This part is a kind of semiconductor called W18NK80Z.

Function of this product has STW18NK80Z.

Manufacturers : STMicroelectronics

Image and pinout :

Some of the text within the PDF file :

STW18NK80Z N-channel 800V - 0.34Ω - 19A - TO-247 Zener-protected SuperMESH™ Power MOSFET General features Type STW18NK80Z ■ ■ ■ ■ ■ VDSS 800V RDS(on) <0.38Ω ID 19A pW 350W Extremely high dv/dt capability 100% avalanche tested Gate charge minimized Very low intrinsic capacitances Very good manufacturing repeatibility TO-247 Description The SuperMESH™ series is obtained through an extreme optimization of ST’s well established strip-based PowerMESH™ layout. In addition to pushing on-resistance significantly down, special care is taken to ensure a very good dv/dt capability for the most demanding applications. Such series complements ST full range of high voltage MOSFETs including revolutionary MDmesh™ products. Internal schematic diagram Ap [ ... ]

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