Electronics Forum | Fri Oct 20 07:03:46 EDT 2006 | sliebl
I really appreciate the input, guys. Having only had the opportunity to run the Contact machines, I was not aware that many of the other machines use coordinates for locals. Now about those damn, mid-chip solder balls.... oh, that's another topic.
Electronics Forum | Fri Oct 20 09:13:14 EDT 2006 | sliebl
nodlac, You are correct with the SMEMA3.1 document. Also, please note that I said I like to use local fids for
Electronics Forum | Fri Feb 19 09:20:01 EST 1999 | Stefan Witte
If the fiducials are rejected from the vision system, I would not relay on the accuracy of the position. Again, I would like to point out that the circle shape has a somewhat sinoid contrast in X- and Y- direction ( same as a diamond shape, but recta
Electronics Forum | Thu Oct 19 12:18:46 EDT 2006 | curious
Maybe I'm missing something here (we don't use locals and have never found them to be helpful, Panasonic and Fuji) but the fid coordinates don't necessarily have to be the same position in relation to the part placed. If you can use global fids. (whi
Electronics Forum | Fri Oct 20 04:07:15 EDT 2006 | Base
I know that on Philips Topaz equipment you can define the XY locations of the individual local fids relative to the mount-center of the component that they apply to. So if they are not symmetrical w.r.t. to the QFP's center there's no harm done. You
Electronics Forum | Fri Jun 10 18:44:28 EDT 2005 | Frank
This depends on how the software of your particular machine was written (designed) to handle local fids. Most machines do not have a requirement about the position of the local fids. The purpose of local fids are the same as global fids. All the p
Electronics Forum | Wed May 24 15:45:38 EDT 2000 | JAX
John, Would you enlighten us to what machines you are talking about. I have never heard of such things. Typically, machines map out the boards with the locations of the fiducials relative to there CAD locations in order to account for stretch. Local
Electronics Forum | Fri Jun 10 14:22:53 EDT 2005 | pr
Are the local fids. necessary? Anyway, I can't think of any reason the local fids. would have to be spaced exactly the same distance from the part. We place BGA's and QFP's using board fids, and have yet to find a problem that local fids helped fix.
Electronics Forum | Mon Mar 01 20:53:28 EST 2004 | Ken
How does a fiducial work? I am going to venture a guess as how it ralates to the parts you are trying to place... A PCB fiducial is a landmark. The fiducial tells the machine where the board is located in the machine. A single fid can only deter
Electronics Forum | Thu Feb 18 22:49:49 EST 1999 | Chris G.
| We are using .040" diameter fiducials (global and local) on our boards. They are solder covered and HASL. I get batches of boards where the p&p vision system has trouble reading the fiducial. The fiducial looks dark on the screen. The board ven
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