The STP25N80K5 is an 800 V, 19.5 A N-channel power MOSFET from STMicroelectronics' SuperMESH5™ series, built on a metal-oxide semiconductor process. It is a through-hole device in a TO-220-3 package, designed for high-voltage switching applications where the combination of 800 V drain-source breakdown and 19.5 A continuous current capability is needed. Typical deployment includes the primary-side switch in offline flyback converters, PFC boost stages, and two-switch forward topologies in industrial power supplies and lighting ballasts. The SuperMESH5™ platform brings a fast-recovery body diode and optimized gate charge profile, which reduces switching losses in hard-switched bridges.
260 mOhm on-resistance — conduction loss budget
At 10 A load, expect roughly 26 W dissipated in the die alone before switching losses. That number drives the heatsink selection — the 250 W package limit (Tc) is a theoretical ceiling; real designs derate heavily.
40 nC gate charge — driver compatibility
Gate charge of 40 nC at 10 V is moderate for an 800 V MOSFET in this current class.
Temperature range and package — mounting reality
The TO-220 package with through-hole mounting is straightforward for rework and prototyping. The exposed metal tab is the drain; thermal interface material and a screw or clip mount to the heatsink are standard practice.
It is a current-production part, not subject to last-time-buy or end-of-life notices as of the latest record.