This part is a kind of semiconductor called FS5KM-5.

Function of this product has HIGH-SPEED SWITCHING USE.

Manufacturers : Mitsubishi Electric Semiconductor

Image and pinout :

Some of the text within the PDF file :

MITSUBISHI Nch POWER MOSFET FS5KM-5 HIGH-SPEED SWITCHING USE FS5KM-5 OUTLINE DRAWING 10 ± 0.3 6.5 ± 0.3 3 ± 0.3 Dimensions in mm 2.8 ± 0.2 15 ± 0.3 φ 3.2 ± 0.2 14 ± 0.5 3.6 ± 0.3 1.1 ± 0.2 1.1 ± 0.2 0.75 ± 0.15 0.75 ± 0.15 2.54 ± 0.25 2.54 ± 0.25 4.5 ± 0.2 q GATE w DRAIN e SOURCE 1 2 3 2.6 ± 0.2 w ¡VDSS .. 250V ¡rDS (ON) (MAX) .. 1.3Ω ¡ID .. 5A ¡Viso .. 2000V q e TO-220FN APPLICATION SMPS, DC-DC Converter, battery charger, power supply of printer, copier [ ... ]

FS5KM-5 PDF Datasheet Download