This part is a kind of semiconductor called STP11NB40.

Function of this product has N-CHANNEL PowerMESH MOSFET.

Manufacturers : ST Microelectronics

Image and pinout :

Some of the text within the PDF file :

® STP11NB40 STP11NB40FP N - CHANNEL 400V - 0.48Ω - 10.7A - TO-220/TO-220FP PowerMESH™ MOSFET TYPE ST P11NB40 ST P11NB40FP s s s s s V DSS 400 V 400 V R DS(on) < 0.55 Ω < 0.55 Ω ID 10.7 A 6.0 A TYPICAL RDS(on) = 0.48 Ω EXTREMELY HIGH dV/dt CAPABILITY 100% AVALANCHE TESTED VERY LOW INTRINSIC CAPACITANCES GATE CHARGE MINIMIZED 3 1 2 3 1 2 DESCRIPTION Using the latest high voltage MESH OVERLAY™ process, STMicroelectronics has designed an advanced family of power MOSFETs with outstanding performances. The new patent pending strip layout coupled with the Company’s proprietary edge termination structure, gives the lowest RDS(on) per area, exceptional avalanche and dv/dt capabilities and unrivalled gate charge and switching characteristics. APPLICATIONS s [ ... ]

STP11NB40 PDF Datasheet Download