Electronics Forum | Sat Oct 06 05:33:47 EDT 2001 | spchua
I had recently encounter the "black and grey" pads problems for the BGA pad after the convection re-flow. The pads shows in in "black and grey" color and a litter solder in it, and it happen in ramdom, when applied heat and solder on the "black and g
Electronics Forum | Thu Nov 01 16:06:54 EST 2001 | Stefan Witte
I disagree on the dirty glass scale offset theory. If you have a dirt spot on the scale, every time the axis comes over the spot it misses counts. After a few movements it will not find the components in the feeder anymore, because the failure adds u
Electronics Forum | Mon Oct 29 14:52:58 EST 2001 | kjmcbi
We have made a number of step up adhesive stencils using a new material called Cirlex. This material demonstrates excellent release characteristics and is easly cleaned. Typically the glue printing is after the solder printing. The stencil is all las
Electronics Forum | Fri Nov 09 20:15:26 EST 2001 | caldon
I concur with Dave.....I have done this often with little fall out. After rework reflow we would x-ray just to ensure an acceptable joint structure. Just for curiosity sakes....are you removing a defective BGA and replacing with a good one? Site pre
Electronics Forum | Mon Nov 12 16:11:59 EST 2001 | davef
Listen. Reworking 0201 is too expensive. Here�s watt yado � * Cut the lil� suka between the pads on the board using side cutters. * Flick each piece from its pad, after melting the solder with a standard soldering iron. * Solder the terminations
Electronics Forum | Wed Nov 21 04:46:27 EST 2001 | emmanuel
Yes, i confirm you that the BGA i'm refering to are Motorola BGA. The fractures that appear after 500 thermal cycles (-45�C/+125�C) are located in the solder joint/pad connection. We have been asked if this fractures are due to BGA & PCB design or to
Electronics Forum | Tue Dec 11 16:28:17 EST 2001 | genny
Our co. is thinking of moving to smocks, but we aren't there yet. However, I can understand why we might want to. Have you ever seen the static buildup on a wool sweater or a polar fleece vest after rubbing against a chair all day in a cold dry pra
Electronics Forum | Mon Dec 31 08:11:23 EST 2001 | hany_khoga
Dear all : We are suffering a severe curvature in our boards when coming out of the wave solder m/c. An Engineer suggested to enter them again for a second pass in the m/c expecting board were thermally mistreated just after the W.S. Can this real
Electronics Forum | Sat Jan 26 08:44:39 EST 2002 | Bigballs
What would happen if a 2 volt solar cell was hooked through a diode into to a 3.6 volt nicad (3xAA)? would it charge it at all? just a bit but never fully? would battery deliver 3.6 volt after charging? If left long enough would it charge fully?
Electronics Forum | Tue Jan 29 13:06:40 EST 2002 | Sergio Vito - Alan Patrick - Cristiano Dick
Dear sirs, We are experiencing problems with lines of lead formed inside the solder joint. In others words, there is a problem with the formation of the solder joint, after analyses on a microscope we can see the lead grouped in some positions. This
