Reference for the Atmel AT45DB041B, a 4-megabit serial DataFlash memory as the name states, in a 233 KB PDF. Expect the datasheet with pinout, page and buffer architecture, SPI command set and timing. Technicians use it when reading or programming the chip with a programmer, since its page size and commands differ from standard 25-series SPI flash and not every tool supports it. Always back up the original contents and confirm the exact part marking before writing.
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.