Electronics Forum | Thu Jul 15 17:53:34 EDT 1999 | Boca
| I'm designing a board where the parts will only fit if I do one of the following: | | 1. Put BGAs on both sides | | 2. Put BGAs on top, smt TSOPs directly underneath and using blind vias to keep the real estate on the bottom side below the BGA pa
Electronics Forum | Thu Jul 01 13:57:57 EDT 1999 | Kris Wiederhold
| Dear guys, | | I have some problem on assembling micro-BGA with solder paste (63/37). The micro-BGA we assmeble is 0.75mm pitch and with 45 pin (solder bump is 96.5/3.5Ag). The stencil is a laser-cut stencil with 5 mil thickness. We are now usin
Electronics Forum | Sun May 16 10:11:50 EDT 1999 | M Cox
| I'm running memory module product- SMT double reflow ( 12 modules per panel). I'm using the epoxy base solder paste in order to reduce the flux spattering problem onto the gold finger which could lead to the intermittent contact problem. | | I do
Electronics Forum | Sun Apr 25 11:37:51 EDT 1999 | Earl Moon
| We are just starting to manufacture a PCB with a .039" fine-line PBGA. We are currently seeing voids, mainly in the center, that are as much as 45%. We also intermittently see the corner balls of the PBGA smaller than the center balls. We are using
Electronics Forum | Tue Mar 23 04:07:44 EST 1999 | Scott Davies
Rob, We are also using intrusive reflow to simultaneously process SMT and Thru-hole components. Our arrangement goes as follows: - Screen print solder paste to the single sided PCB using 0.008" laser cut stencil. - Apply adhesive dots to selected
Electronics Forum | Thu Mar 25 14:00:45 EST 1999 | Bob Willis
| Rob, | | We are also using intrusive reflow to simultaneously process SMT and Thru-hole components. Our arrangement goes as follows: | | - Screen print solder paste to the single sided PCB using 0.008" laser cut stencil. | - Apply adhesive dots
Electronics Forum | Fri Feb 19 09:14:52 EST 1999 | Justin Medernach
| During inspection and test we find leads which do not get soldered. Some are because of insufficient paste, but with others everything looks right. This will only happen on 1 to 2 pins, and it is not isolated to a specific type of ic or location o
Electronics Forum | Sat Feb 20 23:08:36 EST 1999 | GORDON DURPHEY
| Hey all- | | My question is this: My stencil printer operator has said that he has to | wipe our 6-mil stencil each pass to get the paste in the 20-mill pitch | aperatures for a QFP to release well. We are using Amtech NC-559 type 3 | paste with
Electronics Forum | Thu Dec 24 08:44:25 EST 1998 | Earl Moon
| | | | Folk's, | | | | I'm in need of some help / direction. I'm working on my thesis for a masters based on looking at the effect's of the solder resist promoting / reducing the amount of solder ball's during wave. I'm looking at thing's like colou
Electronics Forum | Tue Dec 01 10:25:54 EST 1998 | Earl Moon
| | | All y'll: I could use your input on determining when to skim dross from a wave solder pot. | | | | | | On one hand, dross protects the surface of the solder from oxidation. On the other hand too much dross may affect solder joint quality. O
