[Discuss-gnuradio] me v. 0.5mm pitch TSSOP [SSRP]

[David Carr]

I soldered the LTC1746 ADC onto its board today.  It was my first time 
to solder a SMT IC and after practicing with (melting) other junkbox 
parts I managed to do a fairly good job I think.  A few joints look like 
they might have a little less solder than I'd like but I'll call it good 
for now.  On a related note, the LTC7146 daughter board is progressing 
along nicely.  The LTC1746 is on a TSSOP adapter board (with 
groundplane) called a schmartboard.  The adapter board is pretty cool 
with space on the board to add things like bypass caps and its overall 
layout is pretty intelligent ...especially for $5.  
[http://www.schmartboard.com/]  A homemade pcb will carry the analog 
input stage, power supply and conversion clock circuitry.  The schematic 
is finalized and the layout is almost finished as well.  Unfortunately, 
I'll be in the Cayman Islands for the next week and a half so I probably 
won't make a lot of progress in that period. [grin] 

For the curious:
I was initially pretty daunted by soldering a .5mm pitch component but 
it turns out that it can be done with the right tools.  I used a Edsyn 
Loner temperature controlled iron at 600F with a "mini-wave" tip.  I 
highly reccomend this style of tip.  The trick to making good joints 
instead of a single large joint is to use lots of flux and to not fully 
load the tip with solder.  Also make sure you have desoldering braid for 
the inevitable oopsie.  If want there's a video on the Pace website that 
shows the technique used on a QFP. 
http://www.paceusa.com/_ApplicationSubList.asp?ApplicationGroupID=11#
Its not quite as easy as it looks but with a little practice its very 
doable.

-David Carr