Medical Electronics Assembly
‘Checking Up’ on Medical Electronics
Medical electronics assembly demands a different set of criteria than do commercial PCBs. The US FDA requires specific documentation, especially for verification of certain processes. Today’s medical electronics assembly also requires special testing, avoiding obsolete components and a detailed evaluation of a Pb-free product, as a looming EU RoHS Directive is expected to include medical electronics.
By Zulki Khan
Solder Ball Attachment Using Laser Soldering
Reballing BGAs due to rework and conversion from RoHS-compliant solders to SnPb (or vice-versa) typically requires subjecting the component to additional reflow cycles beyond component manufacturer recommendations. Laser attachment or laser reballing in an oxygen-free bath eliminates two additional temperature excursions and provides improved component reliability by facilitating the use of standard assembly reflow temperatures without mixed alloys.
By Joshua Muonio and Richard Stadem
Improving QFN Reliability
The proper amount of solder is needed to ground the bottom of a QFN package and simultaneously create a toe fillet. Too much solder on the ground plane can cause parts to float; too little means insufficient grounding. This article focuses on the toe fillet and bottom connection, which create a kind of two-pronged connector, providing electrical continuity from both points.
By Joseph G. Ameen and Gilson V. Geralde
Doing business, the standard way.
Design Chain Associates’ Mike Kirschner.
Outsourcing gets medieval.
One size doesn’t fit all.
A mask for all seasons.
Optimal oven conditions.
Ursula Marquez de Tino
Reworking Pb-free PCBs.
American Competitiveness Institute
Test and Inspection
ICT gets probed.
Stacy Kalisz Johnson
Cleaning becomes an event.
Pb-Free Lessons Learned
The tenacity of Pb-free residues.
Adding solar cells to the SMT line.
Eastern Advances (1.38 MB PDF in Chinese)
On the cover: A laser reballing process can cut two temperature excursions. (Photos courtesy General Dynamics)