Electronics Forum | Wed Mar 25 16:36:10 EST 1998 | Steve Joy
We have successfully put .016" vias in .030" pads. There is no drain off with .030" solder balls, since the actual volume in the .002" depression is low. We did notice random bubbles where, apparently, the solder reflowed and trapped the air in the
Electronics Forum | Tue Jul 31 17:11:28 EDT 2007 | rpadilla
Is the via hole not supposed to be there, or is this by design? If you are trying to fill the via hole with solder and not have voiding issues, I suggest using a type 4 solder powder mesh size. Reason being, anytime you go beyond Type 4 mesh, to so
Electronics Forum | Mon Apr 02 20:47:22 EDT 2001 | davef
Cuppla questions for ya ... Where are the shorts [above the mask or between the mask and the laminate]? On the board, what material is between the copper traces and the mask? What type of solder mask(s) used by your suppliers? What are they using
Electronics Forum | Fri May 15 18:18:51 EDT 1998 | Earl Moon
| Help! | We have been doing some trials on Paste Through Hole and have encountered a problem. The screen is designed (as is suggested in technical info re PTH) to give double the paste volume required to fill the void between the pin and via. The
Electronics Forum | Sun Dec 09 22:54:20 EST 2001 | dburr
It sound you have already discovered to root cause, flux entrapment in the via holes. Short of changing the desing, here are sone suggestions. The main thing is you have to dry out the via holes of the wet flux. Some things to try are: slow down t
Electronics Forum | Fri Sep 08 21:49:24 EDT 2017 | sbar5781
Hello, I have a few PCB boards i am trying to be manufactured that are miniaturized medical devices. Thus they require IPC Class 3 Specs. However as miniature devices they have limited space, including a 0.4mm pitch BGA socket, which currently has
Electronics Forum | Thu Jun 25 14:33:51 EDT 1998 | Chry
| Hi there Chris! | Are the leads you talking about fine pitch? Is the complete fillet attached to the foot, with it being cleanly separated from the pad? I bet if you look at the board there will be via's really close to the pads at the location
Electronics Forum | Mon Feb 23 23:50:18 EST 1998 | mike
| Does anyone have any experience with via in pad for | BGAs using conventional thru hole technology? | Steve Joy Steve, I had a customer who had designed a board to use a BGA socket. Well the socket did not work out so we then placed the bga dire
Electronics Forum | Tue Jul 06 18:16:14 EDT 1999 | Boca
| | Is anyone aware of some guidelines regarding through-hole in SMT pads? One of our designers wants to add through-hole leads in some SMT pads for an inductor. The size of the hole is 0.032 inches and takes-up approximately 25% of the pad area.
Electronics Forum | Mon Jul 26 18:05:18 EDT 1999 | ScottM
| Presently protos of micro-bgas (80i/o) pitch .030/.031 | 12BGA per assembly | | The board is a (.062, 4 layers) FR-4 using Dry film | Pads .014inch | Vias within footprint .020inch | Vias to be filled by bottom side(solder side) only .030in dia. F
