For higher current traces, is there such a thing as a metal bar that can be used?

[NVergunst]

I am designing a power supply that has a few higher amperage traces (10A-20A DC @ 5v-12v) and it is on a fairly high density small area board. I was thinking there must be a way to make one of the traces basically all solder (like a giant pad) then solder on a metal bar or solid core wire or something of the sort. Is there a standard name for this, or is this doable/feasible?

What about doing the above sans actual metal bar? Would the added thickness of the solder paste help any or would it be detrimental without something else there?

 

[alexan_e]

I fill the traces with solder like in this picture (no wire)


Or you can also remove the insulation from a single core wire, place it over the trace and then fill/solder the wire

Alex

 

[NVergunst]

I fill the traces with solder like in this picture (no wire)


Or you can also remove the insulation from a single core wire, place it over the trace and then fill/solder the wire

Alex

Hi,

I have done that before, but this is for a real production board. Something that will be pick-n-placed at some point after prototyping. I don't think the machines will do that. I could be wrong about that though.

 

[alexan_e]

Yes, I'm using it for hobby circuits, I thought that this was your intension too.
I haven't seen any production board so far using bars or something like that but they may exist, I suppose it is a good solution but can't be automated easily.

Alex

 

[mtwieg]

I've never seen something like that done on a PCB. Generally high current paths are either bus bar screwed directly onto the PCB with standoffs, or are shorts runs of wires with either terminal blocks or ring terminals.

I also wish there was a way to do what the OP is describing in a production assembly. There's no reason a reflow machine couldn't do it. But the problem is with the component placing; most machines just couldn't handle placing a long thin piece of wire on a board. It would have to be done by hand.

Maybe you could just get away with leaving a wide trace bare, and printing a layer of solder on it, and just reflowing that? Worth a shot.

 

[FvM]

Resitivity of tin is a multiple of copper, lead alloy is even worse (about tenfold copper resistance), so it's no particular promising, even in DIY designs.

Bus bars have been used in conevntional assembly since long, like this parts

CCI's Standard Copper Rigid Bus and Brass Board Stiffeners
**broken link removed**

I'm not aware of particular SMT dedicated bus bar products. But I don't see a problem to reflow solder plain or tinned copper bars to a PCB.

 

[Orson Cart]

copper parts can be etched just like a pcb (0.2 - 0.5mm thickness) with suitable "legs" to go thru holes in a pcb to carry high current to any part of the board - the copper parts can be folded and can be quite elaborate if required (limited only by imagination of designer) or very simple - usually they are plated with solder ("tinned") - there are quite a few suppliers that do these, and can be stamped brass for high volume. Regards Orson Cart.