Skip to main content
Log in
STMicroelectronics STF40NF20 — Discrete Semiconductors

STF40NF20 STripFET N-Channel MOSFET, 200 V, 40 A, TO-220FP

MPNSTF40NF20
Active

STMicroelectronics STripFET™ STF40NF20, N-Channel MOSFET, 200 V Vds, 40 A Id, 45 mOhm Rds(on) @ 20 A, 10 V, TO-220-3 Full Pack (TO-220FP), Through Hole, ±20 V Vgs(max).

$3.8000Ref. price · indicative, final on quote
STMicroelectronics STF40NF20 datasheet (PDF)
Independent supplier — new & surplus stockAuthenticity-screened · ESD-safe packingListing updated Aug 2026

Specifications

STF40NF20 specifications
ParameterValue
SeriesSTripFET™
FET typeN-Channel
MountingThrough Hole
Drain to source voltage200 V
Drive voltage (Max rds on, min rds on)10V
Current - continuous drain (Id) @ 25°C40A (Tc)
Power dissipation40W (Tc)
Operating temperature-55°C~150°C(TJ)
PackageTube
Vgs±20V
TechnologyMOSFET (Metal Oxide)
CaseTO-220-3 Full Pack
Vgs(th) (Max) @ id4V @ 250µA
Rds on (Max) @ id, vgs45mOhm @ 20A, 10V
Gate charge (Qg) (Max) @ vgs75 nC @ 10 V
Input capacitance (Ciss) (Max) @ vds2500 pF @ 25 V

Product details

200 V, 40 A N-channel switch in an isolated-tab TO-220

The STF40NF20 is a 200 V, 40 A N-channel power MOSFET from ST's STripFET trench-gate family, housed in the TO-220 Full Pack (TO-220FP) through-hole package. The full-pack moulding isolates the metal tab from the drain, so the device can be bolted directly to a heatsink or chassis without an insulating washer — a real time-saver on the assembly line and a BOM simplification for offline power supplies, motor drives, and DC-DC converters where the heatsink is grounded.

That number sets the conduction loss at full load: at 20 A the I²R dissipation hits about 18 W, which is manageable inside the 40 W package limit (Tc) if the heatsink is sized right.

No last-time-buy notice, no end-of-life risk.

Frequently asked questions

What is the Rds(on) of STF40NF20?

The maximum Rds(on) is 45 mOhm at a drain current of 20 A with a 10 V gate-to-source drive. This is the figure to use for conduction-loss calculations in the power stage.