Electronics Forum | Thu Feb 21 13:08:06 EST 2002 | vincent_f
Hello, I had recently a problem of crack between the solder ball (SnPb) and the Ni layer of the PCB pad. We use Electroless Ni/Au technology for PCB. This phenomena is amazing because the crack is very clean (straight) and it creates a space betwee
Electronics Forum | Sun Feb 24 02:21:39 EST 2002 | CJ
I work in a test-support role supporting a bluetooth production line. We use HP spectrum analysers in our final test solution and the solution to a lot of our fails is solved by calibrating these analysers. Normally we do both a Freq/Amplitude calibr
Electronics Forum | Mon Feb 25 07:59:47 EST 2002 | Jim Mills
Customer has requested a custom CBGA pakaged resistor network.I've seen a lot of info about TCE mismatch but aslo have heard that using 0.025-0.030 balls offers some stress releif which allows for the TCE mismatch to become less of a problem. Would
Electronics Forum | Mon Feb 25 15:09:06 EST 2002 | jax
Kelvin, You can find the Standard acceptable levels and testing procedures from IPC. Here's a little advice from the fellas' over at PCFAB: As a guideline, we recommend that for assemblies processed with low-solids flux technology and that are not cl
Electronics Forum | Wed Feb 27 10:35:25 EST 2002 | dougt
This is just a general question. I'm no vacuum expert and I'm curious how pick and place equipment manufacturers are able to turn off and purge their vacuum systems and sense this so fast when they are placing a part on a board. Are they turning it
Electronics Forum | Wed Feb 27 19:55:13 EST 2002 | nifhail
Hi, I need help to understand further on the via in pad for 0402 requirement. If I were to do the DFM over the brd design which consist of 0402 with via on pad, what is the criteria that I should look for ? I learned that the via in pad does not wor
Electronics Forum | Fri Mar 01 04:42:13 EST 2002 | wbu
Hi Nightbull, here�s daybull speaking. Yes the same question for me, what kind of auditor was that ? What I do in an similar audit situation is simply pointing to, if existing, an obvious lack of performance in certain processes depending on my humb
Electronics Forum | Sat Mar 09 07:09:44 EST 2002 | davef
Interesting findings. I agree that probably no one does �100% volume measurement and subgrouped Xbar and S charts�. Who would want to spend the money? Isn�t the issue making things, rather than measuring things? The microscope is used to make m
Electronics Forum | Tue Mar 12 11:20:08 EST 2002 | BTaylor
I agree with davef on most subjects including this one , we have used a microscope and an experienced inspector for years and done just fine. Recently due to customer demands we an acquired an ASC 3-D inspection station, and it works great it told us
Electronics Forum | Fri Mar 15 16:06:30 EST 2002 | shan
80??? Whatever leads to you to that assumption? I'd love to see a study stating that. Based on experimental results at our facility, overvolume due to the screener parameters have rarely caused a solder short. so, in conclusion, does one need a solde
