Electronics Forum | Fri Feb 20 13:01:26 EST 2004 | Jay
First, it depends on the alloy composition of the solder. As you might know, eutectic Sn/Pb solder has the lowest melting point among available conventional solder systems. (except those based on Sn-In and Sn-Bi systems.) For example, 63Sn/37Pb - 183
Electronics Forum | Mon Apr 12 09:36:57 EDT 2004 | wgaffubar
Russ, These are the pb free components that you mentioned that are coming around the bend. Not the old CBGA's. I use to use CBGA's alot with former company. These are 15 x 15 mm plastic BGA's with 14 mil pg free solder balls going on 8 mil gold pads.
Electronics Forum | Wed May 19 07:38:42 EDT 2004 | Bob L.
I'm trying to help one of our remote sites solve a problem with a warped PBGA. The corners are lifted, creating columnar joints and the central balls are sometimes shorting. I've verified that it's not popcorning and I've got samples going to the l
Electronics Forum | Thu Dec 22 12:05:37 EST 2005 | Tony
Currently we are using a 2 step vapor soldering process to manufacture our std. lead soldered parts. The first step was done with a ls240 vapor fluid and the second was done with a ls200 fluid. Using a 221 deg C sn95/Ag5 solder for the first step a
Electronics Forum | Wed Jan 17 09:32:09 EST 2007 | Jeff
Hi, I am having problems reworking a lead free PBGA (23mm x 23mm, 1mm pitch). The board is relatively small (5" X 4" X 0.063"). During the removal stage, a thermocouple was placed at the solder ball level (between the board and underneath of compo
Electronics Forum | Tue Jul 01 12:35:18 EDT 2008 | amcross
Please accept my apologies for being offtopic. I have tried posting on the career center, and our job even appeared at the top of the most recent smtnet email newsletter. Still, we received essentially zero response. I'm hoping maybe a post here mi
Electronics Forum | Mon Aug 25 15:40:58 EDT 2008 | dyoungquist
I am seeing poor quality solder joints, mostly on 0402 components. The problem is that while the pad on the pcb is getting fully wetted, the solder is not flowing up the sides of the 0402 component, i.e. the 0402 lead is somewhat de-wetting. The re
Electronics Forum | Tue Dec 24 09:34:55 EST 2013 | emeto
Hi, it is a not given clear here. I will tell you some basics about the profiling: 1. Profile stages A. Preheat - the board preheats from room temp to 130-150C depending on the paste B. Soak - 150-170(or other range depending on the paste). here th
Electronics Forum | Mon Sep 24 12:58:31 EDT 2018 | vincentl
We are attaching 0.50mm diameter SAC 305 solder balls onto 0.38 diameter Au plated pins placed at a 0.80mm pitch (pins are pressed into a plastic insulator). A tacky flux is then stenciled onto the pins using a stencil with.a 0.38mm diameter aperture
Electronics Forum | Tue Aug 03 17:28:33 EDT 1999 | DLKearns
| | | I have been asked to supply a maximum shelf life for our assemblied PCB's. I realise this is dependent on so many factors- temperature, humidity, no of layers etc. But does anyone have a formulae for calculating shelf life, or does anyone know