Thermal resistance of electric device
As the equipment becomes more powerful and compact, engineers in different industries have been making unremitting efforts in the thermal management of electronic products. Although there are many creative solutions that can take away heat energy through high-temperature heat conduction devices such as fans, liquid coolers and heat conduction tubes, the device itself has also made a lot of progress to fundamentally optimize the thermal performance.
Working Temperature：
When designing end products such as IOT equipment, medical tools or industrial sensor devices, almost every device takes the maximum ambient operating temperature as a parameter. The maximum ambient temperature is set by the manufacturer of the device to ensure that the performance of the equipment reaches an acceptable standard and the physical characteristics are not damaged. For example, some switching transistors can withstand very high power loads, but their internal semiconductor junctions will melt if exposed to too high ambient temperature. In addition, the temperature will directly affect the conductivity of the material. If the maximum operating temperature is exceeded, the performance of the device may be changed.
Remove the heat from the source:
Devices with fixed internal power consumption and ambient temperature thresholds, like most power conversion devices and ICs, the surface temperature of the housing depends on the internal thermal resistance and the efficiency of heat transfer. Internal thermal resistance describes the efficiency of heat transfer from heat source to device surface. However, when most people think of heat management, they will think of the efficiency of heat transfer from devices to the environment, convective, conductive or radiant heat transfer. These methods are usually passive heat exchangers, fans, liquid cooling systems, heat pipes and heatsinks.
The best way to maintain a good shell temperature is to directly change the internal thermal resistance of the equipment and the efficiency of heat dissipation to the surrounding environment. A perfect thermal management device has zero thermal resistance and infinite heat dissipation. However, because devices are made of real-world materials, each material has its own unique thermal resistance characteristics, and no system can transfer heat perfectly, system designers must try to optimize the thermal performance of each key device from the early stage of design.
Fixed variable:
As we know, the various parameters of the application are usually fixed, so the design needs to be developed to meet these requirements. In some cases, the efficiency of the device, the ambient temperature and the heat transfer mechanism of the system depend on the final application. In many cases, if the device is to achieve acceptable operating conditions and low housing temperature, the only way is to improve the internal thermal design and select the device with low internal thermal resistance.
