Make a Kindle USB Charger

Amazon’s concept for the Kindle is to divorce the reader from the PC. You don’t even have to own a computer to enjoy the Kindle because you can purchase and download all your books directly from Amazon without having to sync with a PC.

Great concept.

Except for charging the battery.

Amazon provides a wall wart power charger and a separate USB cable to connect to a computer. Unfortunately, the Kindle won’t charge from the USB cable. (I know the docs say it will “trickle charge” but come on, if I have to leave the thing off and connected to the USB for a couple of days to charge then it doesn’t charge from USB.)

I travel a lot, and the last thing I want to do is lug around yet another power cord to plug into the wall. All my devices charge from USB, that way I only have to carry a power cord for my notebook and everything else charges off of it. (Side note – Always take an extra AC power brick for your notebook when you travel. The one you have will die on you at the worst possible moment.) I also have a USB car charger that I use for the iPod, iPhone, GPS and other devices, so a USB charging cord for the Kindle would be nice.

Well no one seems to make one. That may be because of USB’s one amp current limit. The charger for the Kindle is rated for up to two amps, but when I put my amp meter on it, it never once went above one amp, so it may be that the two amp rating is overkill. It might also be that my battery wasn’t totally depleted and it doesn’t draw the full current on a mostly charged battery. If you make a USB charger for your Kindle, don’t blame me if it destroys your USB port. It works on mine, your mileage may vary.

To make a USB charger you’ll need an “A” power tip. I got mine at Radio Shack along with a pigtail to connect to the USB cable. I don’t remember the exact price but it wasn’t more than a few dollars.

Cut off the end of a spare USB cable, and strip the cover back. You’ll need the positive and negative wires. I’m going to be deliberately vague about that because if you don’t know enough to look up the USB pinout you shouldn’t be doing this. Connect the tip of the A plug to the +5v wire.

The end result looks like this:

If you enlarge the picture you can see the power LED lit up next to the power plug on the Kindle.

This cable is a little crude because I couldn’t find my heat gun when I was making it Sunday afternoon so I couldn’t use heat shrink tube like I wanted to. That’s why you see a few inches of cable between the plug and the electrical tape. As soon as I find my heat gun I’m going to cut that off and make it look better.

With this cable I can charge my Kindle from the notebook, a 12v car adapter or an iPod AC USB adapter.

UPDATE (4/4/09) The Kindle 2 comes with a USB cable and charges through the USB port.

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0 Responses to Make a Kindle USB Charger

  1. Pingback: kindle world » Blog Archive » New blog post: Make a Kindle USB Charger

  2. I heard that others are also using Samsung Travel Adapter model TAD077JBE, Input:120 VAC 60Hz 140 mA Output:5.0V ~ 1A as a charger.

    What can you say about that?

  3. alan says:

    The “A” tip the Kindle uses is an industry standard so there are probably a lot of charging devices out there that would work. As long as the output voltage is 5v and the current doesn’t exceed 2 amps then it should work with a Kindle.

  4. Bob in Bangkok says:

    I left my charger back in Miami….
    So, went to MBK…cell phone city in Bangkok. On a mission o get my wife’s Blackberry to boot(dropped twice in water, unsuccessful) and find a charger. !st shop I stopped at didn’t have one, but went down the row to a 2nd shop…now had a 1000 ma charger but a wrong plug(and a agent), now three of us went down the row to a 3rd shop, who had the righ plug/cable(now two agents)…”come back in 1/2 hour, we have for you…400 baht.” The $13 usd paid for the hardware, and two agents.

    Now have a working charger ! It does get hot, but not extremely so.

    A trick I learned when I had to replace a Dell charger here: if the charger trips on an overheat, put it in the freezer with the computer on top, outside! No problem!

  5. Dan in Key Largo says:

    Thank you for saving my vacation. I forgot the Kindle wall charger and was keeping it going with the USB trickle charge, but apparently it got a little too low and would not acknowledge the USB cable. A quick trip to Radio Shack, $11.50, and about 5 minutes with nail clippers & a band aid (as electrical tape) has me charging from my laptop. And now I can read when it is charging off the laptop, which I couldn’t do with the trickle charge. Thanks.

  6. Vince says:

    I did this and it worked great. Thanks for the tip.

  7. R says:

    Can any one comment on if the “A” type adapter is 3.5mm or 2.1mm or ?


  8. alan says:

    It’s 2.1 mm according to my ruler. I don’t have metric calipers.

  9. Pingback: DIY Kindle 1 USB Charger | Amazon Kindle and Kindle 2.0 Blog

  10. debbie says:

    can i use a blackberry charger to power a kindle 1?
    it seems to be the same size.
    I think the battery is drained to nothing…does that matter?

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  12. Pingback: DIY Kindle 1 USB Charger | Amazon Kindle, Kindle 2 And Kindle DX Blog « Vavcare Blog

  13. Pingback: DIY Kindle 1 USB Charger « Vavcare Blog

  14. david says:

    is there an adapter that can change the mail kindle into a male blackberry?
    so i can use the same usb wire for both devices with just a change of the adapter on the non usd end?