Electronics Forum | Thu Oct 28 13:36:14 EDT 1999 | Bart Smith
I am a design engineer and have a circuit board design with a 292 pin BGA on it. The board manufacturer is experiencing a failure rate of about 2.8% on the BGA device due to soldering problems. This is my first experience with BGA. How does the 2.
Electronics Forum | Fri Oct 29 05:23:00 EDT 1999 | Wolfgang Busko
Hi Bart, that�s much to high. If that would happen to me my boss would tear my head off. For improving the yields you must find the cause for the soldering problems. What are the symptoms? What could be the cause for the symptoms? Could be design pr
Electronics Forum | Sat Feb 05 09:01:15 EST 2000 | Dave F
JS: The issue is not how efficiently/effectively that you can run your placement machine, probably. The issue is how efficiently you can run that part of your assembly process that is the bottleneck. Other than improving quality, optimizing any pa
Electronics Forum | Wed Feb 17 13:02:03 EST 2016 | comatose
The layer count itself isn't going to be what drives yields. What is the trace/space? How much annular ring for vias did you give them to play with? Class 2 or class 3? What's the worst hole aspect ratio? Controlled impedance? The closer you run to y
Electronics Forum | Fri Jun 07 14:05:39 EDT 2024 | davidk
I wanted to open a discussion and ask about opinion: What is a normal result of the inspection of an AOI? How many falls calls per component /opportunity is bad/normal/good? How many defects per component/opportunity is bad/normal/good? What is goo
Electronics Forum | Thu Jun 13 14:41:40 EDT 2024 | tommy_magyar
Hi David, In one of my previous jobs I worked as an AOI/AXI process engineer and we had a set target of 75% FPY. This means that 75% of the boards at IPC Class 3 standards would not have a single false call. This also means you would need to set y
Electronics Forum | Tue Jun 29 11:46:36 EDT 2010 | davef
Prins: Everyone has equations. Here's one some people use: False call rate = [Number of defective boards, but good at inspection]/[Total number of boards produced] Why don't you ask the people [that calculated the numbers that confuse you] how the
Electronics Forum | Thu Oct 11 06:36:57 EDT 2007 | cyber_wolf
Feeder is brand new. (Checked cal. even though it was new) Lighting is good. Machine is in perfect cal. Nozzles are brand spankin new from Fuji. I was able to lower the reject rate considerably by playing with the offset and gain. I am placing caps
Electronics Forum | Wed Oct 10 11:20:31 EDT 2007 | jdengler
Do all 0201's reject at the same rate? If even 1 P/N has a lower reject rate this can point towards a feeder problem. I have had a similar problem on a CP-IV-2 with 0402's that was caused by feeders. If all reject at the same rate it can be the PD o
Electronics Forum | Thu Nov 10 23:43:33 EST 2022 | sarason
Are you using the correct nozzle for 0402? Cant remember the number OTTOMH but 501 rings a bell. somewhere I have the table, it is in the Juki service manual IIRC. This would explain placing all others okay but 0402 is not very good , Senoirtech is c
