Electronics Forum | Tue May 27 12:53:15 EDT 2003 | davef
Our solder irons are tuned to 700*F, but the in-use temperature varies according to the solder alloy and the characteristics of the board and components. Check some of the papers on multilayer ceramic capacitors. They get fairly specific, for insta
Electronics Forum | Mon Apr 12 10:39:48 EDT 2004 | Ron Herbert
Correct preheating of the assembly is critical. Check with your flux manufacturer regarding the recommended topside pcb temperature as it enters the first wave. It is important that this temperature be achieved without burning the flux on the bottom
Electronics Forum | Fri Jul 18 05:09:40 EDT 2003 | Evtimov
Hi, I see it's easier to use a few profiles. Simply and easy! But my advice is to make own profile for each board.The thickness is ok but there are other characteristics you miss that way. Even board material is not the same. If someone tells you t
Electronics Forum | Wed Sep 03 18:20:00 EDT 2003 | davef
Major advance: Productionization of SMT. Minor advances: * Realization and control of solder paste characteristics * Vision alignment controls in printers. * Evolution from mechanical centering [through laser alignment controls] to vision alignment
Electronics Forum | Fri Mar 19 14:31:43 EST 2004 | pdeuel
DI water de-ionized water is an easier way to ensure washing free of contaminates. De-ionized water has a characteristic resistance of 18 meg ohms per cm squared. Resistance monitors can be installed in cascading wash systems that would monitor conta
Electronics Forum | Tue Apr 13 10:30:52 EDT 2004 | Ken
Threre has been speculation as to voiding as a function of solder paste liquiduous vs. ball liquiduous. Gas entrapment is thought to result if one melts before the other (I forget which order). Two profiles may yield different results as determined
Electronics Forum | Wed May 12 06:57:00 EDT 2004 | davef
You say you have lots of problems with a BGA, tell us about: * Specific problems you see. * Solder paste supplier�s recommended profile. * Temperatures measured on the problem ball[s] of the BGA during reflow. When you say �u1 BGA�, what do mean? W
Electronics Forum | Mon Jun 28 22:12:24 EDT 2004 | davef
Things to consider are: * Thermal expansion characteristics of you flex and your pallet should be better matched. We use G-10. * Placement of your two sided tape should be better, more uniformly distributed. We run strips the length of the flex that
Electronics Forum | Thu Sep 02 15:51:15 EDT 2004 | cburress
All: IPC does not directly state any criteria for physical characteristics of what a filled via should look like when embedded within a surface mount component's pad. I am using several of these in my design, and have received PCBs that exhibi
Electronics Forum | Tue Feb 22 07:19:51 EST 2005 | austinj
I have been profiling with the fixture. I have performed multiple DOE runs and came up with the following with success: Cooled soak zone to max 150C for approx 100sec. and spiked reflow zone for max temp of 230C, pcb/panel is above 183C for 64sec.
