Notebook Power Adapter blown! Options?

joshuakr

Junior Member
Jun 4, 2004
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0
0
Hi y'all!

My Acer Travelmate 433LC came with a LITEON power adapter rated 19V and 4A

The other day, some power surge in the wall outlet blew me adapter to kingdom come. Thankfully, the laptop wasnt plugged into the power supply.

Now, out where i am rite now, findin a LITEON adapter will mean i go huntin for a looong while. My questions are...

1. Laptops run on DC Batteries rated at 12V rite? So why do i need a 19V adapter?

2. Can i buy an IBM/Compaq adapter that's rated say 15V and 3.5A?


Help needed urgently :-( My next term starts in a couple of weeks...and not havin a laptop will mean i'll be in the poorhouse :-(

Thank y'all in advance for the advice. :)
 

Harvey

Administrator<br>Elite Member
Oct 9, 1999
35,057
67
91
Originally posted by: joshuakr
1. Laptops run on DC Batteries rated at 12V rite? So why do i need a 19V adapter?
Good question. I don't know the circuit design for your machine, but if they use a DC - DC converter, it's possible that any supply within a reasonable voltage range that supplies enough overall power (in watts) will work.
2. Can i buy an IBM/Compaq adapter that's rated say 15V and 3.5A?
Power = Volts x Amps. If my first answer is correct, then the orignal supply provides 76 watts. A 15 volt 3.5 amp supply would only provide 52.5 watts so it would be undersized for your needs.

You also need to know the polarity the connector. If it's the typical coaxial DC connector, various manufacturers use the inner or outer contact as the positive connection. BE SURE which one you have before you plug it in, or you could be looking at a seriously smoked computer.

You don't need the original power supply from Acer, but you need one that meets their requirements. You may be able to find one for less, but unless you feel comfortable understanding the specs, or you can't get an original replacement in time, getting one will guarantee you get one intended to work with your machine.
 

DaWill

Junior Member
May 7, 2004
3
0
0
Alright guys, there is a reason the power supply is 19v. I don't know the reason, but you do not want to run something at a different voltage. Running at a lower voltage should not damage your laptop, but depending on how much lower it is it might not work. Running at a higher voltage can start to blow stuff. The amperage needs to be atleast the amount on your previous power supply. Having extra amperage is not bad because your laptop will only draw the amps it needs.

If you are really don't want to buy a new one online or go around finding one you just have to find a universal one that had the right specs. However, you will need it to have the same connector. I assume your connector from your old p/s is still good, so use it. Cut it off the blown one and cut off the connector on your new p/s and attach the old one. Just make sure the connectors have the same center. You don't want positive going where ground was supposed to.
 

Mark R

Diamond Member
Oct 9, 1999
8,513
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You need to match the voltage of a replacement PSU exactly. The replacement needs to have at least the same current (Amp) rating. Don't forget that there is no standard plug - so that needs to match exactly too.

So you need an adaptor which is 19V and at least 4A (if you can get higher, then that's not a problem - just don't go lower).

The high voltage is needed for battery charging - batteries need more than their rated voltage to charge, and the charging circuit may lose some voltage too. 15V may be enough to power the laptop, but you may find that the battery won't charge (although with a 12V battery, you stand a reasonable chance that it would work). Li-ion batteries don't come in 12V versions - usually they are 14.4V (which cannot be charged with only 15V).

Don't get an adaptor with a higher voltage - it's possible that you could blow some of the circuits in the laptop.