Daan,
Stack two defect marking arrows under each corner (should equal
0.020" standoff). Remove them after reflow.
Thanks
Ryan Grant
Advanced Technology Engineer
MCMS
(208) 898-1145
[log in to unmask]
> -----Original Message-----
> From: d. terstegge [SMTP:[log in to unmask]]
> Sent: Tuesday, October 10, 2000 8:25 AM
> To: [log in to unmask]
> Subject: Re: [TN] Heavy BGA's, now it's fine-pitch !
>
> Hi Jim,
>
> Thanks for the suggestion. Any idea on how thick such a spacer should be,
> and how to apply it ? Like I mentioned, trial and error is no option for
> this project.
>
> Kind regards,
>
> Daan Terstegge
> SMT Centre
> Signaal Communications
> Unclassified mail
> Personal Website: http://www.smtinfo.net
>
> >>> "Marsico, James" <[log in to unmask]> 10/10 2:08 pm >>>
> How about using a temporary spacer under each corner?
>
> Jim M.
>
>
> -----Original Message-----
> From: d. terstegge [SMTP:[log in to unmask]]
> Sent: Tuesday, October 10, 2000 9:59 AM
> To: [log in to unmask]
> Subject: [TN] Heavy BGA's, now it's fine-pitch !
>
> Hi Technet,
>
> I need your advice on this one:
> Some time ago there was a discussion about soldering problems with
> partnumberTMS320C6201GJC200 of Texas Instruments. It's a 1.27 mm pich BGA
> with a heavy heat-slug on top. The weight of the heat-slug makes the
> solderballs collapse a little too much, resulting in solder bridges.
> Now I've got to assemble some boards with similar parts, but with
> a
> much smaller ballpitch of only 0.8 mm.
> No problem for the ordinary type BGA's, but with the heatsink I'm
> starting to feel uncomfortable. For the record: it's TI's part
> numberTMX320C6203GLS.
> I've got to build two boards, and all I've got is two components.
> No
> trial and error possible......
> If anyone of you have experience or thoughts about this, please
> let
> me know.
>
> Kind regards,
>
> Daan Terstegge
> SMT Centre
> Signaal Communications
> Unclassified mail
> Personal Website: http://www.smtinfo.net
>
>
>
>
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