OK, this may be a dumb question but I can’t seem to find the answer.
I have several devices that can be charged via USB cable (my cell phone and my iPod, for example). All of them have power bricks chargers with what looks like a USB cable coming out of them.
Are all of these chargers the same? I’m traveling next week and am trying to decide if I need to carry separate chargers for everything or if I can get by just carrying one. (I know I can always charge everything by plugging them into the USB port on my laptop, but I’d rather not leave my laptop running all the time just to charge everything.) TIA.
Are you talking about those little wall-warts that just have a USB socket, that are supplied with a charging cable that can either fit in there, or be used to charge from any normal USB socket in a computer?
If so, yes, they should be the same - USB is a well-defined standard in terms of voltages, maximum current, etc. I suppose it’s possible that some manufacturers just liked USB connectors so much they decided to use them for something non-standard, but I’ve not encountered such a thing.
Yeah, that’s what I’m talking about. I have a wall adapter that has a USB cable socket on it. (It’s the one for my iPod, actually.) I plug the same USB cable into it that I plug into my computer’s USB socket; it doesn’t even have a cable of its own.
The reason I’m asking is that when I got my new cell phone I asked if I could use that same adapter and the sales drone insisted that it wouldn’t work, even though the phone can also be charged by connecting it to my computer with a USB cable. (The phone came packaged with its own charger so it wasn’t a case of them trying to sell me something else. The charger cable is attached but it just plugs into the same USB port on the phone.)
I couldn’t imagine why something that can be charged via a USB port (which I know is a standard) couldn’t be charged by any equivalent device but since this person was insisting otherwise I thought I should ask somewhere that I knew I could get an accurate answer.
(Edit: Sentences make more sense when you include all the words. :smack: )
It really should. I suppose it’s possible that a manufacturer could have made a bunch of wall-warts that are only rated for the current their device requires, rather than the USB standard, but it seems unlikely - in fact, I’m pretty sure the wall-wart part of the device is a generic part now, bought in bulk, rather than manufactured by the same company that makes the phone or other device.
I expect the sales drone was either simply wrong, or was saying that because of a company policy of erring substantially on the side of not recommending anything unusual or potentially warranty-voiding.
Ah, that was probably it. They didn’t want me to go off and plug it into something weird then come back with a fried unit saying “but they said it was OK!”
Thanks, that matches what I was thinking then. I just wanted to make sure there wasn’t something I was missing before I plugged something in. Thanks for the help.
My wifes Krazor (Motorola cell phone) can be charged with a usb cable attached to the computer, My Razor has the same connection but will not charge using the usb cable connected to the computer.
I would say there is a difference.
A “Wall Wart” charges either one :dubious:
There are some differences. I have a Motorola charger that charges the battery faster than the Motorola charger that was supplied with the cell phone. They look the same but have different part numbers and current sourcing capabilities. Both use the mini-USB connector.
For some reason, the Motorola phones don’t charge the same as other devices. When a friend got his, he noticed that it wouldn’t charge from the USB on his laptop until he installed the Motorola drivers; after that, it worked fine. The same thing might apply to USB power supplies.
In my own (non-Motorola) experience, not all USB power supplies will charge my iPods. However, my iPod power supplies have charged any and all of my other USB devices - GPS, Treo, little USB battery (that one rocks, btw), etc.
I’d second the not all are equal statement. My motorola won’t charge from the same charger that my pocket pc charges from. My pocket pc won’t charge from the car adapter that the motorola works from. The motorola wont charge from usb at all.
My GPS (Garmin) and phone (Motorola) both take USB chargers. But if I try to plug the Garmin into the phone charger, it thinks I’m plugging it into a computer.
[ul]
[li]If you have two wall warts with different current capacities, the warts are not interchangeable. But you might be able to use the larger-capacity wart to charge either device, as long as the output voltages are the same (should be 5V).[/li][li]It is possible that a high-current wart might produce somewhat higher voltage than what its label states, if its designers assumed that the charge current would load down the voltage to 5V. This might present an overvoltage if you connect a lower-current device. I rather doubt it. Alas, it might be difficult to measure the actual voltage with a device attached.[/li][li]In any case, I think a device that charges off of a USB port should charge equally well off a 500mA USB-style wart.[/li][li]If a wart with enough current capacity won’t charge a device, then perhaps the device-specific wart actually implements some sort of USB master. This seems like an odd thing to do, but I guess it’s possible. This might explain some of the behaviors described upthread.[/li][li]Re charging from the PC, in my experience, some PC’s won’t apply power to a USB port if they can’t identify the device and hook it up to a driver.[/li][li]Each device requests a certain amount of current from the computer’s USB port. Even if the device has a driver, the bus master might not give it power if other devices are present and adding one would exceed the 500mA/port limit.[/li][/ul]
I hope this helps. It has been a while since I was steeped in USB, so YMMV.
I have an HTC blackberry-type thingy that has a dedicated USB charger.
I have noticed that it charges much more rapidly from this than when plugged in to either the desktop or laptop computers, which leads me to believe that the current from the dedicated charger is higher than from the computer USB connection.
My Motorola rapid charger can supply 850 mA at 5 V, which is substantially more than what a standard USB port provides. Some PCs will not charge the phone if they do not have a device driver for the phone. With some systems it’s included in the base operating system, with others, you need to get a driver from the cell phone’s manufacturer. Motorola has a connectivity kit that you can get fairly cheaply on eBay from many dealers.
OK folks, I have come up with a solution that works and thought some of you may be interested.
The problem is that I have several devices all of which can be charged through a USB cable. I am heading out on vacation and am trying to reduce the amount of cord clutter, so I didn’t want to have to carry four or five power bricks around with me.
I can charge all of these devices from my laptop but didn’t want to have to leave the laptop on and running all night just to charge my iPod and phone.
What I discovered is that I can use a portable, four-port, powered USB hub as a charger. I just take the hub and its power cord and plug it in. Then I plug all the devices into the hub via their cables.
The hub isn’t connected to a computer but that doesn’t seem to matter. And things may not charge as fast as via a dedicated charger, but I wanted this for overnight anyway. And this has the advantage that I can charge multiple devices at once.
So this seems to have solved my problem, though I do find it interesting that what looks like a standard USB cord may not really be standard. Thanks everyone.