OT: Laptop PCB repair?

L would be an inductor. it may be an active part of a switching power regulator, or just an EMI suppression part. But, the fact it blew probably means something else has shorted out, and the inductor became a fuse.

Jon

others with "issues". I get a lot of used laptops that I fix-up and donate to people that don't have or can't afford a computer. A cousin of mine works for a nearby suburb and directed their garbage men to save all laptops they find. I also get a bunch, like I did this D600, from customers that upgrade their office equipment.

jack was cracked and loose, I was just careful with it until one day with a bit of side pressure on the plug it poofed a bit of that familial smelling magic smoke. Oops. Now it won't run on AC or charge the battery but will work on a charged battery. So, I take it apart with the intention of finally replacing the power jack. Here's what I find:

to repair this?

Well, it looks like it performed that function. Did something short against something else due to the power jack?

"L-something-something"

An 'L' is an inductor (sometimes a ferrite bead, which is a lossy inductor).

Something like a coil.

Because it wouldn't really help.

Well, if it's to meet EMI standards, then shorting with a strand out of (say) AWG 24 wire it might work (assuming the fault has been cleared). If it's part of a switching power supply then it will probably kill something else. If the fault is still there it will kill something else such as a chip or a trace on or inside the board.

The chances of something else being dead already are pretty good.

Short it if you don't care about the consequences, as a last resort before you chuck it.

Maybe an 0603 (2.1mm x 0.9mm). Relatively large. Good thing it's not an 0401, 0201 or 01005 (0.4mm x 0.2mm)!

hate to sink money into it.

on battery.

Many of the Dells have that special power plug that (IIRC) has an I^2C communication bus to tell the laptop what kind of adapter is being used. Third party adapters will operate the computer but refuse to charge.

Newegg. I had to do some minor surgery on the too-stiff touchpad buttons but I like it and I can play my ?Hidden Object? and puzzle games.

Best regards, Spehro Pefhany

two others with "issues". =A0I get a lot of used laptops that I fix-up and = donate to people that don't have or can't afford a computer. =A0A cousin of= mine works for a nearby suburb and directed their garbage men to save all = laptops they find. =A0I also get a bunch, like I did this D600, from custom= ers that upgrade their office equipment.

ower jack was cracked and loose, I was just careful with it until one day w= ith a bit of side pressure on the plug it poofed a bit of that familial sme= lling magic smoke. =A0Oops. =A0Now it won't run on AC or charge the battery= but will work on a charged battery. =A0So, I take it apart with the intent= ion of finally replacing the power jack. =A0Here's what I find:

deas how to repair this? =A0It looks like it just exploded off the PCB taki= ng the pads with it. =A0I assume it's a current limiter of some sort but th= e silk screening closest to the component looks like an "L-something-someth= ing" =A0What=92s an =93L=94? =A0I assume resisters are prefixed with an "R"= and caps with a "C" so I don't know what the part really is or does. =A0Wh= y can=92t manufacturers just put a replaceable fuse in?

with conductive paint or maybe try to install a discrete component. =A0The = part is TINY! =A0It's less than 3/32" long. =A0

. =A0I hate to sink money into it. =A0I have another D600 that might have t= he same problem, it won't charge but works on battery.

b HP G56 from Newegg. =A0I had to do some minor surgery on the too-stiff to= uchpad buttons but I like it and I can play my =93Hidden Object=94 and puzz= le games.

Basically non-repairable. Those are multi-layer boards and there's no guarantee that if you patch it up on the surface that you'll make contact with the traces inside the board. They might have been vaporized, too. Acer at least puts the power jack on a smaller sub- board, just had to replace one due to the pin in the jack breaking off flush with the bottom of the jack.

It's a surface mount part, through-hole stuff is pretty much obsolete. Usually they're all placed into position by machine with solder paste on the ends and then baked all at once. You have to have some pretty fiddly equipment to properly repair stuff. Conductive epoxy CAN be had, but service info on most laptops is non-existent. Those parts aren't usually sold as onesies, either, even if you could identify what it was. "L" is an inductor, who knows what value.

Stan

An 'L' denotes an inductor. I can't see any printing/colored bands on what remains of the damaged component, so its anyone's guess as to its value.

Its possible (try this only at your own risk) that the laptop may operate satisfactorily if you just jumper across the component's pads. If this inductor was a part of an EMI filter, all you will get is a somewhat higher radiated r.f. noise or susceptibility to power line noise.

others with "issues".  I get a lot of used laptops that I fix-up and donate to people that don't have or can't afford a computer.  A cousin of mine works for a nearby suburb and directed their garbage men to save all laptops they find.  I also get a bunch, like I did this D600, from customers that upgrade their office equipment.

jack was cracked and loose, I was just careful with it until one day with a bit of side pressure on the plug it poofed a bit of that familial smelling magic smoke.  Oops.  Now it won't run on AC or charge the battery but will work on a charged battery.  So, I take it apart with the intention of finally replacing the power jack.  Here's what I find:

how to repair this?  It looks like it just exploded off the PCB taking the pads with it.  I assume it's a current limiter of some sort but the silk screening closest to the component looks like an "L-something-something"  What?s an ?L??  I assume resisters are prefixed with an "R" and caps with a "C" so I don't know what the part really is or does.  Why can?t manufacturers just put a replaceable fuse in?

conductive paint or maybe try to install a discrete component.  The part is TINY!  It's less than 3/32" long.  

G56 from Newegg.  I had to do some minor surgery on the too-stiff touchpad buttons but I like it and I can play my ?Hidden Object? and puzzle games.

Another "Dell from HELL"

The part is an inductor, probably just intended to limit RF emissions on the power wiring; the value is not critical, but it might be difficult to reattach.

Probably the overheating happened after a solder joint cracked due to board flexure (the ferrite doesn't flex at all). The forces on the power cable at the jack can cause this kind of damage, you might want to examine other joints in that area.

You can probably use a ferrite bead for this application; that's a commonly available part. Measurement of the dimensions of the pad and maybe (if someone you know has an LCR meter) metering the component value will suffice to find an 'exact' replacement part.

It is very unlikely that the original part will survive cleanup and resoldering. The pad will have to be fluxed and cleaned carefully because excess force and heat can delaminate the board. I'd use solder wick for that task.

Several places sell the power jack, Dell # DL111500.

My D610 is happy with a Chinese replacement AC adapter, model ST- C-090-19500462CT, from a local store.

jsw

The part is an inductor, probably just intended to limit RF emissions on the power wiring; the value is not critical, but it might be difficult to reattach.

Probably the overheating happened after a solder joint cracked due to board flexure (the ferrite doesn't flex at all). The forces on the power cable at the jack can cause this kind of damage, you might want to examine other joints in that area.

You can probably use a ferrite bead for this application; that's a commonly available part. Measurement of the dimensions of the pad and maybe (if someone you know has an LCR meter) metering the component value will suffice to find an 'exact' replacement part.

It is very unlikely that the original part will survive cleanup and resoldering. The pad will have to be fluxed and cleaned carefully because excess force and heat can delaminate the board. I'd use solder wick for that task.

It looks like both pads were blown off. One looks to still be attached to the component.

Several places sell the power jack, Dell # DL111500.

My D610 is happy with a Chinese replacement AC adapter, model ST- C-090-19500462CT, from a local store.

jsw

The jack was $3 delivered on ebay. I bought it before I shorted the original and blew-up the chip.

I bought an 90W 'Dell' adapter for my Vostro online via Amazon, I think. It came with the "Dell" covered over with stickers (so maybe some shenanigans at the China factory) but looked pretty much identical to the original and works exactly like the original, and for around 1/3 the price.

Best regards, Spehro Pefhany

Remember "Packard Hell" computers? There wasn't a standard piece of hardware ON them. Some of them had rear-mounted power supplies with steel sticks going to the front panel. It was the on/off switch by proxy. I'm glad they're gone.

-- You are today where your thoughts have brought you; you will be tomorrow where your thoughts take you. -- James Lane Allen

Remember "Packard Hell" computers? There wasn't a standard piece of hardware ON them. Some of them had rear-mounted power supplies with steel sticks going to the front panel. It was the on/off switch by proxy. I'm glad they're gone.

-- You are today where your thoughts have brought you; you will be tomorrow where your thoughts take you. -- James Lane Allen

Oh yea, thanks a bunch for reminding me...I'll probably have nightmares tonight.

I like Dell laptops, they are very easy to work on and parts are cheap and available. Want to buy a few?

Is there really much difference between their professional and consumer models?

jsw

My wife has an Apple laptop and they have a neat magnetic DC power connector that prevents damage from yanking on the cord. It would be nice if someone could make a retrofit like this for Dell laptops. Maybe Apple has a patent on the connector that it uses.

You think they were nonstandard? Ever look at the old Olivetti? Same type of switch setup, and the motherboard mounted UPSIDE DOWN.

They were sold under the AT&T label as well. What did you expect from a computer built in Italy?

WHAT? Wouldn't all the electrons fall off? (Or at least all the chips work their way out of their sockets?)

-- To know the road ahead, ask those coming back. -- Chinese Proverb

if you don't count the cables still breaking and shorting out the adapter, it's awesome.

that sounds like those ones sold with the AT&T logo on them.

those things were flat out preposterous in every way possible, but that's what you get when a european typewritter company tries to make a computer.