Supply voltage management

The present document relates to a driver circuit for a solid state light source. In particular, the present document relates to the start-up and/or the maintenance of a supply voltage for the integrated circuit of a driver circuit. A driver circuit (300) for a solid state light source (309) is described. The driver circuit (300) comprises a switched-mode power converter comprising a power converter switch (202) and a transformer (307). The switched-mode power converter is configured to convert an input voltage (230) at an input of the switched-mode power converter into an output voltage (231) at an output of the switched-mode power converter (200). Furthermore, the driver circuit (300) comprises a controller (306) configured to generate a gate control signal (232) for putting the power converter switch (202) into an on-state and/or an off-state. In addition, the driver circuit (300) comprises a supply voltage capacitor (310) coupled to the controller (306) and configured to provide a supply voltage to the controller (306). A primary coil (314) of the transformer (307) is arranged in series with the power converter switch (202), a secondary coil arrangement (313, 315) of the transformer (307) is configured to provide the output voltage (231), the secondary coil arrangement (313, 315) is coupled to the supply voltage capacitor (310) via a supply voltage transistor (350), and the supply voltage transistor (350) is controlled such that the supply voltage provided by the supply voltage capacitor (310) lies within a pre-determined voltage interval.