This part is a kind of semiconductor called 20N50.

Function of this product has FDP20N50.

Manufacturers : Fairchild Semiconductor

Image and pinout :

Some of the text within the PDF file :

FDP20N50 500V N-Channel MOSFET May 2006 FDP20N50 500V N-Channel MOSFET Features • 20A, 500V, RDS(on) = 0.23Ω @VGS = 10 V • Low gate charge ( typical 45.6 nC) • Low Crss ( typical 27 pF) • Fast switching • 100% avalanche tested • Improved dv/dt capability UniFET Description TM These N-Channel enhancement mode power field effect transistors are produced using Fairchild’s proprietary, planar stripe, DMOS technology. This advanced technology has been especially tailored to minimize on-state resistance, provide superior switching performance, and withstand high energy pulse in the avalanche and commutation mode. These devices are well suited for high efficient switched mode power supplies and active power factor correction. D G G DS TO-220 FDP Series [ ... ]

20N50 PDF Datasheet Download