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No - once the PCB file is translated into a Gerber file, all the information about component rotation, reference pin, etc. is lost. Gerber files are simply lines and pads; there is nothing in the Gerber file that identifies components or their position.
There is a possibility that an assembly facility can generate placement files using optical targeting of the board. A LOT of manual setup would be required, and the process would be expensive. If the board is large and complex, it would probably be very costly.
It is built into the EDA software as a menu item - generally under "reports". The exact location of the command/function depends on which EDA package you are running. In 0rcad, for example, it is under Auto>Create Reports>Select Custom Reports. In Pr0tel, it is under Reports>Pick and Place. In PC@D is is under File>Reports>Pick and Place Locations. etc, etc...
Look in the CAM350 help menu for "reverse engineering". It will give you the step-by-step process for converting your Gerber and NC drill files back into a PCB file. Once you have completed the process, you'll be able to generate a "Part and Centroid Placement" report which can then be used as a pick and place file with the addition of component designator, and angle/rotation information.
This process will require you to select and assemble individual lines and pads on the Gerber into components.
Be advised that a large board is going to require a fast PC with a lot of memory. The procedure is also goint to take a lot of your time and effort. If you have no other alternative, perhaps it is worth the investment.
Another alternative, once the reverse engineering is done, would be to export the reverse engineered board to your EDA/CAD program if it is one supported by CAM350. You could do the balance of cleanup and report generation from there.
Usually you don't have to add nothing to the footprint design; when you export the P&P data, the tools generate coordinates only from the cells origin.
But you do have to supply enough information in your PP files so that the assembly company can match the footprint to the component library on the placement machine so that it knows which vision codes to use when checking alignment
P&P file is text file generated by CAD tool as mentioned above. You do not need to add anything to it is generated by software. It contains location and rotation of componants with refdes and on which side they are Top or Bot.
Majnoon: the alignment problem still remain! Consider a big BGA of fine pitch QFP device, or even 0201 SMD pakages you may need more data to properly monut them. Also it seems you need to follow special rule in origin place selection in footprint design! Any coment?
Centre X, Centre Y, Theta, Cref, Footprint, Part number
The first 3 are obvious, the last ones are so the CEM can MATCH these parts to the component library used by the actuall PP machines to do the job. These machines use a 'vision' library to determine correction method (camera/laser...) and lighting method (fore/back/strobed).
Also if you use parts like TO252 and TO263 the place centre is NOT the real center it is offset as the component body to which the vacum nozzle wil;l attach to is offset also.
In this case you should consider the rotational angles of each part relative to the pocket of the feeder in the PP machine.
I guess you do not do any DFM on your PCB. Have you any idea how much more manufacturable PCB designs can be if some of these simple things are done?
Once more for P&P is generated by CAD tool YOU or anyone else need not to add anything to it. Your comment is revealing as how much experience you have in board layout, and that some thing for your thought .
And Johnson for alighnment HAS nothing to do with P&P file your P&P file is generated by CAD tool for fine pitch componants you add fiducials on the board usually four but you need minimum two on the board for alighnment.
Once more for P&P is generated by CAD tool YOU or anyone else need not to add anything to it. Your comment is revealing as how much experience you have in board layout, and that some thing for your thought .
And Johnson for alighnment HAS nothing to do with P&P file your P&P file is generated by CAD tool for fine pitch componants you add fiducials on the board usually four but you need minimum two on the board for alighnment.
Perhaps 22 years experience of both PCB design and manufacturing is not enough for me, I will take your recommendation and go back to school. :sm16:
In the short time until I can start school again next year, I will continue to charge the €1,200 tooling fee for customers who supply PP data to me which is not complete or cannot be direct imported to the PP machine offline software because the board designer is too lazy to provide enough information. This happens 2 -3 times a week. I have to manually make up a table or combine PP adn BOM informations together, then create a map file to import.
Co-ordinates/rotation/Cref are NOT enough. Good PP data starts with good library management, which accounts for theta values being correct when relative to the position in the tape pocket, or the theta value has to be MANUALLY edited one line at a time to fix this.
Unless footprint & manufacturer are known, and theta value is relative to the orientation of the part in the tape pocket, then the correct vision model cannot be selected for the PP machine which includes Z height and position in tape pocket or tray.
But for now I am happy to make a good living from people who supply bad or too little data.
In the short time until I can start school again next year, I will continue to charge the €1,200 tooling fee for customers who supply PP data to me which is not complete or cannot be direct imported to the PP machine offline software because the board designer is too lazy to provide enough information. This happens 2 -3 times a week. I have to manually make up a table or combine PP adn BOM informations together, then create a map file to import.
Co-ordinates/rotation/Cref are NOT enough. Good PP data starts with good library management, which accounts for theta values being correct when relative to the position in the tape pocket, or the theta value has to be MANUALLY edited one line at a time to fix this.
Unless footprint & manufacturer are known, and theta value is relative to the orientation of the part in the tape pocket, then the correct vision model cannot be selected for the PP machine which includes Z height and position in tape pocket or tray.
But for now I am happy to make a good living from people who supply bad or too little data
I did not advise for you or any body to go back to school but come to think of it I agree with you school is good for every body.--))
I can see that you are talking from supplier point of view in this case Assembly House.
From designer side I also agree with you that a good library management is crucial to have error free or working design. This means origins for components be at the center of parts and for connectors at pin 1 and so forth. But to edit P&P file is not the job of PCB designer no matter how greedy or dishonest the assembly house could be to charge extra
for frivolous reasons.
A good designer ensures that the library he/she using is up to date
and all footprints are correctly made. Also they have correct marking indicating parts orientation on assembly drawing to make sure good and experience Assemblers can populate a board error free.
Some assembly houses require having Neutral file or Gencad file to be sent along with P&P file so they won’t have excuse to rip off their customers.
Of course pick and place info can be generated from Gerbers - all that is needed in Cam350 is to re-define your components (pin numbers for SM parts really don't matter), with a proper body outline - it will then generate a placement report with X/Y co-ordinates, I've done this many times. The software the assembly house uses for there machines can also do it, maybe even faster.
SiGiNT
George,
If you are using Pads just ascii out and import into Cam350 then generate the report from INFO-REPORTS-CENTROID menu.
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