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Usb charging

owenmorris

iPF Noob
Hi guy's once again, the problem I have is that when I plug USB lead in my ipad2 says not charging. I always do a quick search before posting but found nothing.

Owen
 
It's charging, just VERY SLOWWWWLLLYYY... even though it's saying 'NOT CHARGING'..

the iPad's charge block is rated 10W, and your USB port doesn't push enough power through it for it to trigger the charging icon... that is all..

there is absolutely nothing wrong with your iPad..

when charging on a laptop or desktop, be patient and enjoy... :D
 
Have you connected the USB cable to a pc/laptop?

The iPad draws a current of 10A and only the iPad wall charger supplies this current. A pc USB supplies a much lower current and will thus only trickle-charge the iPad.
 
DontUnderstandMyIpad said:
Have you connected the USB cable to a pc/laptop?

The iPad draws a current of 10A and only the iPad wall charger supplies this current. A pc USB supplies a much lower current and will thus only trickle-charge the iPad.

I hope it's not drawing 10A.... :-). The battery would last only a few seconds if that.

For the OP,

USB only puts out around 5 watts and 1amp. That is why the iPad charges much slower connected to a PC/laptop vise the supplied 10 watt 2 amp power block.
 
@sjleworthy: Using and 'Made for iPad' certified 3rd party charger/USB adapter or the supplied power pack.

Any other method such as connecting to a 'standard' USB port, other iPod/iPhone-only chargers will either (as mentioned) result in a extraordinarily slow charging time or only serve to reduce the battery loss of the iPad i.e. providing enough charge for the current battery level to remain the same or discharge the battery at a reduced rate than normal.

Or if you have money to burn, a new SandyBridge generation MBP USB port will work just as well as the supplied power pack :)
 
Last edited:
Optimal way is always with the supplied charger, but the USB port on your pc or laptop will do you just fine, so don't run out and buy anything..

Have a little patience and just let it charge.. The battery on these things last 10 hours, they won't charge back up fully in 20 minutes, though we all wish they could... lol
 
DontUnderstandMyIpad said:
Have you connected the USB cable to a pc/laptop?

The iPad draws a current of 10A and only the iPad wall charger supplies this current. A pc USB supplies a much lower current and will thus only trickle-charge the iPad.

I hope it's not drawing 10A.... :-). The battery would last only a few seconds if that.

For the OP,

USB only puts out around 5 watts and 1amp. That is why the iPad charges much slower connected to a PC/laptop vise the supplied 10 watt 2 amp power block.
Double check your USB specs... it is my understanding USB 2.0 is limited to 500 milliamps (0.5 amps). USB 3.0 is 900 milliamps (0.9 amps).
 
DontUnderstandMyIpad said:
Have you connected the USB cable to a pc/laptop?

The iPad draws a current of 10A and only the iPad wall charger supplies this current. A pc USB supplies a much lower current and will thus only trickle-charge the iPad.

I hope it's not drawing 10A.... :-). The battery would last only a few seconds if that.

For the OP,

USB only puts out around 5 watts and 1amp. That is why the iPad charges much slower connected to a PC/laptop vise the supplied 10 watt 2 amp power block.
Double check your USB specs... it is my understanding USB 2.0 is limited to 500 milliamps (0.5 amps). USB 3.0 is 900 milliamps (0.9 amps).

Actual current flow varies with the charge level required. If charge is really low, then the demand current wise is higher. As the charge reaches full, the current tapers off so as to not over charge. That is the regulators job. I know too much detail.
 
madhatter61 said:
Double check your USB specs... it is my understanding USB 2.0 is limited to 500 milliamps (0.5 amps). USB 3.0 is 900 milliamps (0.9 amps).

No need to double check my specs. I already knew them as stated. Maybe you would have preferred "up to 1A".

The only point worth taking away is something that has the capability to charge at 2A will charge the same battery faster than something capped at .5 or even 1A etc.

Cheers
 
Just use the 10 watt charger it came with

You can buy another if you need it from guess where? your iPod or iPhone or USB port do not put out 10 watts, only the iPad charger does.
 
Some USB ports put out a different amount of current (mA)
The USB ports on my desktop monitor put out very little power. Most USB hubs have a power supply with them and they put out more power, but I don't know if enough to make the iPad show that it is actually charging. I have a USB hub so I will try it later and let you know.

If you read up on the specs of USB 2.0 you will find the max current is 500 milliamps ... that's 0.5 amps. USB 3.0 is expecting up to 900 milliamps.

The Apple charger puts out 1 amp ... at 10 volts that would be 10 watts.
Or if limited to 5 volts it would take 2 amps to equal 10 watts. Standard USB chargers won't charge your battery.
 

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