This part is a kind of semiconductor called SMK630D.

Function of this product has Advanced N-Ch Power MOSFET.

Manufacturers : KODENSHI KOREA

Image and pinout :

Some of the text within the PDF file :

SMK630D Advanced N-Ch Power MOSFET DC-DC CONVERTER APPLICATION HIGH VOLTAGE SWITCHING APPLICATIONS Features     High Voltage : BVDSS=200V(Min.) Low Crss : Crss=24pF(Typ.) Low gate charge : Qg=12nC(Typ.) Low RDS(on) : RDS(on)=0.4Ω(Max.) D Ordering Information Type No. SMK630D Marking SMK630 Package Code TO-252 G S TO-252 Marking Diagram SMK 630 YWW Column 1,2 : Device Code Column 3 : Production Information e.g.) YWW -. YWW : Date Code (year, week) Absolute maximum ratings (TC=25C unless otherwise noted) Characteristic Drain-source voltage Gate-source voltage Drain current (DC) * Drain current (Pulsed) Power dissipation Avalanche current (Single) Single pulsed avalanche energy Avalanche current (Repetitive) Repetitive avalanche energy Junction temperature Storage te [ ... ]

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