The difference between the size of the electronic heat sink, any device has a loss in the work. Most of the loss into heat. Small power device loss is small, no heat dissipation required. However, the loss of high-power devices is large. If no cooling measures are taken, the core temperature can reach or exceed the allowable junction temperature, and the devices will be damaged.
Therefore must add the radiator, The most common is to install the power device on the radiator, to dissipate heat into the surrounding space. If necessary, add a cooling fan to enhance the cooling with wind. In some large equipment, its power devices also use flow cold water cooling plate, it has better heat dissipation effect. Heat dissipation calculation is to determine the appropriate heat dissipation measures and radiators through calculation under working conditions. The power device is mounted on the radiator. Its main direction of heat flow is from the core to the bottom of the device, through the radiator to heat the surrounding space.
Small electronic radiator (or heat sink) is made of aluminum alloy sheet by stamping process and surface treatment, and large electronic radiator is made of aluminum alloy extrusion profile, and then by mechanical processing and surface treatment. They come in a variety of shapes and sizes for different device installations and for different power consumption devices.
Radiators are generally standard parts, but also can provide profiles, according to the user, cut into a certain length and made of non-standard radiators. The surface of the radiators is treated with electrophoretic paint or anodize to improve the heat dissipation efficiency and insulation performance. It can be increased by 10-15% in natural cooling and 3% in ventilated cooling, and can withstand 500 or 800V in electrophoretic coating. Electronic radiator manufacturers give the thermal resistance values or relevant curves for different types of radiators and different thermal resistance values under different heat dissipation conditions.