The invention relates to an electronic ballast with pre-heating function for operating low pressure discharge lamps. Known electronic ballasts have a current inverter that provides at least one load circuit. Said load circuit comprises a discharge lamp and serial resonant circuit whose capacitor is connected parallel to the discharge lamp. The discharge lamp has heatable electrodes and a transformer whose primary winding is connected in series to the capacitor and whose two secondary windings are both connected in parallel to the electrodes. Said transformer is designed in such a manner that it quickly reaches the state of saturation once it is switched on.
