Electronics Forum | Wed Feb 05 13:08:20 EST 2003 | joeherz
You're correct that a thicker solder deposit will make bridging on fine pitch devices a bigger risk. Another alternative could be to slightly over-print the pads (onto the soldermask) ala pin-in-paste process. Basically adding enough solder to fill
Electronics Forum | Thu Feb 27 16:38:01 EST 2003 | russ
James, The last time I evaluated in-line cleaners (2 yrs ago)the Aquastorm was by far the best. They were the easiest to maintain, acheived the highest cleanliness level (per in-house testing with omegameter 600 heated solution), and were the quiete
Electronics Forum | Tue Mar 04 18:05:03 EST 2003 | msivigny
Hello Maribel, One way you justify the use of an AOI is to calculate how many defects the system will potentially detect before reflow, associate a repair cost per defect and make the calculation. For an AOI to be effective in this regard, it must sc
Electronics Forum | Fri Mar 07 21:02:21 EST 2003 | neil
When printing below .5mm pitch, the recommended stencil thickness is 5Thou, laser cut. Do not use any reduction and ensure wherever possible the pad to space ration is 1:1, the length of the pad is not as important as the gap between adjacent pads. T
Electronics Forum | Mon Apr 07 09:52:07 EDT 2003 | kmorris
I have just started an assembly which uses a 16 mil pitch QFP. We ran on Saturday, using a type 3 solder paste. (working Sat's really sucks) We really struggled with paste release after the stencil sat for 15 minutes without printing. Apertures clog
Electronics Forum | Thu Apr 10 03:29:16 EDT 2003 | emeto
Hi, that post sounds very bad.But I thing you shoul make an order for that problem.First the problem as I can see is not single.If I am right you should do exams step by step: 1.Design of the board-examine very carefuly(ask the manifacturer for help)
Electronics Forum | Wed Apr 16 13:19:13 EDT 2003 | Takfire
Thanks Russ! The origianal complaint from the customer was in regards to what appeared as "bumpy" appearance and "holes" in the solder fillet. This problem was originally presented as an appearance issue only. Further investigation by our DPA lab r
Electronics Forum | Thu Apr 17 13:00:28 EDT 2003 | Takfire
Russ, The caps are 0603 case size. I am not sure about the manufacturing details, as I work for the capacitor supplier. The manufacturing details are unclear at the moment, as the customer (South of the border) has not released such detailed inform
Electronics Forum | Sat Apr 26 20:27:18 EDT 2003 | LWEI
I'm working on a protobuild for a pcba. THis pcba uses double-reflow, paste-in-hole process. On bottom side there is a Ceramic BGA, size 35 X 35 mm, thickness 6mm, over 900 balls count (ball pitch 1mm)and it weighs a hefty 20 grams. Printing uses 6 m
Electronics Forum | Tue Jul 01 17:38:24 EDT 2003 | jartman
I've faced this several times in the past, and the only real solution is to wirebond before SMT assembly. Everything leaves a residue, and trying to clean a residue off later is basically hopeless. This may require some trickery in your SMT process
