Introduction: How to Make a Joule Thief - Boost Converter

About: Rudy Explor: Hack, Test, project and experiment is: Simply a quest for discovery. Here are some of my experiences, life hacks, product testing and random weekend

Joule Thief allows to use almost all of the energy of a single cell or a single cell battery.

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Thus, the circuit Joule Thief permits to increase the voltage of the source (battery, battery) above the minimum voltage required to operate the device connected to it. We can use the batteries and rechargeable batteries for longer, even when the voltage of the latter drops below their voltage, the joule thief standpipe. Joule Thief will extract the last available battery joules or acbcumulateur, hence its name!

The joule (symbol: J) is a unit derived from the international system for quantifying energy, 1 joule is the energy required to raise one apple (100 grams) of a meter in the Earth's gravity field.

How Joule Thief for example: at the entrance, it was 1.5 Volts * 1.0 Ampere = 1.5 W, the output was 3.0 Volts 0.4 Amps * = 1.2 W 0.3 W (losses)

To make a Joule Thief you will need the following equipment :

  • An LED 3v
  • AA 1.5V battery
  • Resistance of 500 Ohms 2 Ohms
  • An NPN transistor
  • A ferrite core
  • 60 cm double wire


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Step 1: Ferrite Cores

We will therefore surrounded with a minimum of 15 rounds Around of the Ferrite Core.

Then we will connect two different wire : a blue and red that will be connected together.

Step 2: Resistor

We will connected : one of the two wire remaining to resistor.

And of the resistor at the "Base" of transistor.

Step 3: Transistor

Then, connect the "Collector" to the remaining wire of the Ferrite Core.

And the remaining wire of the Ferrite Core at the positive (+) of the LED.

Then connected the negative (-) the battery on "Emitter" of transistor.

And "Emitter" at (-) negative of the LED.

Step 4: Battery

And finally we will connect to positive (+) of the battery with the two wires that we have grouped first.

So you know now how to increase a Direct Current.

Pretty cool ! Is not it?
I hope you enjoyed this instructable.

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