This part is a kind of semiconductor called 2SK2057.

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 2SK2057 DESCRIPTION ·Drain Current ID= 20A@ TC=25℃ ·Drain Source Voltage- : VDSS= 500V(Min) ·Fast Switching Speed APPLICATIONS ·Switching regulators ·General purpose power amplifier ABSOLUTE MAXIMUM RATINGS(Ta=25℃) SYMBOL ARAMETER VALUE UNIT VDSS Drain-Source Voltage (VGS=0) VGS Gate-Source Voltage ID Drain Current-continuous@ TC=25℃ 500 ±30 20 V V A ID(puls) Pulsed Drain Current 80 A Ptot Total Dissipation@TC=25℃ 150 W Tj Max. Operating Junction Temperature 150 ℃ Tstg Storage Temperature Range -55~150 ℃ ·THERMAL CHARACTERISTICS SYMBOL PARAMETER MAX UNIT Rth j-c Rth j-a Thermal Resistance, Junction to Case 0.833 ℃/W Thermal Resistance, Junction to Ambient 50 ℃/W [ ... ]

2SK2057 PDF Datasheet Download