Electronic ballast for fluorescent lamp

Electronic ballast for at least one gas discharge lamp (LA), having a to an alternating voltage source (U0) That can be connected rectifier circuit (2), one to the output of the rectifier circuit (2) connected smoothing circuit (3) for generating an intermediate circuit voltage (UZ) And with the intermediate circuit voltage (UZ)-Fed inverter (4), at whose output a connection for the lamp (LA) containing the load circuit (5) is connected, wherein said smoothing circuit (3) is formed by a switching regulator having an inductance (L1) and the ballast further comprises a control circuit (6), which at least one operating parameter (Ui, IL, UZ) Of the smoothing circuit (3) is detected and a controllable switch (S1) of the switching regulator in dependence on the value of the detected operating parameter (Ui, IL, UZ) Drives, characterized, that the control circuit (6) includes an analog / digital converter (ADC1) For converting the detected operating parameter (Ui, IL, UZ) Of the smoothing circuit (3) has in one of at least two bit digital value consisting, wherein the control circuit (6) based on this digital value in a digital control loop ...