This part is a kind of semiconductor called B12NM50.

Function of this product has STB12NM50.

Manufacturers : STMicroelectronics

Image and pinout :

Some of the text within the PDF file :

STP12NM50 - STP12NM50FP STB12NM50 - STB12NM50-1 N-channel 550V @ tjmax - 0.30Ω - 12A TO-220/FP/D2/I2PAK MDmesh™ Power MOSFET General features Type STB12NM50 STB12NM50-1 STP12NM50 STP12NM50FP ■ ■ ■ ■ ■ VDSS (@Tjmax) 550V 550V 550V 550V RDS(on) <0.35Ω <0.35Ω <0.35Ω <0.35Ω ID 12A 12A 12A 12A 3 1 3 1 2 3 1 2 TO-220 TO-220FP High dv/dt and avalanche capabilities Low input capacitance and gate charge 100% avalanche tested Low gate input resistance Tight process control and high manufacturing yields D²PAK 3 12 I²PAK Internal schematic diagram Description The MDmesh™ is a new revolutionary MOSFET technology that associates the Multiple Drain process with the Company’s PowerMESH™ horizontal layout. The resulting product has an outstanding low on-resistance, [ ... ]

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