PCB file query

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Hi,  Doing my fitst PCB in years and years, using an ancient DOS package.
Appreciate if someone could help me with the following:

Does a .PCB file extension suggest a standard format, or might it be package
specific?

Would one expect a board manufacturer to be able to handle an HPGL or
postscript plot file without undue difficulty?

How does one specify a drill file these days? I used to present it as a list
of X,Y coordinates, in inches. Is that approach still usable?

TIA



Re: PCB file query


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   That would be Autotrax or Easytrax? usually most manufactuers will
cope with that format or with a Gerber format file. I was under the
impression the drill size was incorporated with the .PCB file itself.

I've never used any manufactuers as i found it was easier to make them
myself as I didn't want solder masks and component overlays.

Regards
Mark

Re: PCB file query


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Hi Bruce,

Contact the PCB manufacturer of your choice & ask if they can read .PCB files
from Autotrax Version 1.2 (or what ever you happen to be running).
If they can't, ask how they want it presented. Some are more flexible than
others.
Most places extract all the info they need from just the .PCB file, so you need
to make sure all the pads have the correct hole sizes specified. Find out how
many different drill sizes their drill holds or you may be up for a surcharge if
they have to do 2 drilling passes. Watch oval & rectangular pads in old Protel
programs as they may not rotate correctly. Best to stick with circular pads.

You'll also need to ask how they want the outline of the board to be shown.
Showing it on Mechanical Layer 1 is a common way.
Make sure that the ends of the outline tracks join perfectly as it may cause the
router to fall over if they don't. Some manufacturers check for things like
that, others assume you have checked the board for all possible errors.


Cheers,
Ian Du Rieu

Re: PCB file query



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Bruce, further to Ian's comments, it is really a package-dependent and
fab-dependent answer.  Generally the fab's website will provide details of what
they accept.

Some (eg Futurlec, and most aus-based manufacturers) have no dramas with
EasyTrax/AutoTrax formats.  Those files have all the info required.  Piece or
proverbial.

Others (eg Olimex) weant Gerber RS274X format which is not available directly
from the output of the above programs.

Note that the board outline is often shown in the keep-out layer.  That's what I
normally do with AutoTrax, and have used BEC in Brissie, CustomPCB in Malaysia
and Futurlec in Thailand with them.  If you do use CustomPCB, beware octagonal
pads - their driver rotates them all 22.5 degrees for some bizarre reason.

Give me a ring if you want to discuss further.

Peter

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But they do take Eagle .BRD files directly. Just got my first batch
of boards from Olimex last Wed. A few dramas learning Eagle's quirks,
like using "net" instead of "wire" in schematics, similar in the
board layout. It's a pretty good package - much preferable over *Trax
because you enter your schematic first and it ensures that everything
is wired correctly on the board (electrical check), then a design
rules check to make sure that the manufacturer can *make* what you've
drawn. You get neither of those major benefits with *trax...

Re: PCB file query


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Yes you do, if you have the companion schematic program for AutoTrax,
which Protel are still being stubborn about releasing publically like
they did for AutoTrax.
In fact you CAN do a DRC in AutoTrax without the schematic package by
generating a netlist from the board and then running the DRC tool.
Allows you to check all the usual DRC stuff (track width/spacing etc)
except for your schematic matching of course.

Dave :)


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You actually do, as Dave pointed out.

And recall that the O/P has .PCB files, so he is already within the (presumably)
Protel product range.

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