Cheap way of mounting a BGA chip
vorange
I tried to inquire about this with a board manufacturer. I told them
I'd like to get a couple of 200+ pin bga chips mounted onto a board
and I got back a quote for a few hundred dollars!!
Now how in the hell can any hobbyists prototype anything if just
mounting a chip costs a few hundred dollars.
I know there are BGA adapters out there but I don't want to go that
route.
Any suggestions or does anyone know any low cost (e.g. 50 dollars)
shop which will mount a BGA on a board if supplied with the chip &
board.
Thanks
Didi
See this old posting of mine here:
http://groups.google.com/group/comp.arch.embedded/msg/ec6a54278a352d51?dmode=source
donald
> On Aug 24, 10:57 pm, vorange <orange...@yahoo.com> wrote:
>> Anyone know of any low cost way of mounting a BGA chip?
>>
>> I tried to inquire about this with a board manufacturer. I told them
>> I'd like to get a couple of 200+ pin bga chips mounted onto a board
>> and I got back a quote for a few hundred dollars!!
>>
>> Now how in the hell can any hobbyists prototype anything if just
>> mounting a chip costs a few hundred dollars.
Now how in the hell are these companies going to make any money if they
have to hold hands with every beginner that comes along.
You what to play, you have to pay. ( or get out of the business )
donald
Nils
>>> Now how in the hell can any hobbyists prototype anything if just
>>> mounting a chip costs a few hundred dollars.
>
> Now how in the hell are these companies going to make any money if they
> have to hold hands with every beginner that comes along.
>
>
> You what to play, you have to pay. ( or get out of the business )
Todays hobbyists are tomorrows customers. :-)
vorange
>
> - Show quoted text -
I've never done it before but is it possible to make a board where the
edge pins of the BGA have a through-hole via to the other side of the
board. I can then mount the chip by tacking the 4 corners through the
via from the other side of the board. And then put the whole board in
the oven to bake.
Is this practical at all? The bga pins already have solder on them do
they not?
Didi
So why do you direct your reply at me - was it so hard to
read before replying. I posted the solution, you see,
not the question.
Didi
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donald
> On Aug 25, 12:38 am, donald <don...@notinmyinbox.com> wrote:
>> Didi wrote:
>>> On Aug 24, 10:57 pm, vorange <orange...@yahoo.com> wrote:
>>>> Anyone know of any low cost way of mounting a BGA chip?
>>>> I tried to inquire about this with a board manufacturer. I told them
>>>> I'd like to get a couple of 200+ pin bga chips mounted onto a board
>>>> and I got back a quote for a few hundred dollars!!
>>>> Now how in the hell can any hobbyists prototype anything if just
>>>> mounting a chip costs a few hundred dollars.
>> Now how in the hell are these companies going to make any money if they
>> have to hold hands with every beginner that comes along.
>>
>> You what to play, you have to pay. ( or get out of the business )
>>
>> donald
>
> So why do you direct your reply at me - was it so hard to
> read before replying. I posted the solution, you see,
> not the question.
>
> Didi
Sorry
Jerry McBride
If you have control over the manufacture of the board, the answer is yes.
I've done just that on one-off samples for low budget in-house projects.
--
Jerry McBride (jmcb...@mail-on.us)
vorange
> > I've never done it before but is it possible to make a board where the
> > edge pins of the BGA have a through-hole via to the other side of the
> > board. I can then mount the chip by tacking the 4 corners through the
> > via from the other side of the board. And then put the whole board in
> > the oven to bake.
>
> > Is this practical at all? The bga pins already have solder on them do
> > they not?
>
> If you have control over the manufacture of the board, the answer is yes.
> I've done just that on one-off samples for low budget in-house projects.
Thanks for the reply.
Is there anything beyond what I described that I should be doing to
make sure the chip adheres? Should I perhaps be applying a small
amount of (paste) flux to the underside of the chip so the solder
melts at a lower temperature or is that unnecessary.
Didi
> On Aug 24, 5:29 pm, Didi <d...@tgi-sci.com> wrote:
>
> I've never done it before but is it possible to make a board where the
> edge pins of the BGA have a through-hole via to the other side of the
> board. I can then mount the chip by tacking the 4 corners through the
> via from the other side of the board. And then put the whole board in
> the oven to bake.
>
> Is this practical at all? The bga pins already have solder on them do
> they not?
The BGA balls are all solder, actually.
You have to stick the BGA with some flux - not liquid but
not too hard either, I use a German one called "loethonig"
(soldering honey... :-). Once stuck at its position, just
reflow the board as I descrbed in my older posts and you are
done (apart from washing). During reflow, the BGA floats
on its liquid balls and gets properly positioned by
surface tension. Be careful to stick it at the right place,
it can be offset by a row... (once happened to me).
Didi
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Original message: http://groups.google.com/group/comp.arch.embedded/msg/cce67e22240dbd19?dmode=source
John Devereux
Hi Didi,
I did not understand what you meant about reflowing the BGA with belly
up - could you explain again? Do you mean reflow the chips themselves
(alone)?
--
John Devereux
Didi
> ....
> Hi Didi,
>
> I did not understand what you meant about reflowing the BGA with belly
> up - could you explain again? Do you mean reflow the chips themselves
> (alone)?
Hi John,
yes, that's it - just the BGA alone. The reason is that some balls - I
have
had up to 2-3 per BGA - are "coldly" soldered to the BGA itself; so
when the
ball gets liquid and there is a hole underneath, it just flows throuh
and the BGA
pad gets completely disconnected. I don't know if all BGAs do it, but
I have
seen the effect on my first board with all 3 different sourced BGAs.
Ever since I fry them once with flux belly up and have no issues, it
does not
take a lot to avoid cold soldering joints after all.
Didi
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Original message: http://groups.google.com/group/comp.arch.embedded/msg/ab78e8464cb13486?dmode=source
John Devereux
> John Devereux wrote:
>> ....
>> Hi Didi,
>>
>> I did not understand what you meant about reflowing the BGA with belly
>> up - could you explain again? Do you mean reflow the chips themselves
>> (alone)?
>
> Hi John,
>
> yes, that's it - just the BGA alone. The reason is that some balls - I
> have
> had up to 2-3 per BGA - are "coldly" soldered to the BGA itself; so
> when the
> ball gets liquid and there is a hole underneath, it just flows throuh
> and the BGA
> pad gets completely disconnected. I don't know if all BGAs do it, but
> I have
> seen the effect on my first board with all 3 different sourced BGAs.
> Ever since I fry them once with flux belly up and have no issues, it
> does not
> take a lot to avoid cold soldering joints after all.
Interesting, thanks!
--
John Devereux
vorange
> yes, that's it - just the BGA alone. The reason is that some balls - I
Just to get your opinion, what do you think of my method of tacking
the 4 corners of the
BGA with 4 through-hole vias and then putting it in the oven to bake
(perhaps with a small lead weight positioned directly over the chip to
force it down and keep it from sliding).
Do all BGA chips come with balls with solder already on them or just
some?
Didi
> On Aug 25, 9:26 am, Didi <d...@tgi-sci.com> wrote:
>
> > yes, that's it - just the BGA alone. The reason is that some balls - I
>
> Just to get your opinion, what do you think of my method of tacking
> the 4 corners of the
> BGA with 4 through-hole vias and then putting it in the oven to bake
> (perhaps with a small lead weight positioned directly over the chip to
> force it down and keep it from sliding).
>
I have not tried this but it does not sound like something which would
have much of a chance to work.
The first time I tried to solder the 3 BGAs on my first BGA board
many years ago I stuck them in place with a UV hardening glue, just
a drop every other corner or so. This fixed them well in place which
was
cute, but they did not have the chance to float and drop somewhat over
the reflown balls so this was a complete failure. Expect something
like that... :-).
They do not slide so easily, just make sure to position the BGA
in the right place (measuring from two board edges should be enough).
Be very careful when you take the setup out of the oven; everything
is liquid and if you knock it in some obstacle you are gone - *that*
is
when parts will slide (have had this as well, of course). If this
happens, all you can do is to start all over after cleaning up the
mess and reballing the BGA(s)...
> Do all BGA chips come with balls with solder already on them or just
> some?
They all come with balls *of* solder, not with. The entire balls are
made of solder.
Do not even think to put lead on top of the BGA, even if it does not
melt to mess up the entire board the balls can take little more
weight than the BGA itself while liquid.
Leon
A large proportion of that is the cost of the stencil. Then there is
the X-ray cost.
Leon
Didi
> On 24 Aug, 20:57, vorange <orange...@yahoo.com> wrote:
>
> > Anyone know of any low cost way of mounting a BGA chip?
>
>
> A large proportion of that is the cost of the stencil. Then there is
> the X-ray cost.
Such nonsense.
What is he supposed to do with the stencil on a *BGA*?
And what XRAY on Earth do you suggest for a prototype
the guy wants to make?
I have been doing BGAs for almost 10 years now and when
I have used a stencil it has been for the parts other
than the BGAs; I have never used XRAY.
Didi
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Original message: http://groups.google.com/group/comp.arch.embedded/msg/081a27f5baa07802?dmode=source
mng
Gunther Mannigel
> Anyone know of any low cost way of mounting a BGA chip?
http://www.lrr.in.tum.de/~acher/bga/index.html
Send it through babelfish.
cheers
Gunther
Leon
Stencils are often used with BGAs for applying flux and solder paste.
Leon
Didi
I know they can be used. They are unnecessary, though.
Flux is enough to solder a BGA and applying it through
a stencil is like precision positioning of the chips
you are going to put in the fryer.
Didi