building ac/dc powersupply for laptop...



New Member
My old generic laptop needs a 24v/2.0A power supply. The input consists of 4 pins arranged in a circle.

The old AC/DC power supply is gone and it has proven to be impossible to replace. The manufacturer of the laptop does not exist - i am convinced it was some guy with a soldering iron in his basement. Its called a "SmartBook".

Anyway, i am wondering if it would work to somehow connect 6v/2.0A to each pin. Is it more complicated than this?

Another possible solution is to manually recharge the battery. It is also rather generic looking - its a Ni-MH labeled as 1.2v * 12, 1800mAH. It has 6 pins connecting it to the laptop.

Any ideas? How would i build something that provides 6.0v/0.5A on four separate lines. Thanks.


New Member
Sorry, it is not going to be that easy. Have you had the power supply tested with a voltmeter. Sometimes it is not the charger but one of the plugs. Given that the it is an older unit the batteries may have failed.

Is it possible to dismantle the power supply to see what the 4 pins are connected to. Or how the laptop batteries are wired to the input connection.

A charger can be made, but if you're not familiar with electronics take it to a electonics hobby person or a techie who can see what their looking at for an opinion.

Maybe someone here has a unit that can help with the voltages and the pin connections.


Tazzmanian Devil
I think dell uses the same type of connector that you are talking about. You can always try E-Bay.

Good Luck

~The Devil~

Don't Piss Me Off or I'll Melt Your CPU