This part is a kind of semiconductor called 12N50.

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 12N50 ·FEATURES ·Drain Current ID= 12A@ TC=25℃ ·Drain Source Voltage- : VDSS= 500V(Min) ·Static Drain-Source On-Resistance : RDS(on) = 0.5Ω(Max) ·Fast Switching ·APPLICATIONS ·Switch mode power supply. ·ABSOLUTE MAXIMUM RATINGS(Ta=25℃) SYMBOL PARAMETER VALUE UNIT VDSS VGS Drain-Source Voltage Gate-Source Voltage-Continuous 500 ±30 V V ID Drain Current-Continuous 12 A IDM Drain Current-Single Plused 48 A PD Total Dissipation @TC=25℃ 150 W Tj Max. Operating Junction Temperature 150 ℃ Tstg Storage Temperature -55~150 ℃ ·THERMAL CHARACTERISTICS SYMBOL PARAMETER MAX UNIT Rth j-c Rth j-a Thermal Resistance, Junction to Case Thermal Resistance, Junction to Ambient 0.65 [ ... ]

12N50 PDF Datasheet Download