17 Oct
2012
17 Oct
'12
5:12 p.m.
Only way I know of to handle BGA is doing solder reflow. This can be done with solder
paste and a hotplate, Sparkfun's website has info. The only hitch is that you can only
check if the joint is good by powering it up. Otherwise you need access to an x-ray
machine.
Sent from my iPhone
On 2012-10-17, at 7:55 PM, Chuck Guzis <cclist at sydex.com> wrote:
On 10/17/2012 11:24 AM, David Riley wrote:
I suppose. I've had terrible luck with
bridging, but I never
really kept at it long enough to get much good at soldering
fine-pitch parts. My wife got me a pretty decent iron as a
birthday present recently, though (I picked a good one!), so
I may be doing a bit more in the not-too-distant future (more
so if my QBUS board ever gets off the ground, because I don't
really feel like paying for assembly).
Speaking for myself only, soldering TQFP isn't terribly difficult--I could almost
solder an 0.8 mm lead pitch QFP without my glasses. 0.5 mm for me requires a binocular
loupe and careful checking with an inspection microscope. But I've done a lot of it
and had zero casualties, much to my surprise.
What I find more of a problem are SMT transistors and other tiny multi-lead components.
It takes a fairly steady hand to get them just right. For two-leaded components, you can
just let the component find its own place floating on two molten solder pads.
Hey, if I can do it, anyone can. I started with a 100W American Beauty iron wiring
point-to-point (lesson to be learned: Look before you grab). PCB was a learning
experience and SMT yet another one. I still don't know the right way to handle BGA
packages doing manual assembly, so I steer clear of those.
FWIW, I've got a motherboard here (386 or 486--I don't remember) where a QFP CPU
is mounted on a carrier that plugs into a PGA socket. The thing was purchased in that
configuration.
--Chuck