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Subject: Re: [Homebrew_PCBs] Soldering 16-pin LFCSP?

From: Adam Seychell <a_seychell@...>
Date: 2005-02-02

tkreyche wrote:
>
> I'm hand soldering 28-pin SSOP's and similar no problem using solder
> paste and a heat gun.
>
> Now I've run into an IC I want to use that's in a 16-pin LFCSP !?!
>
> Is this even possible with the same technique or should I just find
> another IC? It looks difficult if not damn near impossible.
>
> thanks, Tom
>


Here is an article on the topic of your question;
http://www.edn.com/contents/images/447009.pdf

I assume the package your soldering is 3x3mm LFCSP.
http://www.analog.com/UploadedFiles/Packages/52467337CP16_1.pdf

I've never tried soldering anything that didn't have pins coming out of
the side. Pins with 0.5mm pitch is not impossible with careful control
of all your PCB process methods. I think your only chance is with an
adjustable hot air gun. You may need to modify your hot air gun to allow
a small stream of hot air. Its unfortunate the fan speeds on
conventional hot air guns do not allow flow rate to be adjusted low
enough for SMD rework. These guns have a AC/DC universal motor (like a
hair dryer), so a simple resistor in series with the motor will slow it
down.
The only problem I see is that if you don't have solder mask, then the
self centering action due to surface tension of wet solder may not go as
planned.