800 V N-channel in a fully isolated TO-220FP
The STF4N80K5 is an 800 V, 3 A N-channel MOSFET from ST's SuperMESH5 series, housed in a TO-220FP full-pack plastic package.
What the 2.5 Ohm Rds(on) and 10.5 nC Qg mean for your BOM
The 10.5 nC total gate charge is light: a small SOT-23 gate-drive IC or a simple RCD driver from the auxiliary winding can switch it at 65–100 kHz without excessive drive loss.
Active production — no last-time-buy clock ticking
ROHS3 compliance is confirmed, which keeps it eligible for EU and RoHS-restricted markets without an exemption review.
Package and mounting — the isolated tab advantage
The TO-220FP (supplier device package TO-220FP) is a fully moulded through-hole package with the backside tab encapsulated in epoxy. No mica washer or silicone pad is required between the tab and the heatsink — the isolation is built in. The through-hole leads suit point-to-point wiring on perf-board or a standard PCB layout with 0.100-inch pitch holes. Operating junction temperature range is -55 to 150 °C, covering industrial and many automotive under-hood environments.