Electronics Forum | Fri Dec 21 08:21:16 EST 2007 | mulder0990
Thank you for the responses. I am doing this to get a better understanding of the parts and packages at the plant I work at. We do not have a 'dummy' guide here and it seems that except for the test when you get hired in, for some positions you do
Electronics Forum | Fri Jan 04 09:44:59 EST 2008 | philkaz
Hello, I am Philip Kazmierowicz and I work with KIC, a Thermal Profiling company. We have done many lifetime experiments on Printed Circuit Boards over the years. The key thing to understand is that if the primary material of the board in FR4 fiber
Electronics Forum | Tue Jan 15 15:53:14 EST 2008 | jmelson
I only build my own products, so it has to meet my needs for QA only. I am doing some 20 mil lead pitch (0.5mm) and will soon be doing a 0.4 mm pitch part. I have more magnification on my microscopes (40X) but almost never need to go that high. If
Electronics Forum | Thu Feb 07 13:46:07 EST 2008 | slthomas
I would probably try to get my boss to spring for a digital anemometer (air velocity meter) and figure out what my velocity needed to be to get the specified airflow. Then just check it daily before production starts and when it starts to slow down,
Electronics Forum | Fri Feb 22 13:24:24 EST 2008 | mulder0990
How did I know senior was going to get in here too. Nice to see you again. I figured as much with the height difference, but I do not have the equipment here to test my thoughts. We somehow have our machine dialed in to run the 0201 parts with W
Electronics Forum | Mon Feb 25 08:14:04 EST 2008 | adetuc
Hi ... We use DRS24C Air-Vac machines for placing BGA devices, and have been having problems with shorts on corners of one device in particular, its a PBGA and its size is 4.5cm square and 15grams weight. When the component is picked up and the com
Electronics Forum | Thu Mar 13 16:37:48 EDT 2008 | darburch
The only time the customer is going to care about the standards is when it costs them money. Unsophisticated customers will continue the practice of providing little or no useful information, poorly designed boards and ridiculous mods until there is
Electronics Forum | Tue Apr 22 03:46:19 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 | Mon Apr 14 16:21:58 EDT 2008 | ck_the_flip
Bottom-side SMT parts CAN and DO go liquidus during the 2nd reflow cycle. It could be that there was enough variability between the 2 different lot code PCBs to cause the parts to fall off. Remember wetting force determines surface tension (the abi
Electronics Forum | Wed Apr 16 11:29:31 EDT 2008 | mmjm_1099
Per Tony SMT Here are more photos: Q15, Q16, Q17 represent good transistors on a 1 up board with the transistor locations that are in question. Q13 is a good transistor on a bad 2up board. Right next to it is Q14 a bad transistor on a bad 2 up boa