Afraid of the dark? Built a simple Joule Thief circuit and would like to go further? Just want to have a cool blue light to show off to friends? Let me present..... The Joule Thief 10x10 LED Lamp!
The Joule Thief 10x10 LED Lamp! Runs on one to four AA batteries. Lights up 100 LED's, illuminates your night!
This is a simple LED project build with parts I have on hand,
100 3mm LED's (Bought from ebay)
Toroidal core (Salvaged from CFL lamps)
Enameled wire/Magnet Wire (salvaged)
100 ohm resistor (values up to 1k should work)
2N2222A transistor (The TO-92 version of it)
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Step 1: Building the Joule Thief Circuit + Testing
Sorry for the lack of pictures..... I got too excited when building it and forgot to take pictures.....
The Joule Thief is a minimalist self-oscillating voltage booster that is small, low-cost, and easy to build; typically used for driving light loads. It can use nearly all of the energy in a single-cell electric battery, even far below the voltage where other circuits consider the battery fully discharged (or "dead"). Hence the name, which suggests the notion that the circuit is stealing energy or "joules" from the source. The term is a pun on the expression "jewel thief": one who steals jewelry or gemstones.
The circuit uses the self-oscillating properties of the blocking oscillator, to form an unregulated voltage boost converter. The output voltage is increased at the expense of higher current draw on the input.
Anyways, I searched for Joule Thief and got a schematic for it. I built the circuit exactly the same as the schematic but changed the transistor and the resistor value. After its completed I tested it by connecting it to a LED.
Step 2: Build LED Board.
100 blue 3mm LED's are wired in parallel and is connected to the output of the Joule Thief. Some solid core copper wires are use to connect the LED's together.......
Step 3: Test All Connections for Errors.
All connections are tested for shorts and errors. After testing, I put a AA battery in and IT COMES ALIVE!!!!!!
Step 4: Completed.....
The project is completed and it sure is bright! This project is a simple project and it took me about 2 hours to build it. Try making one and just look at it's awesomeness......
I've tested the circuit and it seems to run for about 40 hours before dimming and switching off. That's with one fresh battery connected. (Voltage: 1.5v+/- = start ------ 0.65v end)
Thank you for reading and I hope you have enjoyed reading this instructable!