This part is a kind of semiconductor called K2381.

Function of this product has 2SK2381.

Manufacturers : Toshiba Semiconductor

Image and pinout :

Some of the text within the PDF file :

2SK2381 TOSHIBA Field Effect Transistor Silicon N Channel MOS Type (L −π−MOSV) 2 2SK2381 Chopper Regulator, DC−DC Converter and Motor Drive Applications z Low drain−source ON resistance z High forward transfer admittance z Low leakage current z Enhancement mode : RDS (ON) = 0.56 Ω (typ.) : |Yfs| = 4.5 S (typ.) Unit: mm : IDSS = 100 μA (max) (VDS = 200 V) : Vth = 1.5~3.5 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 200 200 ±20 5 20 25 65 5 2.5 150 −55~150 Unit V V V A A W mJ A mJ °C °C Pulse (Note 1) Drain power dissipation (Tc = 25°C) Single pulse [ ... ]

K2381 PDF Datasheet Download