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<DIV>Eric,</DIV>
<DIV> </DIV>
<DIV>Here is a start: (2 cents from someone who is pretty new to surface mount
stuff)</DIV>
<DIV> </DIV>
<DIV>I found MLFs to be real tricky -- like my first attempt (hand
soldering) failed (4mm x 4mm 20 pin)</DIV>
<DIV>Assembly house did some for me as a favor by dotting solder paste and
baking in reflow oven.</DIV>
<DIV>Might have been able to do at home. (Some people have -- search
internet ).</DIV>
<DIV>I don't expect too many favors like the assembly house did for me so
I managed to redesign with SOIC and sleep better thinking about if I have to do
more protos -- I can do them myself.</DIV>
<DIV> </DIV>
<DIV>TQFP 0.8 mm lead pitch are easy with magnification or if you are Dale Wheat
without any magnification.</DIV>
<DIV>Some of the finer pitch TQFPs get pretty tricky. You have to start
worrying about lifting traces if you stay on a joint too long. Brian has
managed the 0.5 mm stuff. He might have some words.</DIV>
<DIV> </DIV>
<DIV>For resistors:</DIV>
<DIV>I thought 0805s were tough until I got a good pair of tweezers now even
0603s are reasonable.</DIV>
<DIV>Have not ventured further down in scale -- of course mind your power
dissipation ratings as you get smaller.</DIV>
<DIV> </DIV>
<DIV>If you are not pressed for space 1206 resistors are real friendly.</DIV>
<DIV> </DIV>
<DIV>Watch Dale or someone skilled doing SMD asm. You will learn a lot in a
short time.</DIV>
<DIV>Also scan the web for tutorial videos. Utube, SparkFun....</DIV>
<DIV> </DIV>
<DIV>Having the right solder is important too. </DIV>
<DIV> </DIV>
<DIV>I have .015" dia 62/36/2 solder from Radio Shack that i really
like for doing tiny stuff.</DIV>
<DIV>I think that is the Tin/Lead/Silver ratio.</DIV>
<DIV> </DIV>
<DIV>If you discover that you are really good and solder the devices that are
the size of dust particles -- always keep in mind what it will take to make some
changes to your design if you don't have the cash to run lots of proto revs on
PC boards. </DIV>
<DIV> </DIV>
<DIV>Ron</DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV> </DIV>
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