This part is a kind of semiconductor called 2SK4112.

Function of this product has Field Effect Transistor.

Manufacturers : Toshiba

Image and pinout :

Some of the text within the PDF file :

2SK4112 TOSHIBA Field Effect Transistor Silicon N Channel MOS Type (π-MOSVI) 2SK4112 Switching Regulator Applications • Low drain-source ON resistance: RDS (ON) = 0.75 (typ.) • High forward transfer admittance: |Yfs| = 5.5S (typ.) • Low leakage current: IDSS = 100 A (VDS = 600 V) • Enhancement mode: Vth = 2.0~4.0 V (VDS = 10 V, ID = 1 mA) Unit: mm Absolute Maximum Ratings (Ta = 25°C) Characteristics Symbol Rating Unit Drain-source voltage Drain-gate voltage (RGS = 20 kΩ) Gate-source voltage Drain current DC (Note 1) Pulse (t = 1 ms) (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 VDSS VDGR VGSS ID IDP PD EAS IAR EAR Tch Tstg [ ... ]

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