Thermal interference and resistance of advanced PCB design

Thermal interference is an important factor that must be eliminated in PCB design. It is assumed that the components and components have a certain degree of heat during operation, especially the heat emitted by the more powerful components will interfere with the surrounding temperature-sensitive components. If the thermal interference is not well suppressed, then the entire circuit The electrical properties will change.

In order to suppress thermal interference, the following measures can be taken:

(1) Placement of heating element

Do not place it on the board, it can be moved outside the case, or it can be designed as a separate functional unit, placed near the edge where it is easy to dissipate heat. For example, a microcomputer power supply, a power amplifier tube attached to the outside of the case, etc. In addition, devices with a large amount of heat and devices with a small amount of heat should be placed separately.

(2) Placement of high-power devices

should be arranged as close to the edge as possible when the printed board, and should be arranged above the printed board as much as possible in the vertical direction.

(3) Placement of temperature sensitive devices

The temperature-sensitive device should be placed in the lowest temperature area. Never place it directly above the heating device.

(4) Arrangement and airflow of devices

No specific requirements. Generally, the inside of the equipment uses free convection to dissipate heat, so the components should be arranged vertically; if the heat is forced to dissipate, the components can be arranged horizontally. In addition, in order to improve the heat dissipation effect, components that have nothing to do with the circuit principle can be added to guide heat convection.