This part is a kind of semiconductor called 2SK3479.

Function of this product has MOS Field Effect Transistor.

Manufacturers : Kexin

Image and pinout :

Some of the text within the PDF file :

SMD Type MOS Field Effect Transistor 2SK3479 TO-263 +0.1 1.27-0.1 MOSFET Unit: mm +0.1 1.27-0.1 +0.2 4.57-0.2 Features Super low on-state resistance: RDS(on)1 = 11 m RDS(on)2 = 13 m MAX. (VGS = 10 V, ID = 42 A) +0.2 8.7-0.2 MAX. (VGS = 4.5 V, ID = 42 A) Low Ciss: Ciss = 11000 pF TYP. Built-in gate protection diode +0.1 1.27-0.1 0.1max +0.1 0.81-0.1 +0.2 5.28-0.2 2.54 5.08 +0.1 -0.1 +0.2 2.54-0.2 +0.2 15.25-0.2 +0.2 2.54-0.2 +0.2 0.4-0.2 Absolute Maximum Ratings Ta = 25 Parameter Drain to source voltage Gate to source voltage Drain current Power dissipation TC=25 TA=25 Channel temperature Storage temperature * PW 10 s,Duty Cycle 1% Tch Tstg Symbol VDSS VGSS ID Idp * PD Rating 100 20 83 332 125 1.5 150 -55 to +150 Unit V V A A W Electrical Characteristics Ta = 25 Parameter Dr [ ... ]

2SK3479 PDF Datasheet Download