A method for operating an electronic ballast for a luminous means , comprising the steps: detection of an input voltage (Vin) of the electronic ballast by means of an under-voltage monitoring device of a control circuit and detection of the ambient temperature (T) of the electronic ballast by means of a temperature detection device , selection of a dimming characteristic curve in dependence on the detected ambient temperature (T) from several dimming characteristic curves for different ambient temperatures, which are stored in the control circuit , wherein in each case a predetermined under-voltage reference value (V1-V3) is associated with each of the several dimming characteristic curves, which under-voltage reference value in each case represents a minimum tolerable input voltage of the electronic ballast , comparison of the input voltage (Vin) with the under-voltage reference value (V1-V3) associated with the selected dimming characteristic curve and reduction of an electric output power (P) supplied to the luminous means by the electronic ballast according to the selected dimming characteristic curve, if the input voltage (Vin) undershoots the under-voltage reference value (V1-V3) associated with the selected dimming characteristic curve, characterized in that the reduction of the output power (P) of the electronic ballast takes place by an appropriate activation of an inverter of the electronic ballast according to the selected dimming characteristic curve, and that a minimum dimming level (DL) which is the same for all dimming characteristic curves, is predetermined, so that the luminous means is not dimmed more than with the minimum dimming level (DL) at low input voltages. detection of an input voltage (Vin) of the electronic ballast by means of an under-voltage monitoring device of a control circuit and detection of the ambient temperature (T) of the electronic ballast by means of a temperature detection device , selection of a dimming characteristic curve in dependence on the detected ambient temperature (T) from several dimming characteristic curves for different ambient temperatures, which are stored in the control circuit , wherein in each case a predetermined under-voltage reference value (V1-V3) is associated with each of the several dimming characteristic curves, which under-voltage reference value in each case represents a minimum tolerable input voltage of the electronic ballast , comparison of the input voltage (Vin) with the under-voltage reference value (V1-V3) associated with the selected dimming characteristic curve and reduction of an electric output power (P) supplied to the luminous means by the electronic ballast according to the selected dimming characteristic curve, if the input voltage (Vin) undershoots the under-voltage reference value (V1-V3) associated with the selected dimming characteristic curve, characterized in that the reduction of the output power (P) of the electronic ballast takes place by an appropriate activation of an inverter of the electronic ballast according to the selected dimming characteristic curve, and that a minimum dimming level (DL) which is the same for all dimming characteristic curves, is predetermined, so that the luminous means is not dimmed more than with the minimum dimming level (DL) at low input voltages. <EOS>