Boardview for the Apple MacBook A1181 with logic board 820-2496, in BRD format. Apple 820- numbers identify the specific logic board design, and the same model number can come with several boards, so check the number on your PCB. BRD boardviews open in OpenBoardView, FlexBV and similar viewers, letting you locate components by reference, follow nets and find measurement points. Technicians use it alongside the schematic to chase power rail shorts, failed chargers and missing voltages.
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 @boardviews. Enginerys does not host this file.
How to open a .brd file
The most common boardview extension. Several unrelated formats share it, which is why one viewer opens a .brd and another refuses it.