2 20W 12-120V simple inverter project

The output of this inverter project is square wave 160ma max at 720 ohm. Load must not include equipment with motor that operates in purely sinewave source of 50 or 60 Hz frequency .The circuit is good in lighting like cfls and incandescent lamps. But ensure first that the load must not exceed the 30W for proper operation.

Resistor is 10W 39 ohms and transformer is rated 5A of 120 to 12-0-12. For more protection, provide 3A fuse and a switch in series to the battery

Other useful inverter:
15W fluorescent inverter - Use only 1 transistor, very cheap
Modified sinewave inverter - cheap modified sinewave
simple fluorescent inverter - uses 555IC as the driver


  1. Hello,Thank you for putting up this simple inverter.
    Will this one work for 24 VDC Battery - 220V CFLS - 20W?
    Thank you for your help.

  2. You can, just double the resistance to 78 ohms. Two 39 ohms in series.
    Be careful with the output. Don't forget to add heatsink on the transistor or even on the resistor.