The max power dissipation of my circuit is 20.5V x 0.5A = 10.25W, but transistors I found are 2W power dissipation. But my input voltages is just varied from 18.0V to 20.5V only. Do you think the 2W power dissipation transistor is fine? Any help will be appreciated.
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Power Electronics & Solar Energy
HeatSinks in Electronics - For all types of packages, there are heatsinks. They are mainly made of Black Anodized Aluminium. Aluminium is a good conductor of heat and Anodizing prevents any form of corrosion. Linear Regulated Supplies, RF Transmitters and Power Amplifiers have Devices that need heatsinks. Use Mica, Silpad, PolySulphone Pads for Electrical Isolation. HeatSink compound too.
Power Supplies Section
Design in such a way there is no short circuit or a a power resistor in source. But then efficiency drops. The best way is to use a switching supply design or keep the input voltage across transistor to a minimum.