STD19NF20 — 200V N-Channel MOSFET in DPAK, now obsolete
The 200 V drain-source rating gives headroom for 48 V bus, 72 V battery, or 120 V rectified mains in flyback or forward converters. Gate charge of 24 nC means a standard gate driver with 1 A peak can switch in tens of nanoseconds; the 800 pF input capacitance is modest, so drive losses are low even at 100 kHz.
