950 V N-channel in a fully insulated TO-220FP
The STF20N95K5 is an N-channel MOSFET from ST's SuperMESH5™ series, rated for a drain-source voltage of 950 V and a continuous drain current of 17.5 A at 25°C case temperature.
That on-resistance, multiplied by the square of the RMS drain current, is the conduction loss you need to shed through the TO-220FP package. For a 100 kHz hard-switched converter, the gate-drive power is roughly 40 nC × 10 V × 100 kHz = 40 mW, well within a standard driver's capability.
Thermal and rework perspective on the TO-220FP
The TO-220FP is a through-hole part with a fully moulded plastic body — no exposed metal tab. Maximum power dissipation is 40 W at case temperature. For rework, the through-hole leads are accessible from the solder side; the plastic body handles a standard soldering iron profile without issue.