500V, 11A, TO-220FP — switching power design anchor
The STF13NK50Z is an N-channel 500 V, 11 A MOSFET from ST's SuperMESH™ series, built on a planar stripe layout that balances on-resistance with rugged avalanche capability.
Thermal and switching budget
The 30 W power dissipation ceiling at the case (Tc) is a hard limit for heatsink sizing — in a 50°C ambient with a 60°C/W heatsink the usable dissipation drops to about 15 W before the junction hits 150°C. Input capacitance Ciss is 1600 pF at 25 V Vds, which together with the 47 nC gate charge sets the drive current requirement: a 1 A gate driver can switch the 47 nC gate in roughly 47 ns, though the practical turn-on/off time depends on the gate loop inductance and the driver's sink/source asymmetry.
Package and mounting — the full-pack advantage
The TO-220FP (TO-220 Full Pack) isolates the backside tab electrically — the die sits on a moulded resin body, not a metal tab. This means the screw-down tab can contact the heatsink directly without a silicone pad or mica washer, cutting assembly time and thermal resistance. The trade-off is slightly higher RthJC compared to a standard TO-220, so the 30 W dissipation limit is the relevant derating anchor.
For BOM planning, the base product number STF13 means the same die is offered in other packages (STP13NK50Z in TO-220, STW13NK50Z in TO-247) if the board layout or thermal budget changes later.