Laptop 90W-120W?

[di4kata]

Hi everyone...I'm in need of a schematic and pcb of a laptop power supply (19V) which can be around at least 90W? Does anyone has something on the subject. Any help is appreciated!

 

[AndrewT]

Hi,
laptop on 19Vdc?
I would expect a mixture of 2.8V, 3.3V, 5V, 12V, some I've missed and a few minuses.

 

[Eva]

Laptops include an internal power supply that charges the battery and derives all the small voltages. External mains adaptors usually provide between 12V and 20V to that internal supply.

Some time ago I had to build a converter powered from 12V for a friend that wanted to charge and use his laptop in his car. The mains adaptor that came with that computer was rated at 20V 4.5A.

 

[di4kata]

Hi Eva! I've also seen the article in Elektor but it's useless to me because I need a mains adaptor. A powerful one!90W but to date havent been able to find a schematic and pcb. There's no hope

 

[mzzj]

I woudnt bother building one as you can buy ready-made products very cheap.

For example car adapters with selectable 15-16-17-18-19-21v output cost around 20euros.

 

[Eva]

He seems to need a mains operated one.

One of those forward converters that you like so much would be fine for that application, and it's somewhat easy to design, but I don't expect him to have the required tools, parts or knowledge.

 

[carvinguy]

Power Integrations has evaluation boards for this very application- maybe a bit underpowered. They use TOPSwitch GX which is an integrated FET with control circuitry all on the same IC for flyback or forward topologies. This may be a good starting point.

They have full schematics and PCB artwork, as well as transformer design and other parts lists.

Here are some links:

www.powerint.com/PDFFiles/epr11.pdf
www.powerint.com/appcircuits.htm#epr31

 

[mzzj]

He seems to need a mains operated one.

I am not that blind.

120w mains operated universal laptop power supplies are something like 60 euros around here.
80w car adapters are dirt cheap, 17 euros

 

[N-Channel]

How about taking an old PC AT supply and re-doing it for 19V? You will certainly get the 90W you want, and then some. Rewind the xfmr and make the appropriate changes in the voltage feedback and overvoltage protection sections. Shouldn't be too hard.

Steve

 

[sivan_and]

Get an old Laptop PSU..replace all elect caps..and u have a good PSu for less $.
There r some half a dozen circuits in various magazines but none seems to have mentioned abt the filter in output leads near the output pin eg:My Sony vaio has a cylindrical black moulded filter..will post pic...later

 

[di4kata]

I thank all of you for the replies. Maybe I'll consider buying a new psu..60 euro seems too much but I have no choice if wanna use my laptop because psu rated 60W(3.9A) isn't enough. The machine just drops dead when I try playing a game or something more demanding of CPU power.

 

[Eva]

Did you understood what mzzj was suggesting? He was proposing you to use some cheap 12V to 19V car adapter that you could then power from an old AT or ATX PC PSU.

 

[di4kata]

heh...then I could just use my lab PSU I need a mobile psu afterall its a notebook right? anyway don't worry...I've posted some ads. Hope someone has one laying around doing nothing and wants to dispose of

 

[mzzj]

Did you understood what mzzj was suggesting? He was proposing you to use some cheap 12V to 19V car adapter that you could then power from an old AT or ATX PC PSU.

Did I?