7 15W Fluorescent Inverter project

This 15W Fluorescent Inverter project is assembled out of defective compact fluorescent tube (CFL).This project will be used to light CFL using a 12V battery. The approximate power output of this project is enough to light 15W CFL tube. The circuit is composed of simple inverter that will generate a high voltage output enough to strike the tube with out heating its filament, thus this simple electronic device is suitable to defective ( burnt out filament ) CFL.
When you connect the circuit to battery, the feedback winding F (8 turns #24 AWG) will assist the primary winding P (16 turns #24 AWG) in turning on the transistor.At the point of operation, voltage is generated to output winding S (270 turns #30 AWG ).this process will continue until the transistor draws the maximum current,and and the current change in the feedback and primary winding is minimal. At this point, the transistor is turned off, and ready for the next cycle.

tested in input side of circuit using 12V battery meter readings are the following
11.023V @ 1.42A, at no load

10.45V @ 0.73A, 15W CFL tube

10.5V @ 1.3A , 2 series 15W CFL



    1. Usted puede usar esa baterĂ­a de 24 voltios.

  2. I see where the + voltage of the battery is connected, but where does the ground(-) voltage connect to? If I can get this to work this would be very helpful. Also, I am using a 6 cell nimh battery (7.2v), and I think this would work with just a little playing around with resistors, right? Thanks.

  3. Kevin good day!
    the negative (-) of battery is connected to the emitter of the transistor and capacitor..I edited the diagram above.
    You are right, you can replace the battery depending of what is available and just replace the value of the resistor. I cant give you the value of the resistors but, as a general info, decreasing the voltage also decreases the value of required resistance. You can tinker the circuit and place any value of your desire but be reminded always that the output of the inverter is high voltage, so avoid touching it.

  4. Hello,

    I have built up the circuit but I am facing an issue with the heat that comes out form the transistor (too much). I am using this circuit to power 8W CCFL tube. Instead of TIP41 I am using BD243C and the power supply is provided by 2 x LiIon batteries in series 7.4V. The 330ohm resistor is replaced with 22ohm/1W since it heats up a lot.
    Please let me know if you have the same issue.
    Open for any advices.


  5. I got the same problem too regarding the excessive heat on both transistor and resistor. What i did is built it with a heatsink and use resistors with higher power rating (5W). This circuit is made simple as possible that we compromise its efficiency. The circuit also is intended for hobby or for emergency use only, so i will not recommend it using for longer period of time. Buts you can modify it and use it as long as you want.

  6. hi.. i am looking some project today for my final year project in electronics..which is a wireless power transfer or wireless electricity for cfl, flourescent bulb rating from 5W to 40W. can you give me some advice how to build it regarding this project or maybe you have some circuit diagram for my project.. pls help me.. tnx a lot .. this site is very wonderful... by the way this is my email add: gta_jag69@yahoo.com