Component-style code 3LN02N is all the name of this 28.0 KB PDF provides; it is catalogued as a schematic but mentions no device, brand or motherboard number. A file of this size is typically a compact part sheet listing pin functions, voltage and current limits and the package outline. Repair technicians consult it to confirm a small part found near a rail, to orient probes correctly and to pick an equivalent. Since related codes differ only by suffix, check that the N variant matches the marking on the part.
The button opens the matching file on RM Schematics, or a source page if it is not catalogued there yet. The original attachment is from @cyberlanelectonik. Enginerys does not host this file.
How to open a .pdf file
The standard format for schematics, block diagrams, power-sequence charts and service manuals.