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kinshi_lp
Sep 1, 2009, 09:39 PM
Hi.anyone,help! My laptop charger is 18.5V output but it's cut.Im working on something urgent so for the mean time can I use a lesser Voltage of 8.5V to charge it? Please advise me

Bill-K
Sep 1, 2009, 10:04 PM
I don't think you would be doing any harm by trying 8.5V - but I doubt if that is high enough to work. I would expect you to need at least 12V.

Also - I am assuming here that your original laptop charger is DC (Direct Current). Be very careful that any other power adapters you try using are producing DC - and NOT AC (Alternating Current). I think if you use AC, you run the risk of damaging your battery.

kinshi_lp
Sep 1, 2009, 10:28 PM
Sir Bill,thanks for answering... my laptop charger is AC,also with the other one.. how about if I take out the battery and try running it on with the lesser voltage,would it do any damage on my laptop?I won't try doing it unless you approve of it

Bill-K
Sep 2, 2009, 12:38 AM
I think I may need to be a little clearer here. I'm not talking about the INPUT curren/voltage of your charger here. That will deffo be AC, and either 110 or 220 V - or whatever your local mains supply is. It's the OUTPUT that needs to be checked.

I've done electronics in my time, but power supplies is not really my domain - so I am NO expert here, Kin. I would, however (if there was nobody else looking) try doing what you suggested, before giving up. Taking the flat battery out of the equation will - in theory - mean less of a drain on the 8.5V supply. And you MIGHT - JUST MIGHT - be lucky!!

Be lucky, my friend!! :)

kinshi_lp
Sep 2, 2009, 01:07 AM
I think I may need to be a little clearer here. I'm not talking about the INPUT curren/voltage of your charger here. That will deffo be AC, and either 110 or 220 V - or whatever your local mains supply is. It's the OUTPUT that needs to be checked.

I've done electronics in my time, but power supplies is not really my domain - so I am NO expert here, Kin. I would, however (if there was nobody else looking) try doing what you suggested, before giving up. Taking the flat battery out of the equation will - in theory - mean less of a drain on the 8.5V supply. And you MIGHT - JUST MIGHT - be lucky !!!

Be lucky, my friend !!! :)

****
thanks Sir Bill,I've tried it and your right,power output is not enough(8.5 vs 18.5; big difference) hence it won't charge... thanks a lot for your time,appreciate it =)

Bill-K
Sep 2, 2009, 01:18 AM
Sorry it was a no-go, matey.

ComputerHelpers
Sep 3, 2009, 12:41 AM
Actually, the input for the on board lower level tolerance voltage runs in the 13.7 vdc range, since there are on board dc to dc converters. Anything less will make the m/b useless. And that's from designing SMPS for ocmpututers for around 25 years.

Bill-K
Sep 3, 2009, 12:57 AM
Thanks ComputerHelpers, it's encouraging to know that my guess was at least in the ball park. As it comes from a power supply designer, I guess we can call that the definitive post here!!