This part is a kind of semiconductor called 2SK2543.

Function of this product has Silicon N Channel MOS Type Field Effect Transistor.

Manufacturers : Toshiba Semiconductor

Image and pinout :

Some of the text within the PDF file :

2SK2543 TOSHIBA Field Effect Transistor Silicon N Channel MOS Type (π−MOSV) 2SK2543 Switching Regulator Applications Unit: mm l Low drain−source ON resistance : RDS (ON) = 0.75 Ω (typ.) l High forward transfer admittance : |Yfs| = 7.0 S (typ.) l Low leakage current : IDSS = 100 µA (max) (VDS = 500 V) l Enhancement−mode : Vth = 2.0~4.0 V (VDS = 10 V, ID = 1 mA) Maximum Ratings (Ta = 25°C) Characteristics Drain−source voltage Drain−gate voltage (RGS = 20 kΩ) Gate−source voltage Drain current DC (Note 1) Pulse (Note 1) Drain power dissipation (Tc = 25°C) Single pulse avalanche energy (Note 2) Avalanche current Repetitive avalanche energy (Note 3) Channel temperature Storage temperature range Symbol VDSS VDGR VGSS ID IDP PD EAS IAR EAR Tch Tstg Thermal [ ... ]

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