FET temperature rise

Current multiplied by Rds,on multiplied by thermal impedance. Don't forget to use an Rds,on appropriate to your temperature.

\(T_j = I^2 * R_{ds} * Z_{th} + T_a\)

Instructions: Select the variable you want to solve for, and fill in the others.

Solve Symbol Input Value Unit Description
\(I\)
\(A\) Current
\(R_{ds}\)
\(\Omega\) MOSFET R_ds,on
\(T_{j}\)
\(C\) Temp Rise at Junction
\(T_{a}\)
\(C\) Ambient Temp
\(Z_{h*t}\)
\(C/W\) Thermal Impedance, from junction to your reference point

References