Thanks! for posting this valuable information. I have been mystified by batteries in
general for a long time... the older I get, the more I don't understand. I have
always presumed there is the "Apple way" and perhaps several other models of the
universe, so I am not at all surprised by the fact that devices intended for use with
Apple products are the spawn of the devil and may not work in non-Apple situations. I
look forward to more revelations - especially about battery monitoring apps.



On 1/31/2014 7:37 AM, Danny D'Amico wrote:
On Fri, 31 Jan 2014 06:53:54 +0000, Danny D. wrote:

Today I hurled enough invectives at my Samsung Galaxy S3 to make a whore
blush, simply because the GPS wouldn't work under power.

Here's a summary of what I've found out, in bits and pieces:

STUFF I KNEW FROM PRINTING ON THE PHONE & BATTERY:
- The Samsung Galaxy S3 itself, is rated at 3.8V, 1025mA.
- The Samsung Galaxy S3 battery is 3.8V, 7.98Wh, 2100mAh, Li-ion.

STUFF I LEARNED SO FAR:
Note: *** indicates important but unproven statements found on the web.
- The 2100mAh battery can be charged at up to 2.1 Amps (1x Capacity).
- We're told the S3 never allows more than 800 to 900mA of charge current.***
- We're told the S3 does not trickle charge after 100% capacity.***
- Settings-More-About Device-Status-reveals the charge assumption.
- If the S3 sees 2 data pins shorted, it assumes "Charging (AC)".
- If the S3 does not see shorted data pins, it assumes "Charging (USB)".
- Cables can be either "data" or "charging" (with shorted data pins).
- Charging (USB) will be limited to 500mA current draw.
- Charging (AC) is not known to be limited in current draw.
- The stock S3 AC charger is 1A.
- We're told Apple-spec USB chargers put voltage on the data lines.
- So, the S3 will assume "Charging (USB)" with a normal "data cable".
- A "charging cable" switches the S3 to "Charging (AC)" on Apple USB.

CRITICAL FACTORS (the Samsung Galaxy S3 "charge assumption"):
- An S3 assumes "Charging (USB)" with PC USB & a "data cable".
- An S3 assumes "Charging (USB)" with Apple USB & a "data cable".
- An S3 assumes "Charging (AC)" with wall chargers & a "data cable".
- An S3 assumes "Charging (AC)" whenever a "charging cable" is used.

OPEN QUESTIONS:
- I still don't know how to tell how much current is actually drawn.
- None of the Android battery apps I tried gave current draw in amps.
- Instead, they listed charge in cryptic terms such as "12%/h".