I know there are other instructables about USB flashlights. I got the idea reading this one when I saw how similar the circuits were. This is the only solar and USB one I know of though. I do not want anyone thinking I copied this idea.
DISCLAIMER: I AM NOT RESPONSIBLE IF YOU FRY YOUR LED LIGHTS, YOUR USB PORT, SET YOURSELF ON FIRE OR KILL YOURSELF (SOMEHOW). WHAT YOU O WITH THIS INFO IS NOT MY FAULT. YOU HAVE BEEN WARNED.
Step 1: Materials
- One solar LED flashlight (these are widely available for about $1 on ebay. This is where mine came from)
- Male A USB cable (these can be cut from almost and USB cable)
-two resistors (1/4 watt), my LED light's battery was rated at 3.6v, so a 3 K ohm and a 4k ohm would probably be ideal. I could not find these so I substituted. My resistors only gave me 3 volts, and now my LEDs are dim when USB charged
-misc.: wire, solder, soldering iron, pliers, wire cutters, side cutters, dremel (optional), shrink wrap (optional, but recommended), and other hand tools may come in handy
Step 2: Take It Apart
Step 3: Electronics...
Note: shrink wrap will prevent shorts and is recommended
Step 4: Case Work
Step 5: Snap Together
Step 6: Testing and Improvments
-do not push the botton when it is plugged in. The LEDs will probably fry.
-there is no mechanism to prevent overcharge. Do not leave this plugged in unattended for more than a few minutes. If it is hot unplug it. If it creates fire unplug it and put out the fire.
- use the right resistors (so it is not dim)
-replace the battery with some super-caps
Hope you enjoyed this instructable