AVR-Chat

Last time I stuck down SMT parts I used flux (flux is your friend) on 
the pads first, put a tiny bit of solder on them flux 'em again (a 
flux pen is good).

Then tacked down the corners of the chip after making ABSOLUTELY SURE 
it was lined up properly (because you're not pulling it back off if 
you screw up).  Check it MANY TIMES to make sure it's turned/aligned 
properly.

Then solder down the rest of the pins.  Clean up any excess solder 
with a desoldering braid.  Last thing to do is to check each 
connection.  Actually this is a lot easier than you'd think.  Just 
run a pin from your meter over the pins slowly.  As it slips over the 
pin it will make a noise.  Loose pins make a dull sound you'll 
recognize right away.

Hope that helps a bit...might want to check into SMT soldering 
guides.  There are many available but I'm too lazy to check



--- In AVR-Chat@yahoogroups.com, "nangkon" <nangkon@y...> wrote:
> Hi there,
> 
> I wonder if solder paste is easier for soldering
> atmega128 on a board. I tried solder wire and
> the result is not too good and bridges formed
> frequently. It could be that I am using wire
> that is too thick. And my inexperience on soldering
> SMT parts definitely did not help at all. :)
> 
> If solder paste will do wonders, any recommended
> brand. I can use just regular iron with it, right?
> No hot air blower required?
> 
> thanks
> thomas