Abstract: An electronic ballast for controlling the operating behavior and brightness of a gas discharge lamp, includes a full bridge circuit fed with a d.c. voltage (UBUS). The gas discharge lamp is connected as a load of the full bridge circuit, and a control circuit in each case switches on one bridge diagonal and switches off another bridge diagonal of the full bridge circuit, alternatingly. The bridge diagonals each have a regulatable constant current source for regulating a lamp current, and thereby the occurrence of flickering appearances is suppressed. As a result, the lamp can be dimmed over a very wide range of brightnesses.

Abstract: Method and device for controlling the operational performance of at least one gas discharge lamp (10). The control is effected with the aid of a controller (1) the proportional component of which is set in dependence upon an externally applied desired value (SOLL) of an operational parameter of the gas discharge lamp (10), whereby for low brightness desired values the proportional component of the controller (1) is set high, and for great brightness desired values of the gas discharge lamp (10) is set low. In this way it is possible to reliably fire the gas discharge lamp (10) even at low brightness values, without the appearance of a light flash, and at the same time to avoid instabilities in the case of high brightness values of the gas discharge lamp (10).