Thermal Resistance & Heatsink Calculator

This tool models the thermal “circuit” from the silicon die (T_j) to the ambient air (T_a), determining if the component can dissipate heat safely on its own or if it requires a heatsink.

Use this tool to:

  • Predict Junction Temperature (T_j): Estimate how hot your component’s silicon will get under a specific power load.
  • Determine Heatsink Necessity: Quickly see if a standard package (like TO-220 or DPAK) requires a heatsink to stay below its maximum rated temperature (T_jmax).
  • Size a Heatsink: Calculate the maximum allowable thermal resistance (theta_sa) for a potential heatsink.
Input Parameters
Analysis Result
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