Build a Bright, Low-Power Little Big Lamp This Weekend

Little Big Lamp was originally conceived and built in 2006 by MAKE Contributing Editor Charles Platt as a low-power alternative to incandescent bulbs, and wired to run on 12V for use in motor homes. Six years ago, when white LEDs were in their relative infancy, Charles’ project required 72 10mm LEDs, consuming 5W of power to produce the comparable amount of light as a 60W incandescent. These days, even greater brightness and spread of beam is possible, and the circuit has been updated to use 18 5mm LEDs.

This project is composed of three segments: the LED array, the simple circuit, and the lamp body. This is a good project to learn about wiring LEDs in series without resistors. The simple circuit, which combines the venerable 555 Timer with a Darlington array, will introduce you to the principle of Pulse Width Modulation. As for the lamp body, that’s where your maker chops come in! Charles used PVC components purchased from plumbing and hardware stores to build his minimalist desk lamp. You are free to follow this design, or customize your own to suit your space and needs. Some modifications that come to mind include a gooseneck, using clear plexi so all the wiring and components are visible, or rewiring the circuit to be battery powered for true portability. The possibilities are endless!

Sign up below for the Weekend Projects Newsletter to receive the projects before anybody else does, get tips, see other makers’ builds, and more.

More:
See all of the Weekend Projects posts

3 Responses to Build a Bright, Low-Power Little Big Lamp This Weekend

Elliott J. Olson on September 21st, 2012 at 1:12 pm said:

Why are you drilling the power and pot holes in the base AFTER installing the wires? It’s more chance of snagging or nicking wires that way. Otherwise, nice project.

Reply ↓
Erkko on September 22nd, 2012 at 4:01 am said:

” 5W of power to produce the comparable amount of light as a 60W incandescent”

It did not. Ordinary “white” 5mm or 10mm clear plastic LEDs produce less than 50 lm/W, typically between 30-40 these days, whereas incandescents produce roughly 13 lm/W which makes the lamp about 1/3 as powerful as the bulb they’re claiming to replace – at best.

The problem is in the plastic casing that doesn’t allow heat to escape, so the temperature at the junction rises and the light output is supressed even at relatively low currents. That also means the lights dim quickly if you try to operate them continuously at their nominal power.

Nobody has solved that little issue yet, which is why the updated version of the lamp won’t actually produce nearly as much light as he thinks it does. The extra problem is that the heavily blue tinted light makes you feel like you’re looking at a bright light while your ability to see in color and your ability to focus are actually diminished. The human eye has a shutter that responds to light, so it’s not that readily apparent that you have less than 1/3rd the light.

Reply ↓
Fritoeata on September 24th, 2012 at 4:27 pm said:

Very minor suggestion here…
If you turn your scribe tool on your circle cutter, it won’t make a chamfered angle on the part, instead, the chamfer will be on the scrap.
frito

Reply ↓