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[Q] Voltage on unofficial micro USB charger

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By paddyb, Member on 4th April 2011, 11:53 AM
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13th November 2011, 08:18 PM |#11  
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I fear it's not that simple, especially with dumb chargers that can't negotiate current using the USB protocol, and instead may short the data lines, in various ways, instead to tell the device what current to draw...

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15th November 2011, 04:12 PM |#12  
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There's an explanation here of why different chargers do indeed make a difference:

http://en.wikipedia.org/wiki/Usb#Power

see in particular the note on the Battery Charger Spec.

In particular. my own testing shows I can go from 500ma to 700mA charging current simply by changing a small connector in line between the 7Ahr battery I'm using to charge the phone, and the phone. That's due to the nature of the short on the data pins.

There are proprietary tweaks to this mechanism; e.g. iPhones use voltage signalling between the two data lines and ground to indicate various things to the device.

All of this is only for "hosts", i.e. chargers etc, that don't implement the USB protocol and so can't engage in the normal current negotation that occurs when connecting e.g. the device to a PC.
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26th June 2012, 03:52 PM |#13  
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Would i **** it up pluging a 5.8 volts solar charger on my phone?
18th July 2012, 10:57 AM |#14  
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Originally Posted by projeto56

Would i **** it up pluging a 5.8 volts solar charger on my phone?

It's a bit too high.
You have to know that slow charge = long battery life and fast charge = more battery drain after a couple of years maybe months
18th July 2012, 12:09 PM |#15  
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Quote:
Originally Posted by HdX75

It's a bit too high.
You have to know that slow charge = long battery life and fast charge = more battery drain after a couple of years maybe months

So usb charging is better then wall charging with original charger? because i noticed that my phone hold it`s charge better if i use the wall charger.
18th July 2012, 03:37 PM |#16  
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Originally Posted by Pezmet

So usb charging is better then wall charging with original charger? because i noticed that my phone hold it`s charge better if i use the wall charger.

Maybe because the current is higher. My battery voltage is arround 4200mV at 100% and 4100mV with USB
For the solar charger 5.8 is really high but the wall charger is ok
9th May 2018, 07:05 PM |#17  
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guys can anyone tell me what would be the reason that my Samsung j7 prime charger is giving me 4.63v instead of 5v .. the rating is 5v on the charger. is that possible the ic or some other thing is damaged? in that case what would be solution?
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charger, unbranded, universal, unofficial, voltage

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