Electronics Forum | Fri Oct 23 15:43:31 EDT 2009 | seankim10
According to 5.2.6.1, it states that defected if Solder balls are not entrapped in no-clean residue or conformal coating. How do you define entrapment or how do you assess if the balls won't dislodge under normal product service environment? The sold
Electronics Forum | Mon Sep 21 20:45:55 EDT 2009 | davef
10.4. Pre-Cure Examination. Immediately after material application, the uncured conformal coating shall be examined for: a. Bubbles and Air Entrapments. These defects shall be broken by vacuum, with a sharp probe, or other appropriate tools. b. Bridg
Electronics Forum | Thu Jan 31 13:01:33 EST 2013 | kmots15
Defect if its not coated. Defect - Class 1,2,3 • Solder balls are not entrapped, encapsulated or attached or can become dislodged in the normal service environment. • Solder balls violate minimum electrical clearance.
Electronics Forum | Thu Nov 30 21:30:00 EST 2023 | ritronusa
Having issues with getting the right formula for a GPD simplecoat machine. We tried a silicone that hardened in our lines and when we try acrylic it is either showing air entrapment or cobwebbing.
Electronics Forum | Wed Mar 27 18:23:01 EST 2002 | kmorris
Does anyone have experience doing conformal coating over Plastic BGA in High-Rel PCB assembly? Is underfill necessary to avoid problems with entrapped air, etc? Our application is a 17x17mm BGA, 256 I/O. We are assembling with a water soluable pas
Electronics Forum | Tue Nov 30 16:50:20 EST 1999 | Dave F
Greg: It depends on the specifics of the flux you are using. You didn�t say. Generally, using a: � "No-clean flux" should create no flux entrapment problems for most applications. � RMA with 25% or more solids as a "no-clean" should create no flu
Electronics Forum | Wed Mar 27 21:20:30 EST 2002 | davef
There is two major BGA coating camps. * Camp #1: "We require the coating to be under low stand-off devices but with no filleting. So we apply a thinned dip coat first, and then top-off with a proper spray coat" * Camp #2: "We want no coating under th
Electronics Forum | Wed Oct 02 12:06:59 EDT 2002 | dragonslayr
Scott - all sounds good. My primary concern is the residual flux left behind under the BGA. Will moisture entrapment become a concern over time? I believe that may be dependent on the flux formulation. I know that some no clean fluxes actually become
Electronics Forum | Thu Dec 22 21:29:05 EST 2005 | davef
Josh: Room Temperature Vulcanizing (RTV) is Dow Corning's trade name for it's family of silicone cure sealants. RTV is about the worst kind of coating there is. Its chemistry is highly ionic and it requires atmospheric humidity absorbed to "complete
Electronics Forum | Tue Dec 08 17:55:51 EST 1998 | Dave F
1. What is the best way to remove polyurethane conformal coating from selected areas? Your conformal coat material supplier is best equipped to tell you how to remove the coating. Polyurethane conformal coating is not easy to remove. Without in-pu