Electronics Forum | Thu May 13 18:36:55 EDT 1999 | Andrew Wulff
| | On 1.27mm (0.050 inches) Standard Ball Grid Array's. | | The ball size diameter starts at approximately 0.025 inches. | | | | If the ball size decreases to 0.012 inches (due to the solder flowing down a via) is the solder connection reliable? |
Electronics Forum | Wed Jul 09 10:15:57 EDT 2008 | aj
I have carried out some further measurements on the device and the results are as follow: Component Lead width measures 183 microns. Actuals PAD width measures 158 microns. What I am thinking is that the lead is attracting the solder hence prevent
Electronics Forum | Mon Apr 05 14:57:59 EDT 1999 | Alvaro Carrillo
Hi, Somebody know how to calculate the size of pads for different IC's: QFP's, SOIC, SOJ, etc. any help is apreciated. thanks AC
Electronics Forum | Thu Dec 28 12:19:20 EST 2006 | slthomas
So I'm the only one that's had crappy piles of silkscreen between pads?
Electronics Forum | Thu Jul 10 07:48:40 EDT 2008 | realchunks
Try IPC SM 782. Also most parts manufacturers should be able to provide you a pad design.
Electronics Forum | Tue Jan 02 09:47:41 EST 2007 | slthomas
We had a supplier that put a [fuzzy and of variable height) line of ss between all chip R and C pads. Of course we were in low cost mode and had purchased a year's worth of boards.
Electronics Forum | Mon Jul 07 13:33:40 EDT 2008 | realchunks
Most QFP 128s have a 0.16mm wide lead. Might have to modify your pads if you'r buying some odd ball part. But generally 0.2mm should be OK for this part. You may never get good toe wetting. Most QFPs are cut apart after plating, thus the toes are
Electronics Forum | Mon Jul 07 11:46:29 EDT 2008 | aj
Hi All, Can anyone advise the spec for land size of a lead 0.2mm in width? I am placing a TQFP128 0.4mm pitch, the leads seem to be wider than the actual pads they are been placed on? I am also experiencing poor wetting on this part , it has NiPdAU
Electronics Forum | Fri Sep 05 06:17:36 EDT 2014 | edriansyah
Hi, We have a problem with our BGA Pad. Our PWB manufacturer make the BGA Pad in irregular form. some big, some small. Please see the picture on attachment. BGA Detail BGA Pitch 0.5 mm BGA Ball 0.3 mm BGA Pad (big) 0.2 mm (as per gerber) BGA
Electronics Forum | Sun Sep 07 13:33:50 EDT 2014 | horchak
Edri PCBA design and pad geometry is one of the critical factors for BGAs. Typically the pad size for collapsible balls is 80% of the ball diameter. Pad size consistency is critical. In your situation what will happen the larger pads will wick the s