Electronics Forum | Mon May 28 17:43:33 EDT 2001 | davef
Does this device have a integral heat sink / metal slug on top, like a TI TM320C6XXX er a Altera EP20K4XX? Compare the size of the pads on the interposer and the board. Compare the type solder mask [NSMD vs SMD] on the interposer and the board. Wh
Electronics Forum | Thu Jan 27 14:16:14 EST 2000 | Tuan Bui
I've tried Indium NC-SMQ92(96.5Sn 3.5Ag) on these MCMs and achieved only marginal wetting on pads and parts. The good wetting is what I try to achieve, shiny is what my engineers want (Prototype environment). Does pre-cleaning the PWBs in ultrasonic
Electronics Forum | Mon Jan 03 14:00:06 EST 2000 | John Anderson
Has anyone had luck with 0201 cap board design, solder printing and reflow? IPC-SM-782 does not provide much help. I am particularly interested in attach pad design, stencil aperture design and thickness, solder paste (mesh, metal content, etc.), and
Electronics Forum | Fri Jun 25 09:43:24 EDT 1999 | Dave F
snip | | Dear John/Earl | | Thanks for your clarifications. To me also the problem does not seem to be linked with the PCB. The Pre heater temp. is set at | 450 degree C. We are using Alpha Aq. cleanable flux. Can you elaborate on the Desired
Electronics Forum | Fri Dec 18 00:49:43 EST 1998 | Mr Mariscal
I have been developing a BGA Process and are having problems with a 310 IO PBGA reflowing. I am achieving good wetting exept 2 to 5 balls on the outer perimeter I have a good profile my air flow is set per mfg spec, the strange thing is that it does
Electronics Forum | Fri Dec 18 00:48:35 EST 1998 | Mr Mariscal
I have developing a BGA Process and having problems with 310 IO PBGA reflowing. I am achieving good wetting exept 2 to 5 balls on the outer perimeter I have a good profile my air flow is set per mfg spec, the stange thing is that it does not happ
Electronics Forum | Mon Jul 20 17:40:48 EDT 1998 | socheat khun
| Does anyone know why this typically occurs. We have seen capacitors crack due to stressing. Any good solutions? | Regards, | | Steve. Hi steve! Did you check component date-code, reflow profile and component placement height. it has happen to me
Electronics Forum | Wed Nov 21 10:41:03 EST 2001 | arzu
Hello, Sometimes you have no choice other than putting uvias in ubga's-pads. I know examples of high-end mass production of products with ubgas having voids. (no problems, but always voids visable in x-ray) I also performed a DOE a while ago to avoid
Electronics Forum | Fri Sep 13 14:35:03 EDT 2002 | davef
Thanks Bernard. On your profile: Adding gold to your solder alloy will increase the liquious temperature. So slowing your reflow oven conveyor is a perfectly reasonable approach, especially for pads with low surface area. We don't even notice a di
Electronics Forum | Tue Oct 22 17:23:35 EDT 2002 | Yannick
Hi, I wondering if someone know the anwser to that. I'm using a solder paste 63/37 and on the solder joint we have a tiny little layer or flux who is like crystalin. I try to play with my profile the get it off but I don't get much success. So D
