Today, a 5 min USB powered desk lamp. I had problems with the neon lights at work so I decided to build a quick and easy LED desk lamp that is powered by the USB port in my desktop PC.
Step 1: You Need?!
1. A 1-3W LED on a star IMS, means insulated metal substrate, basically a piece of Aluminium + a PCB.
2. A lampshade, referring to the genius Jim Jarmusch, see here.
3. Some enamelled wire from an transformator, possibly some of the secondary coil, cause of the thickness. It has to be rigit enough to keep up the lampshade + the led (with PCB)
4. a small piece of plexiglss, 1mm thick 11mm x 30mm.
5. El. drill, soldering iron, 2 diodes...
I bought my tiny lampshade + LED @ Satisled.com , which I think is a pretty good an convienent shop (in China) - but well you know, that's just like, my opinion, man...
Step 2: Things to Do, Part I
Cut off the desired lenght fo the enamelled wire, about 1,5-2m - Yes, we have got the metric system :-)
Put both ends into drill's chuck and thighten it. Wrap the looped end of the wire around something like a tube or an vice.
Now put tension to the wire, by pulling the drill and start winding the wire. See pics. You can easly make speaker wires like that...
Step 3: Part II
Drill two holes Ø2,5mm into the reflector / lampshade. Put one end of the wire thru both holes, so that you can solder the LED, centered in the middle of the reflector. Again see pics.
To reduce the LED Voltage you need to put two diodes in series to the LED. You don't really have to care about the current, USB ports can do max 500mA, a 3W LED can easily be driven with that :-)
Step 4: Part III
The USB Plug!
Same procedure as last step. Two holes, wire thru. Strip 7mm of the wire. Now you have to position the two wires with a distance of 7mm, possibly centered on the piece of plexiglass or whatever plastic you may find (maybe from an plastic bottle).
Apply some heat onto the contacts, so they can sink into the piece of plastic.
Please check the polarity of the Plug! You can see the USB config on the pic above.
Bend the "remaining" wire so that you can place the lamp onto your desk and plug in the USB the same time...
Step 5: Done!
Took 5-10 min!
Would be very amused to see yours ;-)