large heat sinks can be used.
3. Use reasonable wiring design to realize heat dissipation
Since the thermal conductivity of the resin in the PCB is poor, and the circuits and holes of the copper foil are good conductors of heat, increasing the residual rate of the copper foil and increasing the heat conduction holes are the main means of heat dissipation.
4. Arrange the components according to the heat dissipation method
Components on the same PCB should be arranged as far as possible according to their heat generation and heat dissipation. Devices with small calorific value or poor heat resistance (such as small signal transistors, small-scale integrated circuits, etc.) should be placed upstream (inlet) of the cooling airflow, and devices with high heat generation or good heat dissipation should be placed upstream (inlet) of the cooling airflow. Resistors (such as power transistors, LSI, etc.) should be placed downstream of the cooling airflow.
5. Avoid hot spots on the PCB
In order to maintain the uniformity and uniformity of the PCB surface temperature performance, the components with high power should be distributed on the PCB as evenly as possible. However, it is difficult to achieve strict uniform distribution during the design process, but it is necessary to avoid areas with high power density to avoid hot spots that affect the normal operation of the entire circuit.