All hail to the USB charger

by Volker Weber

Every new gadget comes with its own charger. Often they have exactly the same specs (5V, 500 mA) but their own plug, so you have to carry a lot of them while travelling. There is no technical reason for this nonsense. Starting today, all devices which charge over mini-USB get a special nod. The same goes for all devices which can directly charge through a standard USB-port.


You only need to carry two chargers and one cable if all your gadgets follow this scheme: One universal charger which plugs into 100-250 V 50-60 Hz, one charger that plugs into 12 V terminals and cigarette lighters in your car, and one USB-to-mini-USB cable. If you happen to travel with a notebook, you often don't even need the chargers.

Of the two navigators I am currently looking at, only the Navman iCN 530 connects and charges over a USB cable and it wants exactly the mini-USB plug pictured above. As do the Blackberry 7290, the Blackberry 8700. The iPod Nano 1GB and the iPod 60 GB also charge through USB, but they need their own cable. The Nikon D70 connects through the standard cable, but it does not charge its battery. The Motorola RAZR uses a USB cable but wants to talk to its own power supply (or a Mac, or a PC with installed drivers).

Connecting through USB, but not charging over this connection can be especially bad, as the TomTom 910 has shown last night. It was fully charged when I hooked it up, I removed the MP3 tracks the last reviewer had left behind, but then I forgot to unplug it and went away. As it turned out today, the TomTom was running off its battery, which died somewhere through the night, rendering the device into a boat anchor. I connected it to its proprietary charger, let it sit there for three hours but it would still not turn on. I tried a dozen times to reset it, but it would not boot. Then I must have done something different and it woke up. So now it is connected through USB and its own charger. BTW: After only a few days I seem to be number one on Google for "how to reset TomTom 910" with my First Impressions post. I think I need to take a picture and turn this into a real How-To.


I've been taking the same approach for a long time, however it seems that the manufacturers really don't want to standardise. My guess is that a large portion of their profits come from selling the ludicrously overpriced cables rather than the item itself. There really is no reason why an iPod cable should cost GBP15 or a Nokia phone charger more than 10 pounds.

Completely agree that it's crazy for the TomTom to require a separate charging cable as well, it's not like it needs more power than can be provided over USB to run, just lazy design I think.


Matt White, 2006-07-15

My experience with USB connectors and charging is that sometimes the device accepts only its "own" power supply and does not charge from another one.
This looks similar but is different from the issue that a device hooked up to a computer cannot be charged if required drivers are not present - i guess this because the device needs to tell the host the amount of power required (which may decide not to supply it).


Volker Juergensen, 2006-07-15

Right. I have one Samsung MP3 player which does not charge over a USB cable, although it uses the same plug to charge from it's own power supply.

I believe that the Motorola RAZR only charges from your PC after you have installed the drivers. If you connect it to a Mac, it will charge right away. You can use a RAZR power supply to charge a BlackBerry, but not the other way around. My guess is, that the RAZR indeed is not happy if it just receives 5 V on the USB interface. So it won't work in my "one charger for everything" setup.

Volker Weber, 2006-07-15

Volker, my RAZR V3i charges just fine at the USB port of a MacBook. It did so also with the PC I had at my old Job. So maybe they changed this detail in the transition from V3 to V3i?

Markus Weimer, 2006-07-15

I do not see a contradiction.

Volker Weber, 2006-07-15

In the original article you wrote "The Motorola RAZR uses a USB cable but wants to talk to its own power supply." For my RAZR, that is not true. I can use whichever USB Power source I want.

Markus Weimer, 2006-07-15

My RAZR also charges by USB, but, as you wrote in one of the comments, only when the drivers are installed (at least under Windows XP). And my replacement for the RAZR, a Hagenuk S200 (aka Explore M68) also charges using USB, but needs its own cable (as does my Palm TX).

Dirk Steins, 2006-07-15

I've never been able to get my Blackberry 8700 to charge properly over USB from a macbook pro. It works fine from the Blackberry USB power supply. Anyone else seen this happen?

Andy Mell, 2006-07-15

@Andy - in our environment (7230, 7290, 7100, 7130 and 8700s), we have had to install the Blackberry device driver to allow charging through USB. I don't think there is such a driver for the Mac so you may be out of luck.

Colin Williams, 2006-07-16

7290, 8700 and RAZR charge on my iBook without any additional software. Cannot test the MacBook since I returned it already.

Volker Weber, 2006-07-16

The Audiovox SMT 5600 also has a Mini-USB connector, but will only charge if connected to a computer or an original power supply. Even worse, it sometimes won't charge when connected to the computer if it doesn't like the particular cable, for some reason. To top it all off, hardly any stores actually carry this phone, or its magical power supplies. I was in Manhattan and forgot my power supply at home. I urgently needed one and had to call around to about a dozen stores to find one - in MANHATTAN. Thanks, Audiovox!

Jeff Chausse, 2006-07-16

What about devices that require more power than the typical USB outlet provides? (There are already quite a few external HDD cases that may or may not destroy your mainboard's USB power supply...)

Oh, and did I mention that I want a standard gadget battery?

Hanno Müller, 2006-07-17

Charging via the USB plug requires a properly installed and working driver set for the corresponding device, since avery sane USB implementation will not leave the port power switched on when no supported device is attached.

Nevertheless, USB charging gets a double thumbs-up from me, as it is the most intelligent solution out there at the moment.

Karsten W. Rohrbach, 2006-07-17

This usb -> iPod adapter line is nice, and shrinks what you need to bring considerably:

Kevan Emmott, 2006-07-17

@vowe, with respect to charging blackberry using USB on the Mac, my Al G4 PB 15" doesnt charge it either, neither does the 17" Al G4. The charge light and symbol comes on on the blackberry, and it looks like it is charging, but the Mac isnt delivering enough juice, even after 4, 5 hours connected. Blackberry battery runs out again quickly.

On the D70, it is a pain to remember to disconnect this as soon as you have downloaded the pics because if you leave it connected it runs the camera battery down really fast!

Andy Mell, 2006-07-17

Holux PPS mouse: USB power. RAZR V3: USB power. RAZR does not feed on Holux´s charger. Sad.

Armin Roth, 2006-07-18

Note that the RAZR also needs to be turned-on to charge over the computer's USB port.

Mitch Wolfson, 2006-07-20

I have just discovered that the Blackberry does charge via USB on the Mac (Intel and G4) if, and only if, you install the PocketMac Blackberry sync software (available via free download from RIM) on the Mac. It seems that the PocketMac software has the required USB device drivers to allow USB charging! You can also get it from

Andy Mell, 2006-08-08


I recently ordered a travel charger for my Creative Zen extra. This arrived satisfactory and therefore proceeded to plug it in and charge my mp3 player. The green light comes on the charger but when I came back to the unit 8 hrs later and turned on my mp3 player it had not charged. I have since charged it using my PC via the usb and this works fine. So I then used it until it was empty then tried your charger again but the same thing happened green light on but nothing happened after i returned from work.

Do you thing the charger is faulty or is there an alternative solution?

Phil Marsh, 2006-08-13

Hi, I have read through your comments and the comments of visitors, but I am still not clear on what I want to do. (I am an ancient old bloke who knows nothing very much). My question is simple. I have a Tomtom One with a Tomtom USB charger. I am not too worried about carrying maker's cables with me, but I would like to charge my iPod Classic 80Gb from the Tomtom USB charger without risk of damage to either. Common sense tells me that the USB voltages and pin locations will be to a common standard and that the device (i.e. iPod) will only pull the current it needs upto the limit of the charger. Are you able to confirm that I am correct and that I can carry just the one USB charger for both devices?

Richard Diebel, 2008-02-29

The U in USB stands for universal. You will be fine.

One option is to look at the Powermonkey Explorer which is an excellent pack of charging options for travellers.

Ben Rose, 2008-02-29

Razr requires a special pinout that can be found at

Ben Malle, 2008-06-21

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