This part is a kind of semiconductor called MDF9N50F.

Function of this product has N-Channel Trench MOSFET.

Manufacturers : MagnaChip

Image and pinout :

Some of the text within the PDF file :

MDF9N50F N-channel MOSFET 500V MDF9N50F N-Channel MOSFET 500V, 8.0 A, 0.9Ω General Description The MDF9N50F uses advanced Magnachip’s MOSFET Technology, which provides low on-state resistance, high switching performance and excellent quality. MDF9N50F is suitable device for SMPS, HID and general purpose applications. Features  VDS = 500V  ID = 8.0A @VGS = 10V  RDS(ON) ≤ 0.9Ω @VGS = 10V Applications  Power Supply  HID  Lighting G DS Absolute Maximum Ratings (Ta = 25oC) Drain-Source Voltage Gate-Source Voltage Characteristics Continuous Drain Current Pulsed Drain Current(1) Power Dissipation Peak Diode Recovery dv/dt(3) Single Pulse Avalanche Energy(4) Junction and Storage Temperature Range ※ Id limited by maximum junction temperature TC=25oC TC=100oC TC= [ ... ]

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