I don't think you read my link. It discusses an *apparent* proprietary
signaling system in 12V/USB chargers that iPads recognize and Androids
do not. A high current charging device such as an iPad or Android
tablet needs to be aware of the USB connection and, if it's attached to
a computer, throttle itself back to the maximum current draw specified
for a USB port on a computer (0.5 amp IIRC). However, if the charger is
simply a USB connector connected to a 12V outlet in a car then the
device can safely draw 2 amps or more. Certain of these 12V chargers
will rapidly charge an iPad since the iPad somehow knows there's a high
current capacity automobile on the other side of the USB connector. The
Androids typically do not since they don't understand whatever the iPad
is doing to realize it's charging from a car rather than your laptop.
The recommended charger in the link is one that does allow an Android to
draw 2 amps for charging... depending on which of the 2 USB sockets it's
connected to.
There's a lot of detailed engineering study in that link.
Chuck Norcutt
On 1/4/2013 3:57 AM, Chris Barker wrote:
> iPads need more oomph as well. However, although it will say "Not Charging"
> when connected to a small current, it will do so albeit rather slowly.
>
> Chris
>
> On 4 Jan 2013, at 01:37, Chuck Norcutt <chucknorcutt@xxxxxxxxxxxxxxxx> wrote:
>
>> It's probably OK for phones but if you're trying to charge an Android
>> tablet what works for an iPad may not work for an Android tablet despite
>> what the specs say.
>>
>> Based on a reviewer's comments I just bought one of these which does
>> work on my Google Nexus 7
>> <http://www.amazon.com/PowerGen-Dual-Heavy-Ouput-Charger/dp/B00622AG6S/ref=cm_cr_pr_product_top>
>>
>> But if you have an Android tablet you might want to read the first
>> review of this device here by K Crawford. Lots of USB charging device
>> cautions for Android owners:
>> <http://www.amazon.com/PowerGen-Dual-Heavy-Ouput-Charger/product-reviews/B00622AG6S/ref=dp_top_cm_cr_acr_txt?ie=UTF8&showViewpoints=1>
>>
>> Chuck Norcutt
>
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