This part is a kind of semiconductor called 2SK805.
Function of this product has N-Channel MOSFET Transistor.
Manufacturers : Inchange Semiconductor
Image and pinout :

Some of the text within the PDF file :
INCHANGE Semiconductor isc N-Channel MOSFET Transistor isc Product Specification 2SK805 DESCRIPTION ·Drain Current –ID=20A@ TC=25℃ ·Drain Source Voltage- : VDSS=200V(Min) ·Fast Switching Speed APPLICATIONS ·high speed power switching applications such as switching regulators, converters, solenoid and relay drivers. ABSOLUTE MAXIMUM RATINGS(Ta=25℃) SYMBOL ARAMETER VALUE UNIT VDSS VGS ID Ptot Tj Tstg Drain-Source Voltage (VGS=0) 200 V Gate-Source Voltage ±20 V Drain Current-continuous@ TC=25℃ 20 A Total Dissipation@TC=25℃ 100 W Max. Operating Junction Temperature 150 ℃ Storage Temperature Range -55~150 ℃ THERMAL CHARACTERISTICS SYMBOL PARAMETER MAX UNIT Rth j-c Rth j-a Thermal Resistance,Junction to Case 1.0 Thermal Resistance,Junction to Ambient [ ... ]
2SK805 PDF Datasheet Download
