How to design PCB heat dissipation and cooling?

For electronic equipment, a certain amount of heat is generated during operation, so that the internal temperature of the equipment rises rapidly. If the heat is not dissipated in time, the equipment will continue to heat up, and the device will fail due to overheating. The reliability of the electronic equipment Performance will decrease. Therefore, it is very important to conduct a good heat dissipation treatment on the circuit board.


PCB design is a downstream process that follows the principle design, and the quality of the design directly affects the product performance and the market cycle. We know that the components on the PCB board have their own working environment temperature range. If this range is exceeded, the working efficiency of the device will be greatly reduced or failure, resulting in damage to the device. Therefore, heat dissipation is an important consideration in PCB design.

So, as a PCB design engineer, how should we conduct heat dissipation?

The heat dissipation of the PCB is related to the selection of the board, the selection of the components, and the layout of the components. Among them, the layout plays a pivotal role in PCB heat dissipation and is a key part of PCB heat dissipation design. When making layouts, engineers need to consider the following aspects:

(1) Centrally design and install components with high heat generation and large radiation on another PCB board, so as to conduct separate centralized ventilation and cooling to avoid mutual interference with the motherboard;

(2) The heat capacity of the PCB board is evenly distributed. Do not place high-power components in a concentrated manner. If it is unavoidable, place short components upstream of the airflow and ensure sufficient cooling air flow through the heat-consumption concentrated area;

(3) Make the heat transfer path as short as possible;

(4) Make the heat transfer cross section as large as possible;

(5) The layout of components should take into account the influence of heat radiation on surrounding parts. Heat sensitive parts and components (including semiconductor devices) should be kept away from heat sources or isolated;

(6) Pay attention to the same direction of forced ventilation and natural ventilation;

(7) The additional sub-boards and device air ducts are in the same direction as the ventilation;

(8) As far as possible, make the intake and exhaust have a sufficient distance;

(9) The heating device should be placed above the product as much as possible, and should be placed on the air flow channel when conditions permit;

(10) Do not place components with high heat or high current on the corners and edges of the PCB board. Install a heat sink as much as possible, keep it away from other components, and ensure that the heat dissipation channel is unobstructed.