There are many reasons for PCB overheating. In general, if design defects, proper parts and materials are not selected, misplaced components and poor heat dissipation may cause excessive heat on the printed circuit board (PCB).
In integrated circuits, excessively high temperatures can negatively affect functions, components, and the circuit board itself. The impact of high temperature is negligible in many applications, but in high-performance designs, the impact can be significant.
Therefore, proper control of heat is an important step in electrical engineering. To manage heat well, this involves everything from the component level to the physical board system and operating environment. Below, the SysPCB - Shenzhen PCBA manufacturer will further introduce some of the main reasons for the overheating of the circuit board.
1. Improper component placement
Some high-power equipment needs to reserve natural ventilation or forced ventilation to dissipate heat.
If there is no proper airflow to dissipate heat, the PCB will accumulate most of the heat, causing the temperature to gradually increase, resulting in reduced or damaged circuit performance. In addition, it should be noted that sensitive components should not be placed near components that emit large amounts of heat.
High-power components such as power transistors generate a lot of heat on the PCB. However, with proper heat dissipation and natural cooling or forced cooling, the temperature can be kept within a safe range.
2. Environmental and external thermal factors
When the PCB is used in an extreme temperature environment, during the design process, if the temperature conditions in the target environment are not considered, the electronic components may be subjected to excessive pressure.
Generally, electronic component manufacturers will provide specifications that are applicable within a specific temperature range. For example, the resistance value is usually at a temperature of 20°C. It is worth noting that the parameters of components such as resistors, capacitors, and semiconductors change with temperature.
3. Wrong selection of parts and materials
During the selection of electronic component materials, failure to follow the recommended guidelines may cause heat dissipation. When selecting materials for electronic components, it is important to review detailed data and consider all relevant information related to power consumption, thermal resistance, temperature limits, and cooling technology.
In addition, make sure to select the power rating appropriate for the application. An easy mistake is to use the same resistor repeatedly (probably because the corresponding component is already in your CAD library), although some applications may require higher power ratings. Perform a fast power calculation on the resistor and ensure that its rating is significantly higher than the maximum expected loss.
Another important issue is the choice of PCB dielectric materials. The printed circuit board itself must be able to withstand the worst-case thermal conditions.
4. Defects in PCB design and manufacturing
Poor layout and manufacturing processes can cause PCB thermal problems. Improper soldering may hinder heat dissipation, and insufficient trace width or copper area will cause the temperature to rise.
To prevent heat dissipation, designers must reduce heat dissipation and use other cooling techniques when natural cooling is insufficient. Thermal optimization design requires attention to component specifications, PCB layout, PCB dielectric materials and environmental conditions.