Electronics Forum | Fri May 15 13:17:18 EDT 2009 | tomsmiley
We implemented an inexpensive home dishwasher solution last year for cleaning assemblies. It works very well for both lead free and tin/lead cleaning. DI water at room temp is all we do and the boards come out squeaky clean. We had to use the least
Electronics Forum | Wed May 20 17:00:56 EDT 2009 | dyoungquist
We just placed a 56 pin QFN, 1 per board, on 10 boards and had zero defects. A good paste job, proper placement and a correct oven profile are the keys. If these are set up correctly, on larger runs your defects won't be zero but they should be le
Electronics Forum | Wed May 20 17:18:09 EDT 2009 | daxman
Just out of curiosity, how are you or anyone else determining a defect? Last I checked, IPC had no criteria yet for solder defects for QFN components. Has this changed? Biggest problems we see are voids which our x-ray shows a lot of. Our problems
Electronics Forum | Fri May 22 08:04:30 EDT 2009 | stevezeva
Have any of you ever worked with Actel's QFN 180? A three row I/O QFN? Actel has a published paper on design and assembly guidelines, but we're finding that they are pretty much generic, and don't really work as well as they lead you to believe. ht
Electronics Forum | Tue May 26 15:39:16 EDT 2009 | mikesewell
Amkor's MLF guidelines are very similar to Actels. 1 to 1 on the stencil to part pad on the I/O pads, 75% with a grid windowpane, 0.125 mm/5 mil stencil. For example, the Actel area ratio for a 0.3 mm sq. pad and 0.125 mm stencil is 0.6 which seems
Electronics Forum | Sun May 17 00:41:17 EDT 2009 | microdot
hi, I am sorry if i sound offended anybody. What i meant is that we are handling boards which are from major manufacturers like hp / compaq / dell / ibm / intel. So if annybody has experience of handling it..than they may have reflow profiles of sa
Electronics Forum | Tue May 12 21:51:23 EDT 2009 | dynamicsource
I just want to check with you guys, those who have Heller reflow oven and has lifetime warranty if warranty is still lifetime. We were told that warranty for blowers and elements are now just limited to 8 years, though when the machines were bought,
Electronics Forum | Fri May 15 19:20:47 EDT 2009 | jlawson
if you have a budget for new machine, laser depanelising is pretty good for flex PCB as no physical stress on PCB like mechanical routing, thus fixturing is easier and less prone to moving the flex while cutting. Laser systens can also cut FR4 standa
Electronics Forum | Fri May 15 01:44:50 EDT 2009 | dilogic
Since UIC does not support older machines anymore, is there another way to upgrade our GSM1? We have an I-block hardware running OS2.11 and USOS 1.4.14. I would like to upgrade to USOS 3.xx, to be able to use Enhanced Product setup feature. Any hints
Electronics Forum | Fri May 15 10:04:59 EDT 2009 | aj
Hi all, Is there any standard for percentage voiding on the center thermal pad on a QFN? We use the dot matrix array for paste to allow for outgassing etc, but we have had a couple of xray inspection "fails" for voiding on this pad , in or around 3
