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Discussion Starter · #1 ·
While i was researching this device, i was thinking that one way to get usb charge, was to make your own usb to the devices specific plug cable. now usb doesnt put out much power, so it shouldnt hurt it,in more cases it will most likely charge slower.And today i was looking on this websitehttp://www.shenit.com/eken-m001-7-google-android-1-6-ipad-tablet-slate-pc-umpc-mid-netbook.htmlTo find down the bottomGoogle Android Tablet Computer X 1Dock Connector to USB Cable X 1USB Power Adapter X 1Documentation X 1Now Mabye this company have made there own usb Charger cable?I know its perfectly possible to create, just will the usb cable have enough juice to charge.
 

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Well this device takes in 9volts to charge and USB ports output 5volts so unless you want to use a DC-DC converter and a lot of fiddly soldering it isn't possible. Not to mention the charging circuit might not even kick in with the small amount of power USB delivers. Oh and if you didn't regulate the current draw you would most likely cook your USB controller almost instantly.TL;DR the site most likely got this wrong.
 

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Discussion Starter · #3 ·
Well, Ive got a diploma in Electronic Engineering A while ago.Bit sketchy From what i remember, but i certainly have the skills to Make such a adapter.Also remember USB 3 outputs more power, which i have
.But in all cases, what i was going to do, is try find a Universal USB charger Of ebay. Then mod it to suit my needs.
 

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Discussion Starter · #5 ·
More research I have found something that will most likley Do Great :)A step up Converter For USB, Which is strange, But basically what we want.USB at 5v Can draw a max of 450ma From powered USB slot, this device can output 9v at 300maNow what specs does the m001 need to charge? i know it needs 9v input voltage, but what about current?http://www.welovemacs.com/zipcellb9v.htmlhttp://www.seeingwithsound.com/usb_powersupply.htmIf i can find this wiked device it would be really easy to mod.That is if 300ma is enough?
 

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Discussion Starter · #8 ·
Ok, Found out a store that sells that usb 5v to 9v step up And ships to australia.http://www.swamp.net.au/store/universal-usb-mobile_phone-car-wall_pc-charger.htmlFor anyone interested.It comes with other random shit, but hey...if i can get this thing to charge via usb, i think i would actually use it more!.I also found a guy who was basiclly looking for the same thing ( pre made and not have to make ur own circuit)Here http://blog.tomw.net.au/2009/08/powering-12-volt-router-from-usb.htmlHe basiclly wanted to Power a Modem Off Usb, Which wanted 12v, He tried of 5v using USB, didnt work.He used that same usb to 9v thing to power a 12v modem at 9v, so it seems that the box does indeed stepup the voltage.I just hope it isnt dirty voltage.but anyway, i will buy that usb to 9v thing soon, and hopefully i get it when i get my m001
 

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[quote author=jayrod link=topic=75.msg588#msg588 date=1273997231]USB at 5v Can draw a max of 450ma From powered USB slot, this device can output 9v at 300maNow what specs does the m001 need to charge? i know it needs 9v input voltage, but what about current?[/quote]The charger with the M001 says 9V at 1.5 amps.
 

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Possible solution is using a dual usb cable in series (5v + 5v) and placing a diode in series to create a voltage drop of 0.7v to provide 9.3v with 450ma for power. Anyone want to back me up with this, or add ideas?
 

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All the dual head usb cables I've seen and have are for increasing available amperage (current). A single USB is rated for 500ma max, and most laptop hard drives are rated to draw max of 500ma, so its a good idea to have more available power by using 2 USB in parallel. Most common dual head USB are for external enclosures for 2.5" laptop hard drives.USB 1 = 5V at 500ma USB 2 = 5V at 500maWhen connected in series you'll get 5V at 1000ma (1amp)When connected in parallel you'll get 10V at 500maTaking a commercial dual head USB designed for increased power and rewiring one USB adapter by swapping the positive and neg power wires will yield increased voltage. Since the Eken M001 input voltage is rated at 9v, adding a diode will create a voltage drop and reduce USB voltage available to 9.3v. Only variable we don't know is what is the max power draw by the tablet? Is it more than 500ma?If anyone finds a cheap dual head usb cable, please post here a reply.
 
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