Electronics Forum | Tue Nov 27 01:43:29 EST 2001 | Anders
The reason why we are using soldered PCB jumpers is that it is cheaper than dip-switches, 0 ohms resistors, etc. Field updating is also easier. We are producing different variants of some of our products. It would nice if we could presolder the PCB
Electronics Forum | Tue Nov 27 15:57:58 EST 2001 | mparker
rather than applying jumpers, try thinking it another way. Have all possible jumper connections pre-made by the fab design. Use an exacto or dremel to "open" the undesired paths by removing a bit of copper trace. total flexibility, only one fab make
Electronics Forum | Tue Jan 08 17:29:20 EST 2002 | davef
Your research is on track. NC flux needs to reach activation temperature. Also, do not depend on the corrosion characteristics associated with the flux classification (ie, L1, L0, M1, M0, etc.), until the flux is activated by exposure to soldering
Electronics Forum | Thu Mar 14 09:21:38 EST 2002 | davef
You should be looking for a better method of depaneling your boards. Listen. If you breaking components, it's not the component. It's you. Either you are: * Applying too much force. * Bending the board too much. * Locating the components too clos
Electronics Forum | Tue Apr 02 11:21:46 EST 2002 | BTaylor
davef I assume this question is for my reply and me. We used a dexter\hysol underfill and a Camalot 5700 to dispense.Single line technique next to a small IC with 14 bumps around the perimeter.The conformal coating was applied with a small brush aro
Electronics Forum | Mon May 06 00:09:00 EDT 2002 | ianchan
as a followup thought, what is your current peak reflow deg-C? and reflow timing (sec)? Au/Ni calls for reflow temperature of 217 deg-C for solder fusion that produces secondary eutectic alloy. there was one time we thought 183 deg-C was the magic
Electronics Forum | Thu May 09 18:06:42 EDT 2002 | bcceng
janchan, don't know how many LGA's/LCC/BCC's you are placing but a short term solution that I can recommend is the application of solder bumps to the component and than place it after board has gone through reflow or even at the same time. Our compa
Electronics Forum | Fri May 31 09:09:21 EDT 2002 | russ
Dave, you would be correct in this application. I wish I could prevent these products from coming into our shop, but... I do like the idea of press fit and I will have to research on the availability and persuade the customers to change. I was wond
Electronics Forum | Wed Jun 19 22:03:23 EDT 2002 | davef
If you can assemble flawless products with these boards, do not be concerned about post-assembly quality issues. There is no current related specification in the US. Although, there may be some old military specifications that apply, but you would
Electronics Forum | Mon Aug 12 12:58:16 EDT 2002 | pjc
What I've done w/ eutectic ball BGA devices is after removing the BGA from the PCB, solder-suck the lands- get em nice a flat, apply a thin coat of gel flux to the solder lands and then a thin coat to only the bottom of the solder balls on the new BG
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