Electronics Forum | Thu Apr 11 19:12:11 EDT 2002 | djarvis
Sorry fellas -disagree. We only clean our stencils in the ultrasonic machine at the end of the run. If the same pcb is up the next day we clean them by hand. We use Electrolube SSS and the used rolls from the in line under stencil cleaner. Wipe the
Electronics Forum | Tue Mar 29 03:03:42 EDT 2016 | wesleyintelli
Our MPM UP100 is not slowing the pcb carriage as it is brought under the stencil. The result is that the carriage jolts the machine heavily when it is fully loaded. The hall effect vane sensor half way along the rear rail is working correctly. The le
Electronics Forum | Tue Apr 27 16:49:16 EDT 2004 | davef
Where blank are the balls on a BGA supposed be? UNDERNEITH, dammit!!! Fire that inspector. It's good that you have your balls imbedded in something, so that they are not rolling around. Beyond that, consider the five ball system! - No more than
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 | Mon Sep 19 09:16:24 EDT 2016 | markhoch
Hi Shriram, Are you saying that there is a trace running between the pads for this 0603 capacitor? If so, this design may be causing a gasketing issue between the stencil and the PCB. The uneven height prevents the stencil from sitting flat on the PC
Electronics Forum | Thu Sep 01 09:05:47 EDT 2005 | russ
Thermal pads located underneath leadless devices require a 50% reduction in the stencil aperture.
Electronics Forum | Wed Aug 31 12:49:04 EDT 2005 | kmeline
I have been having the same problem with the LLP. I have three stencil I have done reduction on. The first I went by the manufacturing recommendations. The last two I have done more reducing for the thermal pad. The last one was at a 20% reduction an
Electronics Forum | Thu Sep 11 15:23:31 EDT 2003 | Peter L.
I have come across a rash of failed assemblies that have 0805 capacitors and resistors, bottom side glued, wave soldered and washed. Trouble shooter reported touching up the solder joints on a few areas and the boards would pass test. I had a look a
Electronics Forum | Fri Jul 20 13:50:22 EDT 2018 | vchauhan
This question is regarding stencil design: I am having voids under QFN TI P/N LMZ20502SILT. I have attached component pic. Signal pin is 18X16 mils. Center pads are 31 mil sq. Initially I had stencil done with one mil per side reduction on signal pad
Electronics Forum | Thu Jul 26 04:26:59 EDT 2018 | Robl
Hi VChauhan, I'll preface this by saying I am no DaveF. Voiding can occur when the flux in the paste boils and vapourises, the expanding vapour needing somewhere to go displaces the paste. So... what we have done in the past: 1) Step the stencil d
