Dell Inspiron N5030 external power idea

[Ant3G]

Original adapter from that laptop got burned while it was powered and working while outside was bad and thunder weather. Laptop is working on charged battery but not working on any replaced adapter, even tested on same original adaptor.
I got one idea but not sure if it is possible, help me with that please.
If i connect external power supply with exactly 12v on + / - pins through battery side, will that laptop work normaly? (battery got 11.1v, ist probably 3.7v * 3)
I dont have equipment to test mosfets and dont want to disassembly whole laptop. Laptop doesnt need to be moved constantly, and external power supply made by this could be fine to use, ofc if it is possible.
Help please
Thanks

Sorry for any english text mistakes.

[b700029]

Re: Dell Inspiron N5030 external power idea

Maybe, maybe not. The battery is a "smart" battery which communicates with the EC in the laptop via SMbus signals. Maybe it'll continue to work despite the software thinking there's no battery nor adapter plugged in, or maybe it won't power on at all without the proper SMbus communication taking place.

Surely you would have a multimeter? That is enough to test MOSFETs and trace the input power circuitry. I can't find the schematic right away but if you post some detailed pictures of the motherboard's power section we can point out where to look. They're all based on common switching regulators and rather standard. Maybe you just have a blown fuse.

[Ant3G]

Re: Dell Inspiron N5030 external power idea

Ok, here are the pictures. Mbo from upper side looking good, nothing unusual. Everything clear. Mbo from down side got burned in one place. That is fuse i guess? Whats its rating? Can i connect it directly with wire? Suggest me what to do. Got good solder iron, got little experience, got multimeter.

[b700029]

Re: Dell Inspiron N5030 external power idea

I can't read the numbers on any of the chips.

Please try again with the pictures, this time with the camera perpendicular to the board and the edges aligned with that of the board.

[Ant3G]

Re: Dell Inspiron N5030 external power idea

I hope it's better now. Cant get better than this, pics are taken with mobile phone SGS i9000. Dont have better camera here atm but if needed will borrow.

[b700029]

Re: Dell Inspiron N5030 external power idea

The first one is great. I can see the numbers on the MOFSETs.

The other two are useless.

Take pics of the other areas of the board in the same way as the firstone.

[Ant3G]

Re: Dell Inspiron N5030 external power idea

Whole board from down side.

[b700029]

Re: Dell Inspiron N5030 external power idea

Did you remove U5701 and if so, what was it?

I see all the power MOSFETs, the network chip (Atheros AR8152), clock generator (ICS 9LPRS356AKL), and embedded controller (the Nuvoton), but not the battery charger/system DC-DC converter chip. Can you give pictures in the same way for the other side?

[Ant3G]

Re: Dell Inspiron N5030 external power idea

No, I didnt remove anyting. All is as it was.

[Ant3G]

Re: Dell Inspiron N5030 external power idea

Couldn't edit post. Delete upper post if it's against rules (double posting).

Pictures of up mbo side.

[b700029]

Re: Dell Inspiron N5030 external power idea

With the exception of the TPS51620 (vcore controller, 5V input, not too useful for what you want to do) I can't read the ICs. You will either need to provide clearer pictures or read what these say.

[momaka]

Re: Dell Inspiron N5030 external power idea

Mbo from down side got burned in one place. That is fuse i guess? Whats its rating?

Nope, that's a ceramic cap. You can tell by the board markings (the "C" in C6103 stands for capacitor).

Ceramic capacitors like to short out when they die. Remove it from the board and test it with your multimeter using the lowest resistance setting (usually 200 Ohm on manual multimeters). You should get an open circuit across the cap terminals. If you don't, post what readings you get.

[Ant3G]

Re: Dell Inspiron N5030 external power idea

Ok here are names.
I dont get any ohm/esr readings from capacitor.

[b700029]

Re: Dell Inspiron N5030 external power idea

Thanks, now we know what you're working with.

Googling the part numbers lead me to the N5010 schematic which seems very very similar to yours. It's good enough to follow when checking the components, at least. Go to page 45 and start tracing power.

TPS51116 - DDR supply
TPS51218 (likely match for the PIZI part) - 1.05V VTT supply
TPS51125 - main system supply (in the N5010 it is replaced with the RT8205, apparently a Chinese clone with the exact same pinout.)
TPS51620 - Vcore supply (in the N5010 it is replaced with the ISL62883, possibly having the same or similar pinout.)
BQ24745 - battery charger
EMC2102 - fan controller

[momaka]

Re: Dell Inspiron N5030 external power idea

I dont get any ohm/esr readings from capacitor.

Is that out of circuit or in circuit?
Also, what exactly do you mean by no reading? Zero Ohms (as in 0.000) or open circuit (on auto-range multimeters, open circuit is displayed as "OL" and on manual multimeters it's "1" on the left side of the screen)?

[Ant3G]

Re: Dell Inspiron N5030 external power idea

I get reading like there is no contact. I get "1" at display while multimeter is not connected to anything, and when i connect, its still 1, no change, no contact. Same thing on board and also when measured board when cap was removed.
Today but little later will start tracing voltage. Thx

[Ant3G]

Re: Dell Inspiron N5030 external power idea

Just changed cap on board and still same problem. But I found something. When power adapter is connected to MBO, USB and power connectors are getting hot. What that means? All voltages near ac connector are low, <0.5V

[b700029]

Re: Dell Inspiron N5030 external power idea

That means there is a short somewhere. Look for hot component(s) on the board.

A low-voltage high-current power supply will be useful for tracing shorts.

[Ant3G]

Re: Dell Inspiron N5030 external power idea

I think I will abort fixing this board. Seems impossible to me to find where is it shorted.
Could this component be the cause? Its so hot that i cant hold finger on it.

[b700029]

Re: Dell Inspiron N5030 external power idea

That's just the input reverse-polarity-protection diode.

It getting hot only shows there is a short somewhere.

You need a low-voltage current-limited supply, a multimeter, and soldering iron to find it.