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 TA17434.

FEATUREs
• 12A, 350V and 400V
• rDS(ON) = 0.380Ω
• Related Literature
    - TB334 “Guidelines for Soldering Surface Mount Components to PC Boards”