I am running OrCAD and I would like to start off by saying that I never use one of their footprints without editing it.
If this is on a connector or a device with lots of pins, the odd pad may be every 10th pad to assist in test or the field with locating a pin. A good thing.
But the same results could be done with a tick in the silkscreen.
For your layout person to say it is too much trouble to edit the footprint...well that is an opinion. In my opinion, it only takes a small amount of time to do the edit (even adding a tick into the silkscreen) and then the footprint can be replaced globally within the board database. The time up front is always shorter than the time a board spends in production.
Barbara J. Burcham, CID
SR PCB Designer
Fairfield Industries
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-----Original Message-----
From: Steve Gregory [mailto:[log in to unmask]]
Sent: Friday, June 21, 2002 1:54 PM
To: [log in to unmask]
Subject: [TN] PCB lay-out problem...
Hi all,
We're having a board lay-out done outside, and as with new designs, I will get asked to look at the preliminary gerbers to see if I can see anything out of place that might need changing.
I looked the the gerbers that were given to me and the first think I noticed was that on some IC footprints, there was 1 rectangular pad, then 9 pads where the corners were rounded, then a rectangular pad, and on and on...
So I fed that back to our engineer here who is over this project, then he fed that back to the individual who is doing the lay-out. Our engineer here then came back to me and asked if that would be a problem, and I told him it could be, but why not make all the pads uniform? Go to: http://www.stevezeva.homestead.com and look at "OrCad" to see what I mean.
His reply was that the individual doing the layout told him he would have to go in and manually edit each one of the pads that were rectangular, and that it would be too much trouble. He said this is the way OrCad put the footprint down, and if it was such a problem, why would OrCad have this footprint in the library? Then he added that the IPC-SM-782 says that you can either use rectangular pads or optionally round the corners, so that tells him you can use either one or both, and it doesn't make any difference. So he told the layout person to leave things as they are.
I don't know anything at all about OrCad, but something tells me there's an operator problem here. I've never seen a footprint like this before, and no matter what I say, I can't convince our engineer here that the footprint needs to be fixed.
HELP!!! PLEASE!!!
Thanks,
-Steve Gregory-
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