BIOS firmware for ThinkPad L390 laptops, machine type 20NS, from Lenovo. The name gives no board number or version, so the machine type is the main matching key, and it is printed on the bottom label. Images like this are written to the SPI flash with a programmer to recover from corruption or failed updates. Read the original chip first to keep serial and UUID data, and check that the extracted image is the same size as the flash chip.
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 @biosfilebins. Enginerys does not host this file.
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.
Back up your own chip before writing any dump, and match the full board number and revision. Flashing guide →