Various embodiments provide an electronic ballast for operation of at least one discharge lamp, with the electronic ballast having an apparatus for power factor correction with a voltage converter. The voltage converter itself includes an inductance, a diode and a switch. A control apparatus, which produces a square-wave signal as a control signal to the switch of the apparatus for power factor correction, includes an I regulator. This produces a first component of the on time of the control signal. In order to react to short-term power demands in the load circuit for example on ignition of the discharge lamp, an electronic ballast furthermore may include a power determining apparatus, which is coupled to the control apparatus, with the control apparatus being designed to vary the control signal as a function of the power consumed in the discharge lamp.