This 40W fluorescent inverter project is powered by 555 timer IC and use to drive fluorescent tubes, compact fluorescent lamp (CFL) and even defective fluorescent tube.

From a 12V supply voltage, timer IC generates square wave voltage of about 4.8 kHz. The primary winding (16 turns of #22 AWG) will generate current pulses of about 4A, and in return will induce a high voltage at the secondary winding (450 turns of #30 AWG) of the inverter. This voltage is enough to strike the fluorescent tube even if the filament is not heated thus very suitable to tubes with broken filaments (burnt out filaments).

This inverter project is very suitable in lighting defective fluorescent tubes, thus helps in minimizing tubes disposal problems. The inverter also can light two 40W tubes in series.

Transformer Construction:
The core used is a antenna bar or the ferrite rod. First wind 16 turns of #22 AWG magnetic wire, the above its winding, wind the secondary or the high voltage winding using #30AWG magnetic wire.
windings using ferrite rod
Note: The output of the inverter produces very high voltage and can cause electrocution. Avoid touching it.


  1. mi pregunta puede funcionar con dos tubos de 40 watts en serie o 2 tubos de 20 watts como es la cosa 40 o 20

  2. Good day!
    As what i understand about your comment in Spanish(I cant understand Spanish actually)..
    We can use two 40W tube in series even-though our project is rated only 40W, but the emitted light is not as bright as using only one 40W tube.
    Or you can use two 20W tube in series.
    Just feel free to experiment..

  3. HI,
    What i understand is even upto 40W CFL can be powered from this circuit. Can you also provide the iron core details for the transformer, thanks for the effort.

  4. Thanks for asking. I add the details above.

  5. Hi,
    This is Mohan.
    Can I use Ordinary Transformer instead of winding in ferrite rod.
    And one more thing can I use 2 or 3 15W CFL in parallel.