PCB info embedded on a Gerber layer or in Word/PDF document?

[VK3DRB]

I don't think embedding general information text in a layer is a great idea, other than locking the info in with the Gerber. I think a README checklist as a Word document or PDF zipped up with the Gerbers and drill files is a better idea overall when you weight up the pros and cons. I have used both formats over the years, and PCB fabricators have never had problems with a README PDF added into the package.... I have always got what I needed with few, if any, questions asked. Of course it makes sense to point out instructions for specific regions of the PCB using embedded text in a Gerber layer.

Reasons:

1. From inheriting other designs, all too often I find text in the layer is not amended when there is a change, so it conflicts with PCB info. Eg: Mask says red in the embedded text, but the user selected green when buying the boards. A common mistake too is versions and dates. Miss changing a review date in the embedded info and then you may have re-spin the whole Gerber package if you have already released it, which will make you look silly.

2. Lack of ease of amending the embedded text. If you want to change the mask from red to green, you have to release a new Gerber package, which is time consuming and often a pain in the arse. Editing a README Word doc is much easier. It can be version controlled with the version controlled zipped file name.

3. Anyone can read a README Word or PDF document. Not everyone has the tools to read a embedded layer on a Gerber. All computer literate people can read a Word and PDF. But not everyone in you company (eg: Purchasing Department) can read embedded information other than what is printed out or exported to a hard-to-read PDF.

4. Sometimes, reading embedded text is painful on the eyes and always slower and more painful to edit compared to using a Word document.

5. The auto generated layer stack-up diagram can be easily exported to the Word document.

6. A Word document is portable and proforma. Not so with embedded text from one design to another, without a few hoops and hurdles.

7. The Gerber layer with the info (often called a drill drawing .gd1) is a separate file anyway, so there is no difference between a separate .doc, .pdf or .gd1

Any opinions on this from you on this, would be welcome!

[Batang]

Kinda miss Protel 99SE where you could embed all type of docs etc into its DB files.

I know, Not really relevant to the OP post but a nostalgic thought.

Cheers

[Pseudobyte]

I have always subscribed to the method of having separate revision status between fabrication drawings and physical PWB revisions. Granted these are usually in lock-step with each other, but in the instances when you need to change something like soldermask or silkscreen it is much easier to just modify the drawing.

[julianhigginson]

Absolutely, you should keep PCB fab doc separate to Gerber files. (I mean, keep the fab doc WITH the gerber files, but don't have the fab info in the gerber files)

Gerber files with fab notes embedded in them are terrible.

I use  draftsman for managing PCB FAB doc creation now. It's really easy to setup, and just works every time you change the design and need to regenerate fab docs.

Prior to this I used to use a separately maintained word doc, that I'd copy into a project and customise for each board release... It required a lot of cross checking and manual labour to do a release. It was a pretty big undertaking and unfortunately not so simple to always have right. When draftsman appeared, it was a revelation.

[SerieZ]

I have always kept a README file where I try to clarify all specifics down to any Layers as specific as possible.
When ordering from Würth I even put it in German AND English for whatever reason. 

Regarding point 3 I use a .txt file for a similar reason... maybe the person or computer receiving my files do not know what a .pdf is!!!

It sounds stupid, but I feel that including it in a Gerber file it could be overlooked... maybe I am just pedantic.

[Pseudobyte]

I generate a PDF of the fabrication drawing as well as the Gerber. From a quality perspective (quality system that is) it is easier to change revision on a drawing rather than the physical design.

[Kleinstein]

I would even prefer plain ASCII text over a Word document - word documents can have trouble with different program versions and possibly spread viruses and similar.  Word can still open a .txt file.

It is not guaranteed anyone who can read it will ever look at the text layers of the Gerbers. An additional layer is more like adding confusion and a chance it gets printed to the PCB in one way or the other.

[Pseudobyte]

I feel like that is super dependent on where you are having your PCBs fabricated. If i was sending data to OSHpark or pcbway I would definitely not send them a fabrication drawing. We require our suppliers to send us a checkplot and stackup of what they are going to build for approval. The industry I am involved with has very high standards for vendors and if a vendor did not read a fabrication drawing you can bet money that they would be seeing a vendor corrective action request show up in their inbox.

[VK3DRB]

Thanks. You replies confirms my suspicions that embedding the info into a Gerber is simply bad practice. I know a few companies that practice this this malarkey.

Speaking of bad practice or simple laziness,  on a PCB I inherited recently to make some big changes to, some previous engineer had "hard coded" signal names into pin names for a generic connector component symbol, THEN on reuse in another application, these irrelevant signal names were visible in the schematic as well as the totally different net names for the net application. Hence in the schematic for the connector, each pin in the connector had TWO signal names .