The STF7NM80 is an 800 V, 6.5 A N-channel power MOSFET from ST's MDmesh series, packaged in a TO-220 Full Pack (TO-220FP). The full-pack moulding leaves no exposed metal tab — the back of the package is epoxy, so you mount it directly to a heatsink or chassis without an insulating pad or mica washer. That saves a BOM line and a manual assembly step per device. The 800 V drain-source rating puts this part squarely in the high-voltage primary-side switching space: offline flyback converters, PFC stages, auxiliary power supplies in industrial and telecom gear, and 2-switch forward topologies.
1.05 Ohm on-resistance — conduction loss budget
Rds(on) is specified at 1.05 Ohm maximum with 10 V gate drive at 3.25 A drain current. That is a moderate on-resistance for an 800 V device — expect conduction losses around 6.8 W at 3.25 A continuous, which the 25 W power dissipation rating can handle with adequate heatsinking. The gate charge is 18 nC at 10 V, so the gate-drive power requirement is modest; a standard MOSFET driver or a PWM controller output can drive it directly. For higher-frequency resonant or quasi-resonant designs, the switching loss contribution stays within the thermal budget.
Military temperature range and mounting
The TO-220FP through-hole package is a standard 3-pin layout — the gate threshold is 5 V maximum at 250 µA, so a 10 V gate drive ensures full enhancement with margin.
The part is ROHS3 compliant. For the procurement desk: this is a standard-shelf item through the franchised channel; no allocation or end-of-life urgency to factor into the BOM risk register.