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Electronic Circuit Design Help Needed? Answered

I have an HP WebOS TouchPad and the Power adapter has died. I do not want to buy the same changer since it's the 3rd one that has stopped working. Would anyone design the power adapter electronic circuit for me? Also note that if I try any other changer that might have a lower amperage it will not change. AKA I get a screen that says, "use the correct changer outside the OS" Any help would be greatly appreciated.

Power Adapter
Wall AC to USB power adapter, which has input specifications of 100–240 Volt 50–60 Hz 0.4 Amp AC, and output specifications of 5.3 Volt 2.0 Amp DC. It is cylindrical roughly the size of a "D" battery with a foldable 2-prong AC connector and a Standard-A USB socket.

The TouchPad uses a rechargeable 6000 or 6300 mAh Lithium-ion polymer battery rated at 3,7 V (total 22,2 Wh).

More info at


If I understand correctly, you want to take apart the power adapter to fix it. Unless it is a simple task (like a mechanical failure) you might not want to mess with something that contains the power to burn your house down. However, if you choose to do so anyway, be sure that the capacitors are discharged- you could get a nasty zap even if it isn't plugged in.

I would recommend contacting Hewlett Packard- sometimes companies will offer replacements in order to keep up their name (so it may be free). Best of luck.

Service the old one or buy a replacement. Power supply design is vary complicated and complex. Even professional electrical engineers avoid power supply design if they can. As such i will cost you a lot of money to pay someone to come up with a better design. Not to mention the cost to have it made. It won't be something you'l be able to take on your own.

I am with Libahunt.

Open it and post good picks of it.

You may just have a bad connection in the fold out plug.


Have you tried to open and repair it? If it isn't potted with something then repair could be possible whether it is a mechanical breakage or some component failing. If you get it open, post pictures and your observations as new question here. Just don't plug it to the wall while it's open.

Also before everything else test if the problem is actually in the charger adapter or in the USB cable or it's plug-socket contact on the tablet side. (Wiggle the cable and replace with random other good one.)