Electronics Forum | Thu Jun 13 21:44:21 EDT 2002 | jkhiew
Hi all, * Defect : termial to terminal touching btw two melfs body that created short circuit. * Clearance : 0.8mm btw two melfs body. * Size melf : diameter=2.4mm to 2.7mm, length=4.8mm to 5.2mm * Stencil opening : "v" shaped to minimise component
Electronics Forum | Fri Feb 20 08:56:42 EST 2004 | davef
We successfully clean WS flux on 1mm and 1.25mm pitch BGA. For 0.8mm pitch BGA, we use no clean, because we cannot remove the flux residue from under them efficiently. Use ion chromatography testing to be sure it is clean under the BGA. IC is the on
Electronics Forum | Thu Jun 24 20:28:58 EDT 2004 | needhelp
We design PCBAs. Our CM assembles the boards for us. So far we have used waterwash SMT process to build the boards. Accidentally, due to documentation errors, we suddenly have a huge batch of boards built with No-Clean process. Although the boards pa
Electronics Forum | Thu Jun 09 03:16:06 EDT 2005 | PSGill
I'm using Kester R520A Lead free solder paste. The flux % stated on the Certificate of Analysis(COA) when the product delivered to us is 10 %. The tolerance is 1%. But when i send the jar to an external lab to determine the flux % it is more than 11%
Electronics Forum | Wed Jul 27 17:01:14 EDT 2005 | Dreamsniper
Issue: At 60'C test PCB Fails. Operator did simulation. Use of Heat Gun to heat up the BGA to 60'C while PCB is powered and running. At 60'C BGA fails. When pressed system is back which means that something becomes open. Sent BGA for SEM and found t
Electronics Forum | Wed Dec 06 21:28:12 EST 2006 | davef
It's worse than just using the test equipment manufacturer guidelines. Along with that, you have to deal with each of the test fixture fabricators' preferences as well. What this boils down to is a negotiation with the test engineering group as to w
Electronics Forum | Wed Jul 29 07:26:12 EDT 2009 | dilogic
Hi Patrick, thanks for the response. I might add some more information - we succesfully soldered some boards with the same settings of belt speed, pre-heat temp. etc. This batch of boards differs from the previous in a way that they are 4-layer. May
Electronics Forum | Wed Jul 18 14:35:56 EDT 2012 | kruzer
I can not send or receive proper of the machine, also i cant send or recive program. on the second computer I have, "ESMT 1.0.1," there without any problem computer communicates with the machine, but this is an old program and wants to have everythin
Electronics Forum | Thu Jan 09 15:19:41 EST 2014 | davef
For a typical wear surface application [millions of wipes], I agree with hege. You need to be talking electrolytic gold, NOT immersion gold. IPC-2221 says something like ... For edge connectors and areas not to be soldered: * Nickel - 2.5um [~100uin]
Electronics Forum | Mon Jul 25 04:49:28 EDT 2016 | chris10
Hi, To enlarge the 3.6 V of PWM wave of MCU to 6 V which control on and off of transistors. But op-amp part never amplifies out . Simulation diagram is shown in the figure. Op-amp is LM368h and 8 v single power supply.The datasheet of LM368h is http:
