Electronics Forum | Tue Aug 09 13:25:24 EDT 2005 | pr
From what I can gather, the annular rings are used for grounding when these boards are put in housings. A screw goes through the hole and is torqued down. If there is excess solder on the annular ring, the screw doesn't seat properly. The pallets cov
Electronics Forum | Fri Aug 15 00:51:30 EDT 2008 | boardhouse
Hi Paul, My discloser, I sell for an offshore house, this is Crap.... Section 3.4.3 Annular Ring (External) of IPC-6012A, which also calls out Table 3-5, states that "Plated-through holes identified as vias can have up to 90 degrees breakout of t
Electronics Forum | Thu Jun 28 08:24:34 EDT 2001 | Steve Vargas
Herb: Try oversizing your stencil fiducial openings to maybe twice the size of the board fiducial. When aligning manually, look for uniformity in the annular ring which appears around the fiducial. Hope this helps.....
Electronics Forum | Tue Dec 17 17:22:45 EST 2002 | Tim Marc
Thanks Russ. You were right I looked one page too far. We can meet (A,B,C,D). To meet the 75% of (E) the annular ring will have to be scraped. Your help was much appreciated.
Electronics Forum | Wed Apr 15 10:27:20 EDT 2009 | mbohuslav
I am trying to find out what would be considered the minimum test via that would be considered reliable for Flying Probe testers. Specifically Javelin testers. Also what would the minimum annular ring need to be.
Electronics Forum | Wed May 09 11:25:29 EDT 2001 | medernach
What type of preheaters do you have on you're wave? I have to agree with Dave. Your leads are not cold, they are hotter than the annular ring on the PCB. This would cause the solder to go to the lead only rather than the component and land pad / a
Electronics Forum | Wed Jul 20 15:05:28 EDT 2005 | Fred M.
With the new rev D release of IPC-A_610 came a new section 10.2.9.3 which identifies a via (through hole) with nicks along the inside of the annular ring. Defect is all three classes and states "Damage to conductor or lands". We have for years defa
Electronics Forum | Thu Feb 12 17:14:49 EST 2004 | Jim
Replying to mine own thread for clarification. We are having some issues with solder mask shifts on memory boards using fine pitch BGAs. At times the etch to etch distance does not leave room for a solder mask annular ring to be shifted or it will c
Electronics Forum | Tue May 10 10:30:57 EDT 2005 | HOSS
One failure mode we have seen with TH XTALs is shorting from one of the leads to the metal can that houses the part. Typically, the opening around the lead at the base of the part can be small and if you combine this with a larger than needed annula
Electronics Forum | Fri Apr 27 10:55:54 EDT 2007 | Brett
Pete, is there a probe-style that will accomodate a via that's filled, but a little concave (inward) fillet? The ICT personnel complains about this scenario too. I'm not an ICT person, but I do know that there are pogo pins that have a crown (for t