Electronic equipment must dissipate heat during operation. Therefore, when planning the schematic diagram of the PCB circuit, thermal planning must be carefully considered; once the planning is improper, it will adversely affect the reliability of the electronic equipment. So, what rules should be followed for PCB thermal planning?

1. From the point of view of being conducive to heat dissipation, the PCB circuit board should be installed upright, and the distance between the boards should not be less than 2cm.

2. For equipment that uses free convection air cooling, the integrated circuits should be placed vertically; for equipment that uses forced air cooling, the integrated circuits should be placed horizontally.

3. The equipment on the same PCB circuit board should be placed as far as possible according to its calorific value and degree of heat dissipation: equipment with low calorific value or poor heat resistance (such as small-signal transistors, etc.) should be placed upstream of the cooling airflow; Large or heat-resistant equipment (such as power transistors, etc.) is placed under the cooling airflow Z. Multilayer circuit board

4. In the horizontal direction, the high-power equipment should be placed as close as possible to the edge of the PCB circuit board to shorten the heat transfer path; in the vertical direction, the high-power equipment should be placed as close as possible to the top of the PCB circuit board, so as to reduce the temperature of the equipment that makes it difficult for other equipment. influences.

5. Equipment that is more sensitive to temperature should be placed in an area with very low temperature (such as the bottom of the equipment), and multiple equipment should be staggered on the horizontal plane.

6. When planning, study the air movement path, reasonably equip equipment or printed circuit boards; avoid leaving a large airspace in a certain area.

7. Many practices have shown that the temperature of the printed circuit can be effectively reduced by choosing a reasonable equipment placement method.