820-3330 – Apple J31

The Apple J31, Apple 051-9585 and Apple A1286 are built on the 820-3330 board. ChambersDesignInc.com has indexed 10 files for this board — 3 BIOS files, 4 schematics and 3 boardviews.

Revisions seen in file names: B and 3.0. The BIOS dumps are 8 MB images. The earliest file dates from January 2021 (Cyberlan Electronics, Schematics & Boardviews Archive and BIOS Archive).

BIOS dumps 3

FileSizeRevAddedSource
3.9 MB
—
Get on Telegram BIOS Archive
4.2 MB
B
Get on Telegram BIOS Archive
4.2 MB
B
Get on Telegram BIOS Archive

Schematics 4

FileSizeRevAddedSource
820-3330B J31 PDF
Schematic.pdf
3.4 MB
—
Get on Telegram Schematics & Boardviews Archive +1 more
2.0 MB
3.0
Get on Telegram Schematics & Boardviews Archive +1 more
820-3330-B
Schematic
3.6 MB
B
Get on Telegram Schematics & Boardviews Archive +1 more
2.1 MB
B
Get on Telegram Schematics & Boardviews Archive +1 more

Boardviews 3

FileSizeRevAddedSource
J31 820-3330-B BDV
Boardview.bdv
200 KB
B
Get on Telegram Schematics & Boardviews Archive +1 more
820-3330-B BDV
Boardview.bdv
200 KB
B
Get on Telegram Schematics & Boardviews Archive +1 more
235 KB
B
Get on Telegram Schematics & Boardviews Archive +1 more

Board facts

Board number820-3330
NumberingApple board number
RevisionsB, 3.0
BIOS chip size8 MB
First seen2021-01-25
Source channelsCyberlan Electronics, Schematics & Boardviews Archive, BIOS Archive
About the numberApple logic boards are numbered 820-xxxx or 820-xxxxx; the trailing letter is the revision.

Apple models for this logic board

A-numberModelYears
A1286MacBook Pro 15-inch2008–2012

A-numbers come from the file names; the model names and years are Apple's published identifiers.

Laptops that use 820-3330

What these files are for

A BIOS dump is a full image of the board's SPI flash chip. It is written back with an SPI programmer when the original firmware is corrupted, after a chip replacement, or to recover from a failed update. Read and save the original chip first: serial number, DMI data and the Intel ME / AMD PSP state differ between boards.

A schematic is the circuit diagram of the main board: power rails, power-up sequence, component values and net names. It is the reference for measuring voltages and tracing a fault.

A boardview is the component placement map of the PCB: click a part or a net and the viewer highlights where it is and what it connects to. Used together with the schematic to find test points.

Tools to open these files

FormatWhat it isOpen with
.bdvHonhan .bdv boardviewOpenBoardView, FlexBV or Honhan BoardViewer
.binraw SPI flash imagea CH341A, XGecu T48 / TL866II Plus or RT809H programmer
.pdfPDF schematicany PDF reader; Sumatra PDF and Foxit handle large schematics well
.rarRAR archive7-Zip or WinRAR
.zipZIP archive7-Zip, WinRAR or the built-in Windows extractor

Questions

What BIOS chip size does 820-3330 use?

The BIOS images for 820-3330 are 8 MB.

Is there a boardview for 820-3330?

Yes, 3 boardview files in .bdv format.

Which laptops use the 820-3330 board?

Files in the catalog link 820-3330 to the Apple J31, Apple 051-9585 and Apple A1286.

Where do the download links go?

Each button opens the original public Telegram post the file was shared in. ChambersDesignInc.com only indexes and cross-references those posts.