Using SMD in protoboard

[PEU]

I would like to know if someone found a solution for using smd integrated circuits in a standard protoboard, an adaptor , a clip, any solution?

I know tht using adaptors in step-up /booster / regulator adds noise to the circuit thus reducing eficiency, but it sure helps getting close to the sweet-spot.

Hints wellcome /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/confused.gif /ubbthreads/images/graemlins/confused.gif

 

[PhotonWrangler]

[ QUOTE ]
Pablito said:
I would like to know if someone found a solution for using smd integrated circuits in a standard protoboard, an adaptor , a clip, any solution?


[/ QUOTE ]

Go to Digi-Key's website and look for "Surfboards." They're surface-mount adaptor boards that come in several form factors and allow you to convert an SMD chip to something that you can solder leads to.

 

[Ocelot]

I know this doesn't answer the question you asked, but you can order cheap PC Boards from expresspcb.com. The cost is $59 for 3 small double-sided boards. Whatever you can fit on one board is duplicated onto the 3. If you find enough people, you could get 3-9 different designs on one board.

I had never done a PC board before, and went ahead and designed one for a 5W step-up current regulator. I fit 4 of the regulator designs on a single board, so I got 12 PC boards for $59. Since I ended up making a bunch of lights for people who really liked them, it didn't cost me anything.

Just a suggestion...

Scott

 

[Doug Owen]

I'd like to second what Scott just said. ExpressPCB is for sure '(new) user friendly'. First rate boards, extra heavy clad and plating.

FWIW, I'd suggest trying to keep all between circuit cuts straight so you can go with either a saw or (better still) a shear.

Doug Owen

 

[dat2zip]

Dead bug it on bare copper board. Fast, simple, cheap and is very quiet with a solid GND plane.

 

[MrAl]

Hello there,

They make 'sockets' for SM ic's but they are extremely
expensive (like 100 bucks each). I'd have to try and
find them again on the web.

Take care,
Al

 

[bikeNomad]

I've used the Surfboards before, but in switching circuits you really need to put the inductor, caps, switch, etc. all close together.

I'd recommend one of:<ul type="square">[*]"dead bug" (i.e. glue and/or solder the parts down upside down on a piece of blank copper-clad PC board, with the foil used as ground)
[*] make quick prototypes using the "toner transfer" method if you have a laser printer. I use this a lot with the Eagle PC board program and my cheapo laser printer, and glossy inkjet photo paper (I had to try a few kinds before I found one that worked reasonably well). There's an investment in the etching chemicals, but they last a long time. See
http://www.fullnet.com/u/tomg/gooteepc.htm or http://www.semis.demon.co.uk/PCB/PCB.html for commercial transfer material
[*] use thicker double-sided blank PC board material; use the back side as a ground plane, and cut lines into the top side with a Dremel grinder to isolate pieces of copper to make the circuit. This works fine for the power conductors in switchers, but not for little IC leads, so you can combine dead-bug methods with it. For example, using a SO-8 package you can bend up all the leads except for the ground and high-current leads, then solder those leads down to the big areas of foil that you made with the Dremel. The lower-current leads then get run via wires or other components above the board.
[/list]

 

[PEU]

Thanks for all the replies!

regarding the online service, I live in Argentina so, shipping is overkill, it cheaper an faster here (I guess)

regarding the dead bug method, I don't quite understand it:

using a single side pcb board I glue the components upside down on the copper side or the other?
then you suggest to wire all the connections?

please (dat2zip & bikenomad) explain a little more this method.

Thanks

 

[trailhead]

[ QUOTE ]
Pablito said:

please (dat2zip & bikenomad) explain a little more this method.

Thanks

[/ QUOTE ]

I didn't know either so I Googled it. Lots of info out there.

Duane

 

[PEU]

Thanks trailhead, I googled it but with fewer words and the results were dissapointing. I should had figured out that the an upside down chip looks like a dead bug...

 

[earl]

I have heard (but not tried) that one can solder surface mount parts using a toaster oven. I seem to remember you put solder paste on the pads and then "pop it in the oven". I can't remember if you put it in a cold oven and then turn it on, or what. You might search on tha topic. Good luck. I've had good results hand soldering, but it takes a steady hand and good eyesight.

 

[LEDMANIA]

I also have no idea how this solder paste work on the pcb. Is it a low melting point lead? or an alloy of different low melting point metal.Just want to know co'z chips dont fry when using a hot air soldering tool.. /ubbthreads/images/graemlins/rolleyes.gif

 

[PEU]

surely its lowtemp or you will overbake the components.

Because tin/lead solder alloy 63/37 melt & solidifies at 183 Celcius (361F).
This solder is eutectic, which means that it liquifies/solidifies at the same temperature, and is usually used in machine soldering, as oposed to 60/40 which is used in manual operations.

my 2 cents

 

[Ocelot]

I talked with someone at work who has used the toaster method. He said:

1) You don't want to use the toaster for food afterwards.
2) It really doesn't work.

Scott

 

[bikeNomad]

[ QUOTE ]
Ocelot said:
I talked with someone at work who has used the toaster method. He said:

1) You don't want to use the toaster for food afterwards.
2) It really doesn't work.

Scott

[/ QUOTE ]

Having also used the toaster oven, I'd disagree with the "doesn't work" part.
I've had very good results with one.

As far as not using it for food afterwards, that's a good idea.

At least around here, you can get used toaster ovens really cheaply at the thrift stores.

But there are some problems with solder paste and toaster ovens:<ul type="square">[*] you have to do temperature profiling (I used a thermocouple probe and watched my meter)
[*] solder paste has a limited shelf life (store it in the refrigerator for somewhat longer)
[*] putting the solder paste down in the right places can be as difficult as hand soldering
[*] the toaster ovens don't have enough heat to really get the temperature profile you want anyway (but if you take two old toaster ovens and add the elements from one to the other for double power it helps)
[/list]

 

[Ocelot]

Hmm.

> Having also used the toaster oven, I'd disagree with the "doesn't work" part.

And then

> the toaster ovens don't have enough heat to really get the temperature profile you want anyway

It sounds like you essentially agree with my co-worker's statement, unless you qualify it with "modified toaster oven".

Personally, I've been using a soldering iron my dad bought me back in 1976, and I've been soldering custom SMD boards and haven't had any problems.

Scott

 

[PhotonWrangler]

[ QUOTE ]
Ocelot said:
Personally, I've been using a soldering iron my dad bought me back in 1976, and I've been soldering custom SMD boards and haven't had any problems.
Scott

[/ QUOTE ]

I have a pencil iron with a 1/64" tip for SMD work, along with a spool of hair-thin solder. I've found, however, that I can't do much SMD work after I've had any coffee! It takes an incredibly steady hand to do this stuff.

I've found that tinning the PC board with just the right amount of solder, then gently pressing on the chip while heating up one of the pins will get the thing stuck to the board in reasonable alignment. Then I'll solder one of the opposite-corner pins just to get both ends tacked down, then the rest of the pins are a lot easier.

 

[Ocelot]

Some people at work who do this stuff more than I do recommended using a drop of super glue to attach the parts to the board, then solder later after it has dried. But the fumes from heating up the super glue can be nasty. Best to use a fan.

Scott

 

[PhotonWrangler]

[ QUOTE ]
Ocelot said:
Some people at work who do this stuff more than I do recommended using a drop of super glue to attach the parts to the board, then solder later after it has dried. But the fumes from heating up the super glue can be nasty. Best to use a fan.

Scott

[/ QUOTE ]

I've heard of this trick also, Scott. I wonder if you could also use a dab of melted candle wax to hold it in place? There wouldn't be any nasty fumes or toxic chemicals involved.