Electronics Forum | Wed Dec 20 04:43:36 EST 2006 | greg york
Any decent flux would volatise off with the heat of the wave unless absorbed into the solder mask. Test this by trying to clean in alcohol or common solvent aerosol, if it does not clean then it is probably Mineral Salts from solder mask fillers. Ano
Electronics Forum | Wed Dec 27 08:11:46 EST 2006 | billyd
Thanks dude. It's a bit tough, but I guess so long as it's well thought out, it's like anything else. I shoot for a 60% coverage, pre reflow, with the vias either filled with epoxy, or capped with mask, at least if the plan is to use the thermal pad
Electronics Forum | Wed Jan 03 10:41:47 EST 2007 | Rob
Consider this: The inner balls will be at a lower temperture than the outer balls in reflow, so if you cannot inpsect them then that may be where your problem lies. Are you reworking with a specialist machine that is directing the right amount of h
Electronics Forum | Tue Jan 16 01:22:35 EST 2007 | samsim
Hi Stephen, Q2) As per my understanding, no solder paste supplier or any organisation provide Mixing standard or ratio as it is not recommanded. However, I do know that some company, they allow mixing of old and new solder paste (as solder paste is
Electronics Forum | Fri Jan 19 10:43:28 EST 2007 | jimmyjames
You guys are all joking right?! There aren't any contaminates in your solder, the different colors on the surface are completely normal and even expected. The top layer of solder oxidizes and the structure of the surface resembles crystals, refract
Electronics Forum | Mon Jan 29 14:10:19 EST 2007 | tonang
We use M/C printer Samsung SP400V with M/C setting : - Auto Cleaning time 15 ea - SQG down lenght (mm); Front 0.5 Rear 0.5 - SQG Presure Front 0.5 KG, Rear 0.5 Kg - Print speed Front 30 mm/sec, rear 30 mm/sec M/C reflow Heller 1707 EXL, with setting
Electronics Forum | Mon Feb 05 10:21:21 EST 2007 | davef
Thermal conductivity [W/m-�C] * Silver: 418 * Aluminum: 403 * Copper [rolled annealed]: 392 * Copper [electrodeposited]: 392 * Gold: 297 * Nickel: 90.7 * Tin: 73 * SAC: 73 * Castin: 57 * Pb37Sn63: 51 * Lead: 35 * Epoxy, phenolic: 25-75 * Conformal co
Electronics Forum | Tue Mar 06 19:45:52 EST 2007 | davef
DPAK align on the tab with leaded solders. They don't align much with unleaded solders, but we know that your Indium NC-SMQ 92J is leaded. So, there may be too much paste on the heat sink tab causing the component to float [or wim] during reflow. If
Electronics Forum | Mon Mar 12 11:53:52 EDT 2007 | realchunks
Hi Coop, Sounds like you are having top side wetting issues. Generally this is flux related, but with a foam fluxer, I'd kinda doubt it's the fluxer. Could be heat related as well. Try slowing the conveyor speed to verify. Long leads - hmmmmm.
Electronics Forum | Wed Mar 14 12:06:15 EDT 2007 | Oswaldo Rey
There is an approximate 1W dissipation and has a 2 sq in area below part on solder side as a heat sink, vias are to physically conect this solder side area to power pad, so its necessary to use an adequate amount of paste. I really don�t think it has
