Chip Maxim

[SD]

Hi all

For solder this chip, Maxim 1987, on to laptop Hp Compaq NC series,
is a square of 6 mm side, 12 pin side, think that you succeed with a
soldering iron with fine tip, or it could go one better hotgun?

The lead free? or not, must be many mm? and paste flux soldering?

Which approach do you recommend?

Thanks in advance

Regards

http://radek.chlip.com/files/nc/zdj/IMG_2216.jpg

http://obrazki.elektroda.net/0_1206512210.jpg

http://radek.chlip.com/files/nc/nc.html

[Smitty Two]

In article <4d89e9c2$0$18237$4faf...@reader2.news.tin.it>,
"SD" <gfegk@gfdsd> wrote:

> Hi all
>
> For solder this chip, Maxim 1987, on to laptop Hp Compaq NC series,
> is a square of 6 mm side, 12 pin side, think that you succeed with a
> soldering iron with fine tip, or it could go one better hotgun?
>
> The lead free? or not, must be many mm? and paste flux soldering?
>
>
> Which approach do you recommend?
>

Not lead free. Liquid flux. .015" solder. Fine tip soldering pencil.
800F.

I'll leave the conversions to your systems of measurement up to you.

I'll add this caveat: If you had to ask those questions, you may not be
qualified to make the repair.

[SD]

>>
>
> Not lead free. Liquid flux. .015" solder. Fine tip soldering pencil.
> 800F.
>
> I'll leave the conversions to your systems of measurement up to you.
>
> I'll add this caveat: If you had to ask those questions, you may not be
> qualified to make the repair.

Thanks

Recommend some soldering technique?

Regards

[Archon]

Plenty of help on Youtube :

http://www.youtube.com/watch?v=3NN7UGWYmBY

JC

[Archon]

I'd suggest trying your technique on scrap boards first, old hard drives
are a useful source.
JC

[Wild_Bill]

This same IC was asked about, here on SER, not long ago.. probably for the
same application, as there were lots of search results wrt flexing boards
making this IC's connections open.

The package of this IC is 40-pin? Thin QFN 6mmx6mm.. there are no leads on
this IC package, click image for a larger picture:

http://www.pchub.com/uph/laptop/507-29494-6753/Maxim-MAX1987-ETM-Power-IC.html

Hot air reflow would be a good approach, but tinning the IC pads and the
board pads with leaded solder, then placing/holding the IC in position,
should allow someone who's fairly well skilled at soldering to reflow the
connections with a low-to-medium heat soldering iron equipped with a fine
tip.

Trying to apply/add solder to the individual pads with the IC in place could
easily cause shorts/bridges between the contacts, which could require
removal of the IC to remove the excess solder.

If the board pads have enough lead solder applied to them, just applying
some liquid flux, then positioning the IC and touching the contacts with a
fine tip of a soldering iron would likely be a reasonable method of
reflowing the connections.

For small components and/or fine pitch ICs, I avoid adding solder with the
part in position since it's too easy to apply too much solder.. instead, I
try to make sure that the board contacts have enough solder, and after
applying liquid flux, it's easier to just reflow the contacts.

--
Cheers,
WB
.............

"SD" <gfegk@gfdsd> wrote in message
news:4d89e9c2$0$18237$4faf...@reader2.news.tin.it...

[SD]

The bga solder balls? can be solder with solder iron?

Recommend me some type of solder balls for this chip Maxim.

Thanks

Regards

[Wild_Bill]

My guess is that the board manufacturer uses paste to hold the IC in place,
then heats the board.
Search "QFN stencil" and "QFN soldering".

http://www.solder.net/stencilmate.asp

http://blog.screamingcircuits.com/2006/10/more_qfn_dfm.html

http://store.curiousinventor.com/guides/Surface_Mount_Soldering/QFN/

http://hackaday.com/2010/05/04/qfn-or-mlf-soldering-without-solder-paste/

No balls should be needed.. the IC is not BGA, it's QFN.

Hot air would most likely be ideal, but a soldering iron and skill could
suffice. This type of repair is best accomplished by someone with skill and
experience in SMT repairs.

This is why I recommend liquid flux if enough solder is already in place..
then just touch the contacts and pads, moving around the IC (without trying
to add solder).

If the IC has been removed, I would apply a minimal amount of lead solder to
the board pads, then with the IC in position (and liquid flux applied),
carefully heat the contacts and pads.

--
Cheers,
WB
.............

"SD" <gfegk@gfdsd> wrote in message

news:4d8a51d7$0$38645$4faf...@reader1.news.tin.it...

[Ken]

Where did you buy the chip you are trying to install?? I have a board
that needs the chip replaced, and I might try it if I could get a chip.

[Smitty Two]

In article <Gpyip.779589$pX3.1...@en-nntp-11.dc1.easynews.com>,
"Wild_Bill" <wb_wi...@XSPAMyahoo.com> wrote:

>
> If the IC has been removed, I would apply a minimal amount of lead solder to
> the board pads, then with the IC in position (and liquid flux applied),
> carefully heat the contacts and pads.
>

I think it's counterproductive to apply solder first, which would serve
to keep the chip off the board. I absolutely agree with the liquid flux
idea, then a drop of solder on the iron and skate it down each edge.

[SD]

>
> Where did you buy the chip you are trying to install?? I have a board
> that needs the chip replaced, and I might try it if I could get a chip.

http://cgi.ebay.it/ws/eBayISAPI.dll?ViewItem&item=360351163467&ssPageName=STRK:MESINDXX:IT

maybe this chip is not the same as that of my laptop
I do not know if my laptop or yours could be OK.

Another question.
The difference between this
http://cgi.ebay.it/ws/eBayISAPI.dll?ViewItem&item=110658426046&ssPageName=STRK:MESINDXX:IT
and this,
http://cgi.ebay.it/ws/eBayISAPI.dll?ViewItem&item=380296779947&ssPageName=STRK:MESINDXX:IT

what is?

Thanks

Regards