How to make it work? USB + 5V rechargeable battery + 12V LED strip!

I want to an LED Strip that works my USB or Battery, I got the battery and the USB working fine, the battery charges up without problems, but I need to light the LED Strip (12V) with a 5V battery.
Is there a DIY way to:
-Step up the voltage, or
-Step down the LED Strip Voltage.

I know each SMD LED works around 3V, but I can't make sense of the wiring and resistors on the Strip, to wire the SMDs in parallel.

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DavidN712 years ago

eBay is your friend. USB 5v to 12v step up module for less than $5 shipped from China. Check your current requirements before ordering.

http://www.ebay.com/itm/USB-DC-5V-to-12V-DC-DC-Boost-Converter-Step-Up-Module-for-Monitor-Camera-LED-DVR-/281422102373?pt=LH_DefaultDomain_0&hash=item4186107f65

Engineering answer: boost convertor

GarrettH22 years ago

I've never tried this before, but I don't see why it wouldn't work:

1. 2 voltage doublers in series (since this is all DC, you'd need an H bridge + oscillator to simulate an AC input for the doublers). This will give you 20VDC output.

2. Regulate the 20V down to 12V with a simple DC regulator circuit.

It would probably be simpler to buy or make a 5V LED strip though. :)

Doulos32 years ago

I just did some preliminary research and if you don't want to tear apart your led strips (what's the point of them then?), then from what I've seen a SEPIC Buck Boost converter might do the trick.

This guy on youtube reviewed one he found on ebay and it seemed to work pretty well. I think he said it was made for solar panels and their charging devices. Just make sure you know how much current your LED strips will be pulling, so that you don't burn the circuit out (Although USB 3.0 can only really deliver at most 4.5 W or 900 mA at 5 V, even though I think it might eventually go as high as 100 W). I'd also bet you could find the pinouts for USBs somewhere on this website.

The LEDs are set up is sets of 4 LEDs. Each set is wired in parallel. In order to make it work on 5V you'll need to remove all the LEDs and get new resistors. Check an LED calc for the best arraignment.