Those SMD chips getting on your nerves?

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through hole is driving me crazier

over the years I have gotten pretty good at drilling holes on 0.100 centers, and not breaking my carbide bits, but SMT is so much easier, and SMT 100N and 10N caps are so nice for power supply bypass as they fit right on the traces.

I have a little Weller 12 watt soldering pencil which is great for most SMT, but those BGA's -- you don't want to try this at home if coffee makes you jittery.
 
Havoc said:
Worst mightmare is to have to lift a pin in the middle of a fine pitch LQFP. Or having to solder wires to 5 consecutive pins of one of those. This can take some time.....

Soldering large SMT’s like TQFP’s by hand is easy if you do it the following way:

Use a large (but not too large) regular screwdriver style tip. Now apply sufficient solder and you end up with all pins connected together. Hmm .. not what you intended, is it? This does the trick: Remove the surplus of solder with de-soldering braid like “Soder-Wick”. If you do it right you end up with just enough solder between the pins and PCB traces to make good contact but no shorts between pins. Be careful not to overheat the part. I manage to mount 100 pins, 0.5 mm pitch ones in 5 minutes this way.

;)
 
Soldering them on is no problem at all. Use a bit of flux in liquid form. It is when you have a design problem and want to de-solder a single pin in the middle of a row (without messing up the whole lot or breaking of the pin). 0402 resistors are also nice. And you can have 0201 if you really want..... Great stuff are the die scale mini BGA: a single opamp as a die with 5 balls, no package
 
Havoc said:
It is when you have a design problem and want to de-solder a single pin in the middle of a row (without messing up the whole lot or breaking of the pin

I use that thin (0.1mm thick) stainless steel strip for it. Remove as much solder with de-soldering braid. Then carefully shift the strip between the pin(s) and the board. You have to re-solder the pins besides the pin of interest then.
 
You are welcome I am living in the very centre of Amsterdam.

LOL,

But I know what you mean, also too much coffee…

But the trick is also to pre-heat the stainless steel strip. Hmm… I have to modify an old Weller tip by mounting the strip directly onto the tip :idea:
 
I'm with the guy upthread ... through-hole stuff drives me nuts. It takes so much heat and so much solder to attach anything. Give me nice 0805 passives and I'll be much happier. Happier, and with a better circuit too!

SSOP is getting pretty hard though. I'm glad to stay with SOIC.
 
It's upstairs

great small restaurant.

I've spent days in the Rijksmuseum, usually get to Amsterdam about once per year. Well, I've spent an entire day in the Frans Hals Museum in Haarlem too.

SMD's are better for your health and pocketbook -- you don't breathe fiberglas dust, and you don't break as many carbide bits.
 
Soldering via toaster-oven

the stencil method, I am sure, works nicely.

However, if you have the patience you can get a tube of solder paste from Kester, dab a bit on the board, and using a fine-pointed tool (I use something which looks like a dental pick) apply the paste onto the SMT pads, picking up a little smidgen from the big "dab" and applying to the SMT pads. Then place the devices using a fine tweezer and toast away.

I bought a Black and Decker Oven at Best-Buy for $29. It takes about 5 minutes to heat up to 450 degrees. You can place the board "avec" (that's "cum" for you who speak Latin instead of french) SMT devices and toast for about 2 or 3 minutes. Too much time will cook the board.

Don't try this if you have had more than 3 cups of coffee in the morning.

All you Hollanders, don't try this after your post-prandial schnapps.
 
the board in progress -- i found that it's best to toast it a couple times -- you can see where the "rework" paste allows parts to move a bit (the 2k resistor on the side for the op-amp "disable" function). The solder puddles are where I have put the paste when I work the board.

With the experimentation I have found that it's a good idea to "cook" your work a couple times, check the components to see whether the values change (and that the actives like diodes still Rectify).
 

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toaster oven assembled

when they say "reflow these capacitors only one time" they mean it. all the other devices worked 100% subjecting them to the toaster oven at 450F for 2.5 minutes.

here's the PhaseMeter on the operating table with all the devices installed -- including the "charge hold" capacitor:
 

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I've been changing cell phone backlights recently...
601 SMD led's are pain in the *** to solder - they stick almost to anything - metal, plastic, anything and its nearly impossible to remove static charge from them...
I use 7W pen sized soldering iron, does its job fairly easy. Best thing however is a hot air soldering-desoldering station - handles anything, even BGA, desoldering IC's with many legs becomes a pleasure...
 
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