650 V N-channel in TO-220 — the switching MOSFET for offline supplies
The STP16N65M5: Packaged in a through-hole TO-220-3, it targets hard-switching topologies in AC-DC converters, power-factor-correction stages, and auxiliary power supplies where the 650 V margin covers universal mains input with derating for ringing on the drain node.
299 mOhm on-resistance — conduction loss budget
For a 12 A peak load, conduction loss at full current reaches about 43 W (I²R), which the 90 W power-dissipation rating at case temperature can handle provided the heatsink keeps Tc below 150°C. The 45 nC total gate charge at 10 V means the gate driver sees a moderate capacitive load — a typical 1 A driver can switch the FET in under 50 ns, keeping crossover losses manageable at 50–100 kHz.