This part is a kind of semiconductor called K3994.
Function of this product has 2SK3994.
Manufacturers : Toshiba Semiconductor
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2SK3994 TOSHIBA Field-Effect Transistor Silicon N-Channel MOS Type (π−MOS V) 2SK3994 Switching Regulator, DC/DC Converter Applications Motor Drive Applications z Low drain−source ON-resistance z High forward transfer admittance z Low leakage current z Enhancement mode : RDS (ON) = 90 mΩ (typ.) : |Yfs| = 10 S (typ.) Unit: mm : IDSS = 100 μA (max) (VDS = 250 V) : Vth = 3.0 to 5.0 V (VDS = 10 V, ID = 1 mA) Absolute Maximum Ratings (Ta = 25°C) Characteristics Drain−source voltage Drain−gate voltage (RGS = 20 kΩ) Gate−source voltage Drain current DC (Note 1) Symbol VDSS VDGR VGSS ID IDP PD EAS IAR EAR Tch Tstg Rating 250 250 ±30 20 80 45 487 20 4.5 150 −55~150 Unit V V V A A W mJ A mJ °C °C Pulse (Note 1) Drain power dissipation (Tc = 25°C) Sin [ ... ]