SparkFun Forums

[rowan.bradley]

Hi,

I'm trying to hand assemble a prototype with a few SMDs. They are quite small devices, with up to 8 leads. The method I'm trying to use is to solder a thin tinned copper wire onto each used lead or pad of the SMD, and then use these wires to connect the chip to my prototype board. So far this has been unsuccessful, and has fatally damaged a fairly expensive chip that I've only got one of. This was an LCC8 pack, i.e. a ceramic device that just has 8 plated pads on the bottom of it. It has no physical metal leads - just these plated pads. They are gold, or gold plated. I seemed to solder the wires on successfully, but they pinged off very easily, and in one case they seem to have pulled off or damaged the plated pad. I wonder whether I used too thick a wire, leaving nothing to provide strain relief.
Before I buy another chip and have another go, I need to understand how to do this successfully:

• What type of solder should I be using? Should it be leaded, or lead free? What should its melting point be? What gauge of solder works best?
• Do I need a separate flux? If so, what sort?
• What temperature should my soldering iron be set to?
• What gauge of wire works best?
• Any other suggestions to make a success of this?

Or is this method doomed to failure, and should I try something else?

Thanks for your help and advice - Rowan

[leon_heller]

You might be able to use breakout boards, but a properly designed PCB is the best way to do it.

[motopic]

Glue the part upside down to a piece of perfboard.
Remember you are pinning out in reverse!
Run small bell wire from each lead to a .1 pin. Jump this header to your other devices.

Use a tiny bit of solder paste.

Iron at 350F or so, you need a adj temp iron and a fine tip. 1 sec heat time, 2 at most.