Heat Sink Calculator

Calculate required heat sink thermal resistance.

Power Dissipation (W)

Max Junction Temp (C)

Ambient Temp (C)

Junction-to-Case Theta (C/W)

Formula

Theta HS = (Tj Max - Ambient) / Power - Theta JC - Theta CS

What is thermal resistance?

Thermal resistance measures how well heat flows, in degrees C per watt.

Lower thermal resistance is better?

Yes. Lower C/W means the heat sink dissipates heat more effectively.