In this tutorial, we are going to learn about use of Heat –Sink.
Below are main points which are use for Heat – Sink:
- All of our electrical devices are built by combining different electronics components together. Each component has a specific function. Let’s take an example of lighting circuit. The battery provides electrical energy the led produces light from the energy supplied by the battery and the resistance protect the led by reducing the current in the circuit. If we remove the resistor the led burn out. The reason why the led burn out because the resistor of the circuit is reduced.
- All components have a thermal limit or a max operating temperature. When exceed this certain temperature they will breakdown and potentially destroy the circuit board.
- Some components like fuse this is desirable because the material breaks. This instantly cuts the power to the circuit and helps to save the components damage but it also completely stops the circuit boards from working until the fuse is replaced with components like an IGBT.
- The buildup of heat isn’t good thing because as the increase in temperature they become unreliable and the current passing through them increase .This additional current creates heat which in turn allows more current to flow and so the components reaches a thermal runway and will eventually just destroy itself, so to increase the life of the component and the circuits board as well as to keep the components operating in a stable and reliable condition, we need a way to remove the thermal energy which the component generates.
- So how do we remove the thermal energy of the electronic components.Some components don’t need additional cooling. But in case when heat starts to increase in larger circuits we can use a simple fan to blow air across the components. The moving air will pick up and carry the heat away. This method is used in PC’s, that’s why fan are installed on it.
- We usually need a more effective way to get the heat out of the actual component and popular method is to use heat sink to provide passive cooling. This heat sink is usually made from aluminum. These heat sinks have multiple fins on them. The fins help to increase the surface area of the components to allow maximum exposure to more ambient air.
- The heat sink is made from a metal because this conducts heat well much better than air. So by making it for more heat to escape and increasing the exposure to the air we effectively cool down the components.
- There is a limit to how much we can remove with this method though and so the next stage is to use a fan to blow ambient air over the component and heat sink that’s exactly the method used in this DC bench power supply.