Is it Possible to Hand Solder a S-PDSO-G8 package?

Thread Starter

iBeta

Joined May 15, 2014
3
I have never hand soldered such a small package before. Wondered if anyone has tried, or else knows it is definitely a waste of time?
This is just for a prototype, but I would still need to do around 6 of these.

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ThePanMan

Joined Mar 13, 2020
433
the QFN package ••• is tricky.
I wave solder them with a large tip and drag molten solder across all pins. The result is that most pins do not have bridges when properly and generously fluxed. The last 2 or 3 pins always bridge. But a little solder wick to remove the bridging then another pass along the QFN leads moves just enough solder to make class 3 acceptable solder joints.

I start by soldering one corner. Then I manipulate the chip till the opposite corner is correctly aligned. Then I go back to the first corner and again heat the solder and adjust the QFN till it's in proper orientation. Then I tack a third corner, then the fourth. Then I wave them as described above. Each side one at a time and the dwell time is less than half a second. Solder wick to clean up any bridging and you're done.
 

BobTPH

Joined Jun 5, 2013
5,251
Ok, thanks for the confirmation. I guess flux on the pcb pads/bottom of pins, solder over the pins and remove using solder wick?
That is how I do it. The hard part is to keep it aligned. I tin two opposite corner pads, align it carefully, then touch the pins with the soldering iron to tack it down.
 

Thread Starter

iBeta

Joined May 15, 2014
3
That is how I do it. The hard part is to keep it aligned. I tin two opposite corner pads, align it carefully, then touch the pins with the soldering iron to tack it down.
Great, hopefully it will ok, I mean there are only 8 pins to your 44. I still miss the DIP packages though, drilling aside.
 

MisterBill2

Joined Jan 23, 2018
12,431
I tin the pads and leave a very thin film of solder by removing most with solder wick. Then position it and heat the tabbs one at a time with the iron point, doing the corners first. Thus I don't need to clean up excess solder. A very fine point iron and a very good magnifier are required.Alsi steady hands.
The really miserable part is the 01 by 01 diode. They often tend to get reversed.
 
Last edited:

ThePanMan

Joined Mar 13, 2020
433
I tin the pads and leave a very thin film of solder by removing most with solder wick.
Thus I don't need to clean up excess solder.
Soldering then wicking? Sounds like you're doing what you say you're not doing. Unless I'm misunderstanding something.

With boards that have been silk screen soldered there's usually the proper amount of solder present. Positioning a chip in the correct orientation then reflowing just one corner lead while pressing down with not too much force will hold it in place. Then do the same at the opposite corner, coaxing the chip into the proper placement on the pad. Then reflow the first pin again to relieve any stress from alignment movement. Then reflow every other pin down one side, then every other pin down the other side. Then go back and solder the pins that were missed. That way you don't put too much thermal energy into the chip in any single location, giving it a chance to cool between solder iron touches.
 

MrChips

Joined Oct 2, 2009
26,512
Try to avoid solder bridges in the first place. Use the finest solder wire and soldering tip you can find.
I find that it is difficult to remove bridges afterwards even with solder wick braid.
 

Ian0

Joined Aug 7, 2020
5,533
I tin the board with plenty of solder then solder the IC with a hot air rework tool.
I bought a set of soldering iron bits, which included one which looked like a knife-blade and never did work out what it was for.
I still don't know but it is really good for tinning surface mount pcbs.
 

MisterBill2

Joined Jan 23, 2018
12,431
Some solder removal braid products work FAR BETTER than some other brands of products. I have observed that a few times. There are indeed cheaper brands that do not work as well. In addition to that, it takes the right shape of iron tip at the proper temperature to work really well. Those products are not all the same.
 
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