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Plan Ahead for BGA Device Upgrades
BGA Socket Adapter Systems convert surface mount device packages to through-hole (pinned) assemblies, making it easy to plug and unplug SMT devices in the field or the test lab.
Advanced Interconnections Corp.
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Maybe it's the thermocouple connection
If your thermal profiling readings seem inconsistent, the culprit could be your thermocouple attachment method. A recently conducted study revealed some interesting findings.
ECD
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November 25, 2009 - Updated
November 23, 2009 - Originally Posted
Cause of Yellow/Brown Discoloration
What is possible cause of "yellow/brown" discoloration on a silver immersion circuit board assembly after the oven reflow process?
G. G.
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| Expert Panel Responses |
Yellow / Brown color on silver is silver tarnish which is a combination of silver sulfide and silver oxide which occurs over time as silver is exposed to air. Heat accelerates silver tarnishing, so it is easily visible after the first reflow cycle. Unfortunately silver tarnish can cause solderability issues and subsequent reflow or wave soldering may be difficult.
Mike Scimeca
President, FCT Assembly
Mike Scimeca created FCT Assembly after the purchase of Fine Line Stencil, Inc., and consists of two major operations: stencil manufacturing and the manufacturing of electronic assembly products such as solder paste, flux and solder bar.
The possible cause for yellow/brown discoloration are the flux viscosity and the reflow profile. You need to check the flux property like activation temp, viscosity, helide contains in the flux and temperature profile of soldering.Also check the amount of flux apply to the solder joints.
Sandip Thakor
Quality Engineer, Matrix Telecom Solution P Ltd
Sandip Thakor has 9 years of experience in electronics industry specializing in soldering technology. Thakor has experience in lead free installation, process optimization and developing quality standards.
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RAIG Minimizes Corrosion, Allows Higher Gold on ENEPIG
Paper describes a mixed reaction RAIG electrolyte that minimizes galvanic corrosion and allows higher ENEPIG gold thicknesses, enabling robust designs and world-class quality on target with minimal variation.
Uyemura
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