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Droid charge through USB

So, Im returning/exchanging my droid for numerous battery issues. One of which i want to confirm. Is the Droid supposed to charge through the USB to computer connector? The device stays at the same level of charge but does not increase when its plugged into my computer.


the droid appears to follow the USB spec (unlike MANY other devices) and it first connects to a usb port at only ~100 mA (which might barely charge faster than it uses power). Then it ASKS the host device for permission to use more power. I think it steps to 300 or 500 mA IF the host device says it's OK. If the host device doesn't reply that it's OK then the droid will not draw more power.

if the laptop feels it doesn't have power to spare it will tell the droid to stay at 100 or only step to 300.

for comparison the stand alone wall wart supposedly outputs 850 mA.

when hooked up to a 3000 mA charger so it can suck it's max, the droid seems to pull something like ~1500 mA
 
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the droid appears to follow the USB spec (unlike MANY other devices) and it first connects to a usb port at only ~100 mA (which might barely charge faster than it uses power). Then it ASKS the host device for permission to use more power. I think it steps to 300 or 500 mA IF the host device says it's OK. If the host device doesn't reply that it's OK then the droid will not draw more power.

if the laptop feels it doesn't have power to spare it will tell the droid to stay at 100 or only step to 300.

for comparison the stand alone wall wart supposedly outputs 850 mA.

when hooked up to a 3000 mA charger so it can suck it's max, the droid seems to pull something like ~1500 mA


I have a usb car charger that says 5V, 1000mA. Will not charge my Droid but charges my bluetooth headset.
 
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I ended up getting a secondary USB to MicroUSB to use in the car. Bought one of those Griffin USB cigarette lighter adapters. Comes with 2 ports so I can plug in my TomTom and phone at same time if need be. (Just have to find a USB to MiniUSB that will fit in the slot for my TomTom as it's got a weird body shape and a straight up plug won't seem to do the job.
 
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I can charge via usb to my desktop or laptop, but it's much slower than when plugged into a wall socket. I have an inverter in the car with a 1000Ma rated usb port. It doesn't charge my droid, but it does charge some of my other devices. Using the a/c plug on the inverter does charge my droid.
 
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My experience is that Motorola devices will sometimes not charge using a non-Motorola charger. On the other hand, everything seems to charge with a Motorola charger (bluetooth, Garmin, etc.).
I've noticed this as well. I used a motorola mini-USB wall charger to charge my BlackBerry with no problems. When I lost that charger, I got one from RIM. I tried to charge my Motorola S9 bluetooth headphones with it, and it wouldn't charge.

I can however, charge my Droid with a generic micro-USB charger and the charger that came with my friend's Palm Pre.

But to get back on topic, yes USB is slow to charge. It took about 4 hours to get a full charge from 70%.
 
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the droid appears to follow the USB spec (unlike MANY other devices) and it first connects to a usb port at only ~100 mA (which might barely charge faster than it uses power). Then it ASKS the host device for permission to use more power. I think it steps to 300 or 500 mA IF the host device says it's OK. If the host device doesn't reply that it's OK then the droid will not draw more power.

if the laptop feels it doesn't have power to spare it will tell the droid to stay at 100 or only step to 300.

for comparison the stand alone wall wart supposedly outputs 850 mA.

when hooked up to a 3000 mA charger so it can suck it's max, the droid seems to pull something like ~1500 mA
do you know if there is a way to reconfigure device driver to supply more power? if possible, is it OS dependent?
 
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No, there is not. It is USB specifications to supply only 500 mA, and many modern systems will detect an overvolting of the port as a short and the PSU may eithre shut down or the motherboard may shut down to prevent any problems.

However, if you get an AC --> USB adapter like the one that came with your phone, I ahve seen those go as high as 1000 mA, thereby allowing a faster charge of the DROID.
 
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My experience is that Motorola devices will sometimes not charge using a non-Motorola charger. On the other hand, everything seems to charge with a Motorola charger (bluetooth, Garmin, etc.).

Here's whats going on. USB power is on pins 1 and 4. Data is on pins 2 and 3. A simple AC charger has pins 2 and 3 shorted together. This tells the phone that is an AC charger and to charge at a higher rate. If you are using a USB car charger and its not charging fast enough, you ned to modify it or get on that has pins 2 and 3 connected. The easy way to tell is to look at the battery stats on the phone. It will either say Charging USB or Charging AC. If it says USB its going to be charging at a slow rate.

I opened up my USB car charger and wired 2 and 3 together and it now charges great. Some USB devices care, some dont. The Incredible needs pins 2 and 3 connected. Some iPods want 2 volts on pins 2 and 3 to make them charge. Other devices dont care.
 
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Hello there. I've read somewhere that a laptop can still charge a usb device, in my case an Android phone, even when the laptop is off but connected to a wall socket. Anyone heard about it or even tried it ? As for charging time it takes around 4 hours to fully charge my Samsung GTI5500 but then the battery doesn't last as long as if it was charged with the adaptor.
 
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If you are using a USB car charger and its not charging fast enough, you ned to modify it or get on that has pins 2 and 3 connected. The easy way to tell is to look at the battery stats on the phone. It will either say Charging USB or Charging AC. If it says USB its going to be charging at a slow rate.
You're still limited by whatever current the charger can provide. USB maxes out at 500mA (USB3 is higher). Check the specs on your charger. The more current, the faster the charge. My car charger supplies 950mA, for example.

Hello there. I've read somewhere that a laptop can still charge a usb device, in my case an Android phone, even when the laptop is off but connected to a wall socket.
Depends on the laptop. Mine do not provide power to the USB ports when shut down. As stated above, USB is limited to 500mA so I don't use it to charge for that reason.
 
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My Casio Commando doesn't seem to be charging via the USB port on my laptop either. The red light doesn't come on, nor do I see the battery icon on the top of the screen indicate that the battery is charging. I do have the USB selected to "Charge Only". When I first plugged my phone and cable in to the USB port, I got a message on the laptop that a new device had been plugged in, but could not be installed. Any help would be appreciated. Thank you.
 
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