LED Desk Lamp Project

This is an LED driver called a Bucktoot made by LEDdynamics.  The neat part about this driver is its small size.  It's only 3/4" long!  The driver runs the LED with a constant current (350mA).  Because most electronics run with a constant voltage instead of constant current, it is much easier to get a constant voltage power supply.  The driver converts the constant voltage from the power supply into the constant current that the LED needs to run properly.

Here I've soldered the wires from the LED to the driver.  It's important to make sure the + and - connections are hooked up properly as the LED will not light up if you hook it up backwards.


By putting heat shrink tubing on the wires before soldering them, I can just slide the heat shrink over the solder joint and then heat it (I used a lighter) to make sure the wires don't touch and short out.  I like heat shrink tubing the best, but you can use electrical tape as well.  If using heat shrink, make sure to shove it a ways away from the wire ends before soldering or else the heat from the soldering iron will shrink it before you're ready.


Here's a cheap "wall-wart" type power supply I'm using.  It's rated for 12V at 200mA or 2.4Watts.  My LED will only be using around 1W, so this supply should be fine.  I've cut the end off because I don't have the mating connector handy.  I plugged it into the wall and used my multimeter to determine which wire was + and which was -.  I put some red electrical tape on the + wire so I could easily tell them apart.


Once I identified which wire from the power supply was +, I soldered the two wires to the input of the bucktoot driver.  Again, it's important to make sure the polarity is correct before applying power.  Hooking things up backwards could damage the power supply, driver, or LED.


Here is the completed electrical system.  The wallwart plugs into the wall and sends power to the bucktoot driver.  The driver converts that power to way the LED likes it, and then sends it on to the LED.  The next step is to hook it up and make sure it works!


Yay!  It works!  These LEDs are bright!  After waiting for the spots in my vision to go away, it's time to put the whole thing together.


Here are all the parts for my desk lamp.  I have the power supply, driver, and LED w/ heat sink from before.  Also in the picture are a block of wood with some mechanic's wire (a stiff but repositionable steel wire) screwed to it and some split-loom style tubing.


To attach the mechanics wire to the wooden base, I just bent the wire around the screw using my needle-nosed pliers and then screwed the screw into the base.  I added a washer to help pinch the wire against the wooden base and keep it from turning.


After drilling a couple of holes in the heatsink, I bent the mechanic's wire through the holes in such a way that it holds the heat sink.  It's a bit difficult to see in this picture, but the heatsink and LED are about 8" in the air over the base.  You can see the bucktoot driver hanging in the air from the wires.  We'll hide that in just a moment.


I've hidden the colored wires, the mechanic's wire and the driver inside the split-loom tubing.  My lamp is complete.


After plugging it in, I immediately start using the lamp.  It's awesome!  It's a lot brighter than my camera makes it look, and it makes it really easy to read those tiny numbers on electronic components or to identify resistor color bands.  My camera makes it look a little blue, but its actually a very nice white and it does a much better job with the resistor color bands than the overhead fluorescent lights I have in my lab.