650 V, 45 mOhm — the numbers that decide the BOM
The STP65N045M9: It is built on MDmesh M9 technology, a planar structure that keeps the on-resistance low while handling 650 V drain-source. This combination targets high-voltage switching applications — power-factor-correction stages, flyback and LLC resonant converters, and motor drives where the DC bus sits at 400 V or below.
The 650 V Vdss provides margin above a typical 400 V PFC rail. Gate charge of 80 nC at 10 V is moderate. The 4610 pF input capacitance at 400 V Vds sets the miller plateau width.
Through-hole TO-220-3. The tab is the drain. No AEC-Q grade is stated, so treat it as an industrial-grade device unless you verify otherwise.