Just finished soldering 3 INA226 10 pin SMD .5 mm onto breakout boards.

At first look I thought it would be impossible but when all attempts to acquire the INA226 installed on a breakout board fail, I had to try. Oddly, the soldering part was easy compared to getting that little sucker aligned on the breakout board.

Sticking it down with flux worked for me, but still nerve wreaking. Tinting the breakout board pins is a must.

I may have to check into the hospital tomorrow with nervous breakout.

Tinting the breakout board pins is a must.

Tinting the contacts may make it easier to see them but tinning them makes it easier to solder! :) :)

Weedpharma

Would applying solder paste to the pads, laying the IC down and then applying heat to the pins work? - Scotty

Do you have a desk magnifier? That helps a lot with this sort of thing. Alignment is the most important part. Really, with a decent amount of flux, the solder just knows where to go. Use a chisel tip for this, not a point tip.

Here is a 100 pin 0.4mm IC that I did. No big deal once you get used to it.

PIC24 SMT Soldering Closeup.jpg

When I need to install a surface-mount device, I usually just wet one of the pads with solder, then, holding the device with a good pair of tweezers, I carefully position it over the footprint and heat the solder on that one pad while gently pressing the device down onto its pads.

If the part is misaligned, it's pretty easy to reheat that one pad and nudge the part into proper alignment.

When alignment is good, I then tack down the rest of the pins.

A fine soldering tip (e.g. MetCal), and magnifying lenses or a good stereo microscope (e.g. Bausch and Lomb), help tremendously.

JoeN: Use a chisel tip for this, not a point tip.

This is an interesting tip. Thanks!

I usually use a point-tip, because when I've used a chisel tip I've tended to short multiple-pins together when I'm just trying to solder one pin. But the issue with a point-tip (a fine point tip) is that it doesn't seem to heat the pad/pin as well

But your comment as got me thinking -- if I keep the chisel point away from the IC pins and just heat the pads, there might not be a problem with accidentally soldering multiple pins at once (as long as I use very fine solder), and the pad might heat up more quickly.

jcanderson: This is an interesting tip. Thanks!

I usually use a point-tip, because when I've used a chisel tip I've tended to short multiple-pins together when I'm just trying to solder one pin. But the issue with a point-tip (a fine point tip) is that it doesn't seem to heat the pad/pin as well

But your comment as got me thinking -- if I keep the chisel point away from the IC pins and just heat the pads, there might not be a problem with accidentally soldering multiple pins at once (as long as I use very fine solder), and the pad might heat up more quickly.

You can end up with some solder bridges, but they are easy to deal with. It usually means you are not using enough flux. To get rid of a bridge, 99% of the time I can avoid even using wick. I clean the tip to get the solder off using the metal sponge, wet the bridge with flux, and then use the dry tip to reheat the solder. Extra solder transfers over to the dry tip, reflows the pins underneath the tip, and almost always removes the bridge.

This video shows the drag method with a chisel tip exactly. The guy even gets a few small bridges and then clears them in the way I said. Watch how he uses the flux, that is as important as the solder. All he is doing is wetting the tip with solder and dragging it across the pins.

www.youtube.com/watch?v=tKl23o70iqM

Hot air rework station is wonderful compared to an iron for this sort of work BTW.

I find hot air incredibly useful for small QFN, BGA, SOT, and SOD/0805 and similar two-terminal parts. For larger QFP parts that I showed above, there is no way to heat enough of the part at a time to get it down. However, that small SOP part could be soldered with hot air. For larger BGAs, you have to go with reflow skillet or reflow oven.

+1 Hot air is a must for smd.

I use an old single-pot electric hotplate, and have wired the two elements inside in series for slower heating. And old blob of lead/tin solder in the dimple in the middle of the otherwise flat element acts as a temp indicator. When the solder starts to get soft (~180C), I set the thermostat to "just clicking off". I pre-heat boards for a few minutes, and then I can solder just about anything with hot air in seconds. I mainly use .5mm chips and lead-free solder paste with stencils. A hotplate is also great for recycling smd parts. Leo..