RFM3N50 Datasheet PDF - Intersil

These are N-Channel enhancement mode silicon gate power field effect transistors designed for applications such as switching regulators, switching converters, motor drivers, relay drivers, and drivers for high power bipolar switching transistors requiring high speed and low gate drive power. These types can be operated directly from integrated circuits.
Formerly developmental type TA17405.

FEATUREs
• 3A, 450V and 500V
• rDS(ON) = 3Ω
• Related Literature
    - TB334 “Guidelines for Soldering Surface Mount Components to PC Boards”