This part is a kind of semiconductor called D5N50.

Function of this product has 5A N-Channel MOSFET.

Manufacturers : Alpha & Omega Semiconductors

Image and pinout :

Some of the text within the PDF file :

AOD5N50 500V,5A N-Channel MOSFET General Description Product Summary The AOD5N50 is fabricated using an advanced high voltage MOSFET process that is designed to deliver high levels of performance and robustness in popular AC-DC applications.By providing low RDS(on), Ciss and Crss along with guaranteed avalanche capability this device can be adopted quickly into new and existing offline power supply designs. VDS ID (at VGS=10V) RDS(ON) (at VGS=10V) 100% UIS Tested! 100% Rg Tested! 600V@150℃ 5A < 1.6Ω Top View TO252 DPAK Bottom View D D S G G S G Absolute Maximum Ratings TA=25°C unless otherwise noted Parameter Symbol Drain-Source Voltage VDS Gate-Source Voltage VGS Continuous Drain TC=25°C CurrentB TC=100°C Pulsed Drain Current C Avalanche Current C Repetitiv [ ... ]

D5N50 PDF Datasheet Download