This part is a kind of semiconductor called 11N50K-MT.

Function of this product has N-CHANNEL POWER MOSFET.

Manufacturers : Unisonic Technologies

Image and pinout :

Some of the text within the PDF file :

UNISONIC TECHNOLOGIES CO., LTD 11N50K-MT Preliminary 11A, 500V N-CHANNEL POWER MOSFET  DESCRIPTION The UTC 11N50K-MT is an N-channel enhancement mode power MOSFET. It uses UTC advanced planar stripe, DMOS technology to provide customers perfect switching performance, minimal on-state resistance. It also can withstand high energy pulse in the avalanche and commutation mode. The UTC 11N50K-MT is universally applied in electronic lamp ballasts based on half bridge topology, high efficiency switched mode power supplies, active power factor correction, etc.  FEATURES * RDS(ON) < 0.55Ω @ VGS = 10 V, ID = 5.5 A * Fast Switching * With 100% Avalanche Tested  SYMBOL 2.Drain Power MOSFET 1.Gate 3.Source  ORDERING INFORMATION Ordering Number Lead Free Halogen Free 11N50KL-TF [ ... ]

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