Electronics Forum | Wed Jan 19 00:42:09 EST 2000 | park kyung sam
In my case, when i solderd the bga in normal reflow(convection hot air). There is a lot of boid. i had tried to reduce void long time. so i reduced just a little. It did't satisfied me but now i cannot looking for the void in soldered bga i
Electronics Forum | Thu Jan 20 02:36:29 EST 2000 | erico
Hi wolfgang,Dave & PC: What I facing are: 1. The component lie flat on the board but only one side can get solder.The pad is ok, problem is with the chip. 2.I desolder the chip and go to view it under microscope and found that there is a line near t
Electronics Forum | Fri Jan 21 10:40:15 EST 2000 | Dave Chapman
Having adjusted the profile speed slower and adjusting the temps to the recommended lower levels, amazingly the mid chips have almost disapeared (90%). It appears they have been trying to run a "1 profile fits all" on the ovens for Alpha 737 and UP78
Electronics Forum | Sun Jan 23 03:23:09 EST 2000 | Rob Steltman
Hi We use a U-channel piece of high temperature silicon which is just pushed over the gold tabs before the soldering process. The silicon can be used over and over again. The advantages are that there is no mask on the board during the SMT process a
Electronics Forum | Fri Jan 14 09:17:08 EST 2000 | Wolfgang Busko
You need to have the right cutter for that and the necessary skill too. "Erem" a company from switzerland does have a very good cutter for that. I�ve seen cutting done with high speed miniflex ( those dentists tools ) too. Desoldering with a minitip-
Electronics Forum | Tue Jan 04 19:55:46 EST 2000 | Rob Thomas
Hello Yosef, non woven aramid reinforced pcb's are used where is a need for low CFT (coefficient of thermal expansion). Traditionally aramid pcb's were used in military applications in order to reduce the stress/failure rate of solder joints during
Electronics Forum | Tue Dec 28 12:34:03 EST 1999 | Justin Medernach
Jim, I wouldn't sweat a TCE mismatch between Ceramic chip components and FR4. No need to worry. 99.5% of consumer product out there utilizes this exact technology with no threat of failure due to CTE mismatch. The terminices of the components occu
Electronics Forum | Tue Dec 28 09:36:34 EST 1999 | Dan Woodward
Certainly automatic placement, preferably with vision system assistance will yield a more repeatable process. Process repeatability (paste deposition, connector placement, reflow cycle, etc.) will be your key to success here. Another possibility yo
Electronics Forum | Tue Dec 21 19:48:27 EST 1999 | Russ
John, we have waved 0603 packages for a long time, We have also started on 0402. Are you concerned with shorting across the component body or to other components? You should have no problems with these parts in a wave process. A couple of things
Electronics Forum | Tue Dec 21 19:57:45 EST 1999 | Russ
All of the information so far has been great, I would like to add one more thing to the puzzle. We have utilized a "homeplate" aperture on the stencil when the pad geometry or PCB design prohibits all of the above mentioned remedies. The hompeplat
