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wireless charging overvoltage

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slojko
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Default wireless charging overvoltage

I picked up a wireless charger the other day and when I used it I noticed my phone was pretty hot after. Hotter than normal USB charging. I went to read the manual that came with it and it said the maximum input voltage was 5v and I was using a wall USB outlet that outputs 1000mA which is about 9v , I know that's bad but would have damaged my phone at all or only my wireless charger??

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mmmmBACON
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Quote:
Originally Posted by slojko View Post
I picked up a wireless charger the other day and when I used it I noticed my phone was pretty hot after. Hotter than normal USB charging. I went to read the manual that came with it and it said the maximum input voltage was 5v and I was using a wall USB outlet that outputs 1000mA which is about 9v , I know that's bad but would have damaged my phone at all or only my wireless charger??
Neither.

A wireless Qi charger will be warmer overall than corded charging, it's nothing to worry about (try playing a graphically intense game for an hour on the Nexus 5, that's heat).

When the charger says it will take 5V input, that is how much it will draw. For example, if an adapter outputs 12V, that's how much it can provide, NOT how much it is forcing in to a device. So the Qi charger is drawing 5V out of the 9V your USB wall charger can provide. The other 4V aren't utilized.

Same concept for example on a desktop computer. If you have a 1000W power supply and your computer is in sleep mode, you power supply is not shoving 1000W forcefully through the computer. So your computer is using like 100W and the remaining is available when needed but not active.

Don't worry, you're all good.
 
picard782000
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Sorry but that's not correct.
If you have a device which is rated with a voltage of 5V and you connect a power supply with 9V you could damage this device.

The voltage has to be correct. Always!!!
The max current of the power supply can be higher than the rating on the device.

For example your original charger says 5V 1A. You can use a charger with 5V and 3A. Your device will draw only as much current as necessary.
But the voltage always has to be correct.

In case of the qi charger:
If you power the qi charger with 9V instead of 5V you could kill the charger, but not the telephone.

Gesendet von meinem Nexus 5 mit Tapatalk
 
premo15
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How did you get 9v? In North America mains outlets provide about 120v and in Europe they output about 230v. That being said, I would think that the ac adapter that came with the charger would reduce the voltage to within the needed range (~5v). I'm no electrical engineer though, so someone correct me if I'm wrong...

Sent from my Nexus 5
 
tjpallares
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Quote:
Originally Posted by premo15 View Post
How did you get 9v? In North America mains outlets provide about 120v and in Europe they output about 230v. That being said, I would think that the ac adapter that came with the charger would reduce the voltage to within the needed range (~5v). I'm no electrical engineer though, so someone correct me if I'm wrong...

Sent from my Nexus 5
Yeah I think all usb chargers are 5v

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mmmmBACON
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Quote:
Originally Posted by picard782000 View Post
Sorry but that's not correct.
If you have a device which is rated with a voltage of 5V and you connect a power supply with 9V you could damage this device.

The voltage has to be correct. Always!!!
The max current of the power supply can be higher than the rating on the device.

For example your original charger says 5V 1A. You can use a charger with 5V and 3A. Your device will draw only as much current as necessary.
But the voltage always has to be correct.

In case of the qi charger:
If you power the qi charger with 9V instead of 5V you could kill the charger, but not the telephone.

Gesendet von meinem Nexus 5 mit Tapatalk
That's what I meant, my wording was just incorrect. His USB wall adapter was not forcing a higher voltage, but providing more available power if necessary.
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