Apple board 820-1955 labelled DC-DC, a 240 KB RAR archive that likely covers a power conversion daughterboard rather than the main logic board. No schematic number or revision is stated, so confirm the 820 code on the PCB before use. Documents for a DC-DC board help when there is no power, letting you check input voltage, regulator output rails, enable signals and the connector feeding the main board. Unpack it with WinRAR or 7-Zip and inspect the contents before measuring live circuits.
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 @Mac_Shematic_Santale. Enginerys does not host this file.
All sources (3)
The same file was posted more than once. If one link is dead, try the next.
| Channel | Posted | |
|---|---|---|
| @Mac_Shematic_Santale | 5 Jul 2019 | Open file on RM Schematics |
| @IT_SERVICE_WORLD | 28 Sept 2019 | Open file on RM Schematics |
| @IT_SERVICE_WORLD | 2 May 2021 | Open file on RM Schematics |
How to open a .rar file
Compressed archive — the usual wrapper for a schematic + boardview pair or a BIOS + EC set.