This article is all about Thermal design considerations for the thermal management product.
You will learn the step-by-step process of design considerations for the thermal management product.
The first step is to identify the heat sources. The second step is to calculate the amount of heat that needs to be removed. The third step is to determine the type of cooling needed. The fourth step is to select a thermal interface material. The fifth step is to select a heatsink. The sixth step is to mount the heatsink to the thermal interface material.
Identify heat sources:
The first step is to identify the heat sources. There are many considerations when identifying heat sources. Some of these considerations are the type of device, the power consumption, and the operating environment.
Some of the different types of devices are processor modules, memory modules, power supply units (PSU), and circuit boards among others.
The amount of heat that is generated by each component depends on its speed, size, and the devices that are used with it.
For example, if you place three fans onto a device with one watt each you have a total of three watts. A good rule of thumb is that one watt will generate about two degrees Celsius for every watt per square centimeter.
Calculate the amount of heat that needs to be removed:
The next step in the design considerations process is to calculate the amount of heat that needs to be removed. To do this you need to know the value of q that is produced by each heat source, which is P x A x ΔT.
P = power in watts A = area in cm squared ΔT = temperature rise above ambient or room temperature
For this type of calculation, you can use a thermal resistance table to determine the thickness needed for your heatsink.
Once you have the thickness of your heatsink, you can use a thermal resistance calculator to determine the surface area.
Determine the type of cooling needed:
The next step in the design considerations process is to determine the proper type of cooling needed for each heat source. There are many different types of cooling such as Peltier cooling, vapor chamber cooling, and conduction cooling.
Each type of cooling has its own advantages and disadvantages. Peltier cooling is good for small devices with low power consumption. Vapor chamber cooling is good for removing large amounts of heat quickly. Conduction cooling is best for removing heat from a large area.
Select a thermal interface material:
The next step in the design considerations process is to select a thermal interface material. A thermal interface material serves three different purposes. The first purpose is to fill gaps between devices so that heat can be conducted more efficiently across all surfaces. The second purpose is to provide a uniform layer of high conductivity material between two close objects, such as a heatsink and processor. The third purpose of thermal interface material is that it can reduce the coefficient of thermal expansion, which allows parts to be put together without breaking.
Thermal interface materials are manufactured in different forms including grease, paste, gel (thermal grease), and tape (thermally conductive pad). Each form has its own advantages and disadvantages.
Select a heatsink:
The next step in the design considerations process is to select a heatsink. The type of heatsink that you need depends on the type of cooling that you have selected. For example, if you are using peltier cooling then you will need a small heatsink that can fit onto the device.
The size of the heatsink also depends on the power that is being dissipated by the device. The larger the heatsink, the more power it can dissipate.
Mount the heatsink to the thermal interface material:
The last step in the design considerations process is to mount the heatsink to the thermal interface material. This is done by applying thermal paste to the device and then mounting the heatsink onto it. You should always mount a heatsink before you install or remove a processor because otherwise, you risk damaging the processor when you apply force to the heatsink.
The design considerations for your thermal management product play an important role in its success. These considerations include calculating the amount of heat that needs to be removed, determining the type of cooling needed, selecting a thermal interface material, and selecting a heatsink. Following these steps will help you create a product that is both efficient and reliable.