Electronics Forum | Thu Feb 18 12:56:18 EST 1999 | Bob Barr
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 vendo
Electronics Forum | Fri Sep 27 10:54:55 EDT 2002 | yngwie
Thank you pr. It was much appreciated. Is this mark normally act like a global fiducial/local fiducial for mBGA ? Is this a standard mark that can be read by the placement machine? what is the typical size of this mark ? are they masked ? thank y
Electronics Forum | Mon Mar 01 16:26:38 EST 2004 | rhdez
Is this problem with local fiducials or global? Is the problem on the same equipment? Is this a cad file o centroid? How are you measure the coordinates?
Electronics Forum | Tue Jun 14 07:29:12 EDT 2005 | jdumont
So I set up a board yesterday and did a test run. It appears that the spacing does matter on my machine. It placed the part off-center the same amount as one of the fiducials. Im going to look more into fixturing and placement pressure adjustments I
Electronics Forum | Thu Feb 16 02:50:24 EST 2012 | fadzril
In current conditions with new high tech machines, the requirement for having local fiducial marks can be dropped. Plus, using the fiducial marks of course will improve the mount accuracy, but will increase the cycle time. Compare both conditions & s
Electronics Forum | Fri Jun 10 14:41:45 EDT 2005 | jdengler
I agree with PR. We run down to 12 mil pitch with out local fids. We run with 2 global fids for a panel of up to 40 boards. This has worked very well for us. Jerry
Electronics Forum | Thu Oct 19 13:14:34 EDT 2006 | lgroves
While I can only speak for Samsung equipment I believe that this would not be a problem for most modern machines as the local fid positions are usually programmable
Electronics Forum | Thu Oct 19 14:32:53 EDT 2006 | curious
The fid is just a "known reference" location, the only advantage/difference is proximity to the part. It almost sounds like you are using the local fid as your part placement coordinates? So maybe the CS machine IS different but something doesn't sou
Electronics Forum | Thu Oct 19 14:49:35 EDT 2006 | sliebl
We teach all of the fids. Globals and Locals. This is because we use a magnetic table, not a pass through conveyor. Without showing the machine the global fids, it has no idea where we've mounted the board.
Electronics Forum | Thu Oct 19 15:15:24 EDT 2006 | russ
to use local fids such as this you must use the cad data, when the machine knows where it is supposed to be and seeks there it reads where it (PCB) really is and then corrects the machine, it does not have to be symetrical at all. If you teach fids
