This part is a kind of semiconductor called K4115.
Function of this product has 2SK4115.
Manufacturers : Toshiba Semiconductor
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2SK4115 TOSHIBA Field Effect Transistor Silicon N-Channel MOS Type (π- MOSⅣ) 2SK4115 Switching Regulator Applications • • • • Low drain-source ON resistance: RDS (ON) = 1.6 Ω (typ.) High forward transfer admittance: ⎪Yfs⎪ = 5.0 S (typ.) Low leakage current: IDSS = 100 μA (max) (VDS = 720 V) 3.3max. 2.0 9.0 20.0±0.3 2.0 Ф3.2±0.2 1.0 4.5 Unit: mm 15.9max. Enhancement model: Vth = 2.0~4.0 V (VDS = 10 V, ID = 1 mA) Characteristic Drain-source voltage Drain-gate voltage (RGS = 20 kΩ) Gate-source voltage Drain current DC Pulse (Note 1) (Note 1) Symbol VDSS VDGR VGSS ID IDP PD EAS IAR EAR Tch Tstg Rating 900 900 ±30 7 21 150 491 7 15 150 −55~150 Unit V 1.8max. 1.0 －0.25 ＋0.3 5.45±0.2 0.6－0.1 ＋0.3 5.45±0.2 4.8max. 1 2 3 2.8 V V A [ ... ]