a dc / ac cold cathode fluorescent lamp inverter circuit includes a transformer with a primary winding and a secondary winding for providing increased voltage to a ccfl , a first and second mosfet switches for selectively allowing direct current of a first polarity and a second polarity to flow through the transformer respectively . the primary and secondary windings of the transformer are electrically coupled to ground . a capacitor divider is electrically coupled to the ccfl for providing a first voltage signal representing a voltage across the ccfl . a first feedback signal line receives the first voltage signal . a timer circuit is coupled to the first feedback signal line for providing a time - out sequence of a predetermined duration when the first voltage signal exceeds a predetermined threshold . a protection circuit shuts down the first switch and the second switch when the first voltage signal exceeds the predetermined threshold after the predetermined duration .