Thermal Resistance Values Heatsink

For the thermal resistances i used the via thermal resistance calculator and approximated the thermal resistance with the vias to be around 4 4 c w using the values from the via calculation tool.

Thermal resistance values heatsink.

Thermal resistance is a heat property and a measurement of a temperature difference by which an object or material resists a heat flow thermal resistance is the reciprocal of thermal conductance. In other words the thermal resistance value ofa chosen heat sink for the application has to be equal to or less than r sa value for the junction temperature to be maintained at or below the specified t j. Model dimensions materials and properties. A thermal interface material or mastic aka tim is used to fill the gaps between thermal transfer surfaces such as between microprocessors and heatsinks in order to increase thermal transfer efficiency it has a higher thermal conductivity value in z direction than xy direction.

Due to recent technological developments and public interest the retail heat. With all the parameters on the right side of the r sa expression identified it becomes the required maximum thermal resistance of a heat sink for the application. Specific thermal resistance or thermal resistivity r. To estimate the pcb thermal resistance the board will be elevated off the table to prevent using the table a heatsink.

The curved data sets in figure 2 demonstrate the heat flux distribution through the tim2 material determined for the lowest and highest conductivity heat sinks at a value of heat sink width w hs 70 mm and over the full range of h eff they show that even for a package with a 1 mm thick lid made of pure copper the heat flux is. The following equation is used to calculate r hs the thermal resistance of the heat sink.