Electronics Forum | Tue Apr 15 03:16:14 EDT 2008 | janz
Hello, We are having a problem with soldering QFP100 (16mmx16mmx1mm). Board dimensions: 70mmx50mmx1.8. FR4 two layers � single SMT assembly. Finish: HASL-lead free Oven: 7 zones �hot air Paste: lead free We have noticed that two groups of legs
Electronics Forum | Wed Apr 23 21:34:24 EDT 2008 | fowlerchang
It is CSP reliability issue, which is the mobile CPU from Spreadtrum. All the tests passed and shipped to customer. They assembly them and tested but failed. After they reflow this CSP with hot air gun, some of the boards passed. We got some board
Electronics Forum | Thu May 01 16:27:04 EDT 2008 | chrisawallace
As Mark stated in a different reply, we also send our Pb-free BGA's out to be re-balled with SnPb paste so that we don't have to elevate the reflow temperatures. You have to be careful regarding the individual components on your boards as although m
Electronics Forum | Fri May 02 08:44:36 EDT 2008 | realchunks
Sure you can. But I don't have the time, money or resourses to do this. I do not have the luxery of only getting SnPb parts. Wish I did, but I don't. As for temp specs, I know the specs on all my parts. We profile our ovens every month. We can
Electronics Forum | Fri May 23 23:47:46 EDT 2008 | dint46
Wayne; Several things. 1.check the vendors and see what black oxide they are using are they the same ? It might be that. 2.You should bake your pcbs before the thermal stress is applied. To remove moisture. At your shop. The proce
Electronics Forum | Wed May 28 08:46:39 EDT 2008 | ck_the_flip
I've talked to several Applications Engineers and Chemists from a couple of different paste manufacturers and they confirm that the profiles on their data sheets are nothing but guidelines. It's up to you, Process Engineer or Process Tech, to develo
Electronics Forum | Fri Jul 11 18:35:53 EDT 2008 | ratsalad
Ms. Chunks, I am an industrial engineering student at the University of Wisconsin - Milwaukee in Milwaukee, WI USA with many years of experience in the SMT assembly industry. By your description, an IE job with your company offers just the typ
Electronics Forum | Fri Jul 11 11:14:30 EDT 2008 | bkreiman
I agree that it should be a non-issue considering that the primary purpose of a solder joint is to electrically connect the lead to the board. However, there are some here that think these leads should be touched up because this part is a power jack
Electronics Forum | Wed Jul 30 07:22:17 EDT 2008 | davef
Not sure what software you have, but somehow you must be accumulating costs by process and you probably know [or can figure-out] how many boards you processed. From this, you can calculate a standard cost of a process. Continuing, there is a thread,
Electronics Forum | Thu Aug 07 11:58:36 EDT 2008 | pbarton
We have experienced the same problem with Pd/AG and P/Ag terminations on precision resistive parts. The problem is dissolution of the termination metallisation into the bulk solder. This is exacerbated by the higher thermal profiles required for RoHS
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