USB Charging

[gwalborn]

I have found the Backflip to be VERY choosy about what USB ports will or will not charge the device. For example, it (thankfully) charges using the 110v adapter that comes with the phone and it charges just fine from the USB hub on my computer, but it refuses to charge from one of my cigarette lighter-to-usb adapters and refuses to charge from one of my iPhone USB chargers. Has anybody identified the determining factor of what USB ports will charge and which USB ports will NOT charge the device? Who is not following the standard here, Motorola or the USB charger manufacturer?

gwalborn

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[TechN9ne1730]

This sounds really strange. So long as the USB port is powered, which I believe all USB ports are unlike e-SATA ports, then it shouldnt matter, but unless theres a fluke in your testing then it sounds like motorola is at faukt.

[gregh2000]

Nokia phones do that too. There needs to be some sort of a resistor on the data lines or something on the other end of the cord. Those cig power to usb things are just dumb power and don't put the info on the data lines needed to kick the phone into charge mode.

[Spooky Electric]

I know my old iPhone car charger had different voltage specs, so I think that might be a factor (think this phone uses a higher voltage rating). I know other people said their old blackberry (can't remember what version) chargers worked. I have noticed that my phone charges VERY VERY VERY slowly when plugged into a USB port. Also on my laptop, i have a couple USB ports that have a lighting bolt next to them, meaning that they are "powered" USB while the others are not, and it seems to charge faster when plugged into the powered ones. Also if you use a non powered usb hub and have other devices plugged in, it'll effect how well your phone will charge.

I know some people have noticed that if you let your phone die, then plug the phone into your computer, they said their phone won't charge at all. My phone died while I was at work, and I didn't have my wall charger, and after about 20 minutes of it being plugged into my non-powered usb hub, (computer under desk and didn't feel like having my phone on the ground charging with its short cord) the phone randomly came on with its charge battery symbol and I was able to turn it on. Next time I'll let it die and plug it directly into the computer and see if that changes anything.

[jmgib]

Correct me if I'm wrong, but I thought all USB ports were powered?

[dchandler]

The same is with car chargers, I have a car charger for my blackberry and tried to charge me backflip, It said it was charging but it didnt

[Spooky Electric]

Correct me if I'm wrong, but I thought all USB ports were powered?

That is correct. But on laptops some of them are low powered and some are higher powered. We had a usb powered desk scanner that wouldn't turn on till it got plugged into the higher voltage usb port on my laptop, wouldn't work on my non powered usb hub either. Don't think this is true on desktops. Now I haven't done much research on this so don't quote me and all usb ports could have the same voltage specs. Not to sure. Something for me to look up when I have the time.

[vasekvi]

I sell mobile phones and accessories at Fry's Electronics, and I can vouch for the variations in charger compatibility, even though they are all MicroUSB and are supposed to work the same. There is some off brand from China that I tried just yesterday that is a 110V AC charger and the dumb thing only charged like 1 percent every 5 minutes or so. The charger that came with the phone charges the phone pretty quickly, especially compared to that. In an extreme case of incompatibility, I noticed that the Cellet brand MicroUSB AC charger not only charged the phone slowly, but made the touchscreen coordinates flip out as well. I could not even unlock my screen with the unlock pattern unless I unplugged the phone from the charging cord. I highly recommend the Fast Rate MicroUSB charger made by Motorola to charge your Backflip in the car. If anyone is in the Atlanta area and wants to get one, I will let you have my discount. Marks it down from 20 bucks to less than 7.

This is the charger I can assure you will charge your phone properly in the car.

[jmgib]

I think those chargers are like $30 online from Motorola.

[gregh2000]

From my understanding with USB charging is that the USB ports put out a lower amperage until they negotiate with the USB host then flip to full power. Like it has to tell it hey I need amperage then it provides it. I am guessing with the dumb chargers it doesn't work. Like my BlackBerry 9700 would not charge off my usb to cig power in the car but my iphone juice pack would. I also can't get the blackberry to charge off the ports on the side of my monitor but it charges on the computer just fine. Other stuff charges on the monitor like my headset or juicepack. Seems some devices need that data connection first.