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Ref: Can you load Gerber files back into a PCB layout designer such as Eagle?

. . . . along with a dozen or so similar articles all over the web.

I strongly suspect the answer will be "No", but there's no harm in trying.

A company I have worked with in the past has a product - still in manufacture - that the design data and documentation were lost during a merger. They now wish to recreate the lost engineering data for their product and they have asked me to help.

I do not know exactly what existing data is available as of yet, (they're looking), but I strongly suspect that Gerber, silkscreen, BOM, and other data may be available as that is needed to actually manufacture the parts.

Aside from tracing the entire blasted thing by hand, is there any way to use the silkscreen and BOM files to help regenerate the schematic from the existing data? It seems like it should be doable since the Gerber gives you the wiring, the silkscreen gives you the component placement and the BOM tells you want the component is.

Aside from the data mentioned above, are there any other files or data objects I should ask them to look for?

The schematic can be a simple drawing instead of an Eagle or Fritzing file.

Any ideas?

Thanks!

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    \$\begingroup\$ There may be netlist information available along with the gerbers. For example ODB++ or some proprietary netlist. But even with that it will be a fairly manual process. \$\endgroup\$
    – user57037
    Jul 20, 2021 at 17:46
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    \$\begingroup\$ Sounds like a very expensive lesson your company is learning. Are the original engineers still alive? \$\endgroup\$ Jul 20, 2021 at 18:34
  • \$\begingroup\$ You'll be tracing quite a bit by hand. Any software for microcontrollers or anything is completely lost though. \$\endgroup\$
    – Hearth
    Jul 20, 2021 at 18:51
  • \$\begingroup\$ The trick is to print it out on a big piece of paper, grab some multi-colored pencils and your favorite schematic capture program, and have at it. There's no short cut and you're not allowed to make ANY mistakes. But unless it's a crazy-complex item, this isn't as bad as it sounds. You just have to be methodical and tick off every trace as you go. Good luck! \$\endgroup\$
    – Kyle B
    Jul 20, 2021 at 21:41

3 Answers 3

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the design data and documentation were lost during a merger. They now wish to recreate the lost engineering data for their product and they have asked me to help.

No, this cannot be done without some degree of engineering judgement from somebody. Design files that were originally generated within a reasonable quality system that will not be directly 100% recoverable are: -

  • Schematics (based on BoM below is somewhat feasible)
  • BoM (if you have proper netlist information)
  • Prototype testing information - impossible
  • Verification results - impossible
  • Validation results - impossible
  • Technical files and calculations - impossible
  • Product testing and calibration - impossible
  • Software (if any) - impossible

There's more to a design than just a schematic, BoM and gerber files if the product is designed within a recognizable QA system. Without all the files listed above, you may be subject to legal problems especially if the product is (say) CE marked.

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  • \$\begingroup\$ Software exists and can be used to annotate the schematic. Verification, validation, and other test documents may not be important. (And if they are, that's the moose's problem. I can't do everything.) If I can generate a usable schematic, I'll be jumping up and down! \$\endgroup\$ Jul 21, 2021 at 23:06
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What you are talking about is refered to as PCB reverse engineering and generally it takes an actual engineer to do it. That is not something that can be completely automated, the best automation you can hope for is grinding bare PCBs and recreating the layers from some good photos of the stuff but you already have all that as gerber files. Everything else is mostly a manual job, even just deciding where actual parts go and recreating a netlist can only be semi-autoamtic at best. It is a complicated task and in order to recreate all the lost documentation you need someone who knows what is going on on your board and who will use his time to just draw and write it all again. So if you have at least a slightest chance of recovering at least some of your lost files, dat recovery, some old backups, some copies on other developer PCs, etc., then I would definitely try to take it first.

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It will require a lot of work, basically reverse engineering, the same as an outsider would have to do.

If they can find a printed schematic of any description it can save a lot of work and avoid possible errors.

"The schematic can be a simple drawing instead of an Eagle or Fritzing file". This raises the question of "why" one would do this. To generate an updated PCB, other than very minor modifications one could consider doing at the Gerber level, you need the whole EDA chain working from schematic to PCB, and without errors. A schematic scrawled on the back of a napkin is not going to help with that. It might help with troubleshooting during construction. Even a rough block diagram with details on some particular possible trouble spots could suffice for that.

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