This part is a kind of semiconductor called 17N40K-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 17N40K-MT Preliminary 17A, 400V N-CHANNEL POWER MOSFET  DESCRIPTION The UTC 17N40K-MT is an N-channel mode power MOSFET using UTC’s advanced technology to provide customers with planar stripe and DMOS technology. This technology allows a minimum on-state resistance and superior switching performance. It also can withstand high energy pulse in the avalanche and commutation mode. The UTC 17N40K-MT is generally applied in high efficiency switch mode power supplies.  FEATURES * RDS(ON) < 0.24Ω @ VGS = 10 V, ID = 7.5 A * Low Gate Charge (Typical 47nC) * Low CRSS (Typical 11pF) * High Switching Speed  SYMBOL 2.Drain Power MOSFET 1.Gate 3.Source  ORDERING INFORMATION Ordering Number Lead Free Halogen Free 17N40KL-TF2-T 17N40KG-TF2-T Not [ ... ]

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