EE/CE guys, got a PCB trace fix question

[halik]

I'm fixing my plasma tv and I managed to lift/remove a bunch of trace for a SMD chip (pretty high density). Can i use a trace pen to fix the leads and then solder the chip back onto the trace-pen contacts?

edit:
this


edit 2:
Found this guy, supposedly solderable pen
Text

 

[Iron Woode]

wrong forum?

 

[PottedMeat]

Originally posted by: halik
I'm fixing my plasma tv and I managed to lift/remove a bunch of trace for a SMD chip (pretty high density). Can i use a trace pen to fix the leads and then solder the chip back onto the trace-pen contacts?

edit:
this

Hmm I don't know, never tried soldering on trace pen before - I would think the heat would screw up the new traces.

I'd just scrape off a portion of whats left of the trace clean to expose the copper. Take a long (~1"+) strand of stranded wire and solder it on. Do the same to the other side and see if you can solder the ends of the strands to the SMD chip. Its even easier if one pad of the chip is still there.

 

[FreshCrabLegs]

*

 

[halik]

bump

 

[halik]

Originally posted by: PottedMeat

Originally posted by: halik
I'm fixing my plasma tv and I managed to lift/remove a bunch of trace for a SMD chip (pretty high density). Can i use a trace pen to fix the leads and then solder the chip back onto the trace-pen contacts?

edit:
this

Hmm I don't know, never tried soldering on trace pen before - I would think the heat would screw up the new traces.

I'd just scrape off a portion of whats left of the trace clean to expose the copper. Take a long (~1"+) strand of stranded wire and solder it on. Do the same to the other side and see if you can solder the ends of the strands to the SMD chip. Its even easier if one pad of the chip is still there.

Not gonna work, the leads are super dense. I'm much better off redoing the pads and then reflowing the whole thing

 

[Leros]

Originally posted by: halik

Originally posted by: PottedMeat

Originally posted by: halik
I'm fixing my plasma tv and I managed to lift/remove a bunch of trace for a SMD chip (pretty high density). Can i use a trace pen to fix the leads and then solder the chip back onto the trace-pen contacts?

edit:
this

Hmm I don't know, never tried soldering on trace pen before - I would think the heat would screw up the new traces.

I'd just scrape off a portion of whats left of the trace clean to expose the copper. Take a long (~1"+) strand of stranded wire and solder it on. Do the same to the other side and see if you can solder the ends of the strands to the SMD chip. Its even easier if one pad of the chip is still there.

Not gonna work, the leads are super dense. I'm much better off redoing the pads and then reflowing the whole thing

Use magnet wire. You can get it extremely thin and the coating melts right off when you solder it.

 

[blahblah99]

What kind of SMD chip is it? And what's the density? BGA? SOIC? 0.5mm pitch?

You'll most likely have to clean up the traces by cutting them out and soldering on thin wires from the leads to the traces. Make sure you use an exacto to clear off some of the soldermask.

Unless of course, if the chip is a BGA then you're screwed.

 

[CallMeJoe]

Originally posted by: Leros
Use magnet wire. You can get it extremely thin and the coating melts right off when you solder it.

I wouldn't say the coating "melts right off", but it's not hard to scorch through it with an iron. I've done a lot of PCB repairs; copper foil tape works great for wider paths (like power traces) and mag wire for signal. Also get some conformal coating to seal the repaired area (electrical insulation and protection from humidity).

 

[Rubycon]

Need a pic or two.

 

[halik]

Originally posted by: blahblah99
What kind of SMD chip is it? And what's the density? BGA? SOIC? 0.5mm pitch?

You'll most likely have to clean up the traces by cutting them out and soldering on thin wires from the leads to the traces. Make sure you use an exacto to clear off some of the soldermask.

Unless of course, if the chip is a BGA then you're screwed.

0.5mm pitch 4 sided TSOP
Plan B is small wires, but i'm hoping i can use that silver pen to just fill in the grooves that the traces left.

this guy looks promising