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Topic: What is the most challanging device that you have successfully soldered? (Read 1 time) previous topic - next topic

JoeN

Just wondering what my fellow hobbyists have done / can do with hobby type equipment. I started out with all-DIP type circuits like I think everyone has and just recently have started progressing into mostly surface-mount stuff. Wow, now the boards I make look professional, though oddly they are purple.  I've been having a mostly easy time soldering TQFP 0.5mm packages up to 144 pins and I assume I can do the larger packages if necessary, though I don't own any of them. Haven't does 0.4mm yet, that might be more challenging. I do these with lots of flux and a chisel tip and remove any bridges with braid and then reflow the joints with hot air and inspect under a microscope. I've found the SOIC chips and 0.8mm TQFP very easy to hand-solder with a .5mm tip. QFN has been shockingly easy. I apply solder to the pads with flux, flux it again, lay the chip in the appropriate place, apply hot air, and surface tension sucks it right in. I've done that with the QFN32 and QFN64 packages (8U2 and 165). Same process for 1206, 0805 and 0603 components so far - surface tension is your friend.. I haven't done BGA/LGA. Obviously those packages defy inspection which sucks. I guess you just check adjacent pads for continuity (shorts) but I am not sure how you check to make sure the joint itself is good except try them out. Anyone do those? What else is there that I should integrate into a project just to try it out? Is BGA the king daddy of hard to solder packages? I have 3 Atmel BGA-100 packages for my first attempt at that.
I have only come here seeking knowledge. Things they would not teach me of in college.

CrossRoads

FT232R (28 pin TSSOP), but not always.
I have a steel stencil that I will try for applying paste next time I try.
http://www.proto-advantage.com/store/product_info.php?products_id=2220041
Designing & building electrical circuits for over 25 years.  Screw Shield for Mega/Due/Uno,  Bobuino with ATMega1284P, & other '328P & '1284P creations & offerings at  my website.

Grumpy_Mike

Oddly enough it was yesterday. I had got a bi-colour LED and it came in an 0603 package. That meant it had four connections one in each corner of the package. I had to solder it on strip board and I thought I couldn't do it. Anyway I did it.

JoeN


Oddly enough it was yesterday. I had got a bi-colour LED and it came in an 0603 package. That meant it had four connections one in each corner of the package. I had to solder it on strip board and I thought I couldn't do it. Anyway I did it.


Hey, cool.  It turns out I just got a few of these.  The one on my Dragon caught my attention the way it goes from red to green and I thought that would be neat to implement on a project at some point.  Mine are just like yours with the edges being the areas to connect.  Mine are 0805s though so it might be a little easier.  Still, it doesn't look easy with the way connections must be set up though I guess this is the only way to do it.
I have only come here seeking knowledge. Things they would not teach me of in college.

Chagrin

Mine was an LGA-14 (analog accelerometer). Bought them for fun because they were very cheap. Second try I managed to get it soldered on a home-etched board but it started smoking after about 10 minutes because of (I assume) some leftover flux under it.

JoeN


Mine was an LGA-14 (analog accelerometer). Bought them for fun because they were very cheap. Second try I managed to get it soldered on a home-etched board but it started smoking after about 10 minutes because of (I assume) some leftover flux under it.


Hmmm, Sparkfun still selling them

https://www.sparkfun.com/products/9605

Samples are still available, but Freescale doesn't recommend them in new designs for some reason.   :smiley-eek:

http://www.freescale.com/webapp/sps/site/prod_summary.jsp?code=MMA7361LC&tab=Buy_Parametric_Tab&nodeId=01126911184209&pspll=1&fromSearch=false
I have only come here seeking knowledge. Things they would not teach me of in college.

Grumpy_Mike

Quote
but Freescale doesn't recommend them in new designs for some reason

They say that when they are stopping, or have stopped, making the part, it is called going obsolete.

Constantin

32 TQFP, but in a 5mm x 5mm format. Leaves 0.5mm pitch per pin and even with a stencil that is a PITA!!!

Reason being that unless you have just the right type and amount of solder paste, there is so little solder mask between pins to prevent shorts. And when you try to clean up accidental solder bridges with anything but a robotic helper and a giant magnifying glass, you have the joy of observing pins wandering from pad to pad as you brush them with your soldering iron when you try to suck up / drag solder the excess away. Thanks but no thanks, I am never touching those types of chips again, if I can help it.

Osgeld

my finger

not just burned but accidentally soldered a smd resistor to it
http://arduino.cc/forum/index.php?action=unread;boards=2,3,4,5,67,6,7,8,9,10,11,66,12,13,15,14,16,17,18,19,20,21,22,23,24,25,26,27,28,29,30,86,87,89,1;ALL

JoeN


my finger

not just burned but accidentally soldered a smd resistor to it


Did you use flux or not?
I have only come here seeking knowledge. Things they would not teach me of in college.

cjdelphi

Want to take my tafe Soldering Lessons..

I'm sick of bending Resistors to look the way they wanted them to look like, as far as i'm concerned as long as you wet the solder properly and do it right, does it really matter what shape the bloody resistor is! providing there's no chance of it shorting that is....

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