Electronics Forum | Thu Aug 17 16:12:48 EDT 2000 | John Maxwell
We are using a water wash paste for our boards which is leaving ionic contamination ( salts). In the presence of low humidity levels this creates the effect of a capacitor. Our product which is test instrumentation does not calibrate. I am lookin
Electronics Forum | Fri Apr 04 09:28:59 EST 2003 | davef
Q1: Anyone has any ideas on how this post-SMT reflow solder joint could have changed to whitish joint? A1: Dunno. You need to tell us more. For instance: * What is the appearance of this white residue? [eg, glassy / coarse, milky colored / opaque,
Electronics Forum | Wed Aug 13 18:12:20 EDT 2003 | Carol
Has anyone tried to get conformal coating under a BGA? (large package MPC555). There is a concern with ionic/metal bridges developing between contacts due to accumulation of dust/humididty. Final product is Class 3 (aerospace). Thanks, Carol
Electronics Forum | Wed Jul 14 15:24:57 EDT 2004 | Jarmato
You may also want to investigate an Ionic contamination tester. You can check with Alpha, Westek or an equipment broker to find a used tester. If you switch to OA fluxes this will be an important test to perform on a regular basis.
Electronics Forum | Fri Oct 29 17:44:13 EDT 2004 | davidcb
Davef, thanks for inputs. I think your correct, we have since obtained some ionic analysis and sure enough there is relatively high chlorides on the bare pcbs. The toluene is controlled within dip tank / drying system, almost no exposure to workers.
Electronics Forum | Thu May 26 19:32:13 EDT 2005 | Mike Konrad
Three popular methods: Resistivity of Solvent Extract (ROSE) Test Method IPC-TM-650 2.3.25: The ROSE test method is used as a process control tool to detect the presence of bulk ionics. The IPC upper limit is set at 10.0 *g/NaCl/in2. This test is p