How to Prevent Your PCB from Overheating
The materials used in PCBs (printed circuit boards) are designed to withstand a certain amount of heat. However, poor design layouts can lead to overheating and when this happens, it can lead to inefficiencies in the design, or the design failing to work as intended. Because of this, heat management is often seen as being a PCB designer’s number one priority. But how can you prevent your PCB from overheating? Let’s take a look.
Consider Heat Pipe Integration
If you’re creating a small electronic device, such as a cell phone, heat pipe integration could be the best solution for your design. Including a reliable, passive heat transfer pipe will ensure you have no moving parts, while also providing you with vibration free operation and effective thermal conductivity. How this works is that the pipe contains a small amount of liquid – which can be ammonia, sodium, acetone, nitrogen or water. This fluid absorbs the heat and turns into vapor. The vapor then moves further down the pipe and returns to fluid where it can operate again as intended when required. It’s a cost-effective solution and ideal for small devices.
Use Thermal Interface Materials
Thermal Interface Materials (TIMs) contain a substance, usually thermal gasses, that offers better thermal conductivity than air. They are placed within parts of the PCB design where air is usually located in order to provide a better level of heat conductivity. They work really well as they tend to be about 100 times more effective than the heat that they displace. A cheap professional PCB design software such as Altium can help you determine where to include these within the design for optimum success.
Active Cooling Integration: In Other Words, Add a Fan
Just because you’re designing a small, compact piece of kit, this doesn’t mean that you can’t integrate a fan within your design. Micro-fans are a cost effective and easy way of cooling any device, and many designers regularly use them, believing them to be the best option no matter what it is they are designing. One thing that many designers worry about is the noise of the fan. Though trust us, you don’t need to worry. The noise that is generated will be determined by the size of the fan, with those that are larger and move faster generating more noise. Fans can be altered, too, and you can always add rubber or another sound dampening material if this gives you cause for concern.
Increasing Copper Width
Finally, if all of the above options are out of the question, you do have one other option. Most PCB designs use around one ounce of copper per each square foot of the design. However, if you are finding that your design is overheating, you can increase the width of the copper to three or four ounces per square foot. Copper is a heat resistant material and can massively help reduce the amount of power that is lost to overheating.
Keep the above ideas in mind the next time you are struggling with overheating in your PCB design.