Laptop power up question?

bigG · 19 Mar 2009 at 21:24

Hello All,

I have a laptop that doesn't power, i have tested the power jack on the mobo for continuity and it failed, so i suspect that this needs replacing.

I just wondered if it is possible to put a small charge into the battery directly to make sure the mobo is ok and the laptop boots, before i replace with a new power jack.

Anyone tried this??

Cheers

G

bigG · 20 Mar 2009 at 22:32

After some research on the web, i think i have answered my own question.

I would have to come up with a circuit board to regulate the voltage and amps, to pulse charge for at least 80min.

Oh well

GeForce · 20 Mar 2009 at 22:49

When you say you continuity tested the jack, what do you mean? If you put one side of the meter to the centre pin and the other to the shield, you shouldn't get continuity. If you do, there's a short circuit.

As for recharging the battery, I have done this with an old NiMH one. I just used a bench power supply to charge at just a few mA for a few hours, at ~2V above nominal battery voltage. After being completely discharged, Nickel tech batteries will be extraordinarily reluctant to hold charge again.

If your battery is a LiPo, you need to be VERY careful if you don't have overcharging/overcurrent protection circuitry in place. If you decide to charge a LiPo without supervisor circuitry, keep the current very low and stay with it whilst it charges. Don't leave it, even for a few minutes. They catch fire all too easily during charging.

NB: If Lithium tech batteries drop below a certain voltage per cell (normally around 1.8V) they will never hold charge again. Attempting to charge them will simply result in a rather nice firework display.

In short, be careful if it's Lithium!

What technology is the battery? What's it's power rating? At what voltage?

bigG · 21 Mar 2009 at 00:18

The battery is a 14.7v 4400mAH LiPo

As for the continuity test i took the laptop apart, and tested from the inner pin to the solder on the board this failed. The outer shell to the board passed.

Thanks
G

da_ging · 23 Mar 2009 at 18:26

if the soldering has gone on the socket it really should be visually quite easy to tell, use a magnifying glass if you have one and a torch

bigG · 25 Mar 2009 at 21:24

I'm pretty sure its the power jack that has failed, Does anyone know where i could source a new one, its for an esystems laptop.

OCUK doesn't sell them, so i'm sure they don't mind me asking.

Cheers
G