The invention relates to an operating device (BG) for lamps (LM), comprising an interface (IFi), by means of which the device (BG) may be provided with external dimming values. The device (BG) converts said provided external dimming values into internal dimming values on the basis of which the control of the connected lamps (LM) is achieved, the internal dimming values being of higher resolution than the external dimming values. According to the invention, the operating device (BG) is designed such that the conversion of the external dimming values into internal dimming values may be programmed. The operating device (BG) can particularly also be designed such that said conversion can be programmed with regard to the dynamics thereof. A programming can be provided by a time conversion relationship (linear, logarithmic or exponential time curve etc.) by means of which an internal dimming value corresponding to an external dimming value is reached.