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What do I need to do in order to power an LED light strip via USB? Answered

I would like to purchase some bulk led light strips (like http://amzn.to/xL9pka) to create bias lighting behind my monitor and near my keyboard.  Since USB ports are nearby, it would help keep the wiring cleaner if I could leverage them.  I don't want to power the entire strip, just a short segment.  I could buy this connector http://amzn.to/wxOqSO to attach to the strip, but I'm not sure how (or if) I could connect the wires to a USB connector.  How can I accomplish this?

I would like to end up with something similar to the Antec Halo Kit.



If you must run from the USB 5V, you need a circuit to step the voltage up to 12V. This could be done with an MC34063; those are the 8 pin switching regulators found in nearly every car cellphone charger and car USB adapter. Figuring out how to make them step up instead of down is left up to you, but the data sheet and application notes for that chip it should help.
There's some links to documents here:

The more sensible solution might be to install an eSATA connector on the case, since that will come with a power connector as well.. Or use a 12V wall-wart; they're commonly used for PC speakers, scanners, and 3.5" external hard drives. If there isn't one in a nest of wires in your closet, try a thrift store, yard sale, or order one direct from China on eBay.

Kudos to you my friend, I never would have thought of finding a switching step-up/down regulator in a car charger :) Just saved me a ton of time on a project!

Those are 12V, whereas a USB port will only supply 5V. With that many LEDs, the USB port may not be able to supply sufficient current.

You can get short lengths of lower voltage 3 or 5V strips, which can be powered from the USB using only a resistor, so would be better for this purpose.

I don' t want to power the entire strip, just a few inches worth. There should be cut points between every few leds. You could then attach something like this to the strip: http://www.amazon.com/gp/product/B0040FPHL8/ref=noref?ie=UTF8&s=hi&psc=1. Could I attache the other end of the connector to USB for powering the strip?

Those strips are still 12V, so cannot be run from a USB, even if you only use a short length.You need to find a lower voltage strip, although as iceng says it will probably be simpler to make your own.


6 years ago

If they are not a series of leds it is as simple as changing individual
resistors, otherwise one or two leds heave to be shorted out and the
resistor will have to be changed.. 
And that is harder then making your own led strip.


It states it require 12vdc. One end has a DC Jack.
Lower on the page they have a 12vdc Power Supply listed as well.