A driver circuit for coupling an electromagnetic ballast to a light circuit comprising one or more light emitting diodes, the driver circuit comprising - a rectifier bridge with an input for exchanging a first current signal with the electromagnetic ballast and with an output for providing a second current signal to the light circuit, and - a protection circuit (21-24, 25-27) for protecting the electromagnetic ballast against one or more parameters of the first current signal obtaining a value larger than a threshold value, characterized in that the driver circuit further comprises a further switch arranged to control an amount of power supplied to the light circuit, wherein in a non-conducting mode of the further switch, the second current signal flows via a diode to the light circuit and is further used for charging a capacitor and wherein in a conducting mode of the further switch, the second current signal flows through this further switch to ground, and the light circuit gets its power only from the charged capacitor, wherein the parameter is an average value of a rectified version of the first current signal, and the protection circuit (25, 27) comprising a detector for detecting the average value of the rectified version of the first current signal and for providing a detection result if the average value exceeds the threshold value, and comprising a switch for, in response to the detection result, interrupting the second current signal; or wherein the parameter is a peak value of the first current signal, and the protection circuit (26, 27) comprising a detector for detecting the peak value of the first current signal and for providing a detection result if the average value exceeds the threshold value, and comprising a switch for, in response to the detection result, interrupting the second current signal. - a rectifier bridge with an input for exchanging a first current signal with the electromagnetic ballast and with an output for providing a second current signal to the light circuit, and - a protection circuit (21-24, 25-27) for protecting the electromagnetic ballast against one or more parameters of the first current signal obtaining a value larger than a threshold value, characterized in that the driver circuit further comprises a further switch arranged to control an amount of power supplied to the light circuit, wherein in a non-conducting mode of the further switch, the second current signal flows via a diode to the light circuit and is further used for charging a capacitor and wherein in a conducting mode of the further switch, the second current signal flows through this further switch to ground, and the light circuit gets its power only from the charged capacitor, wherein the parameter is an average value of a rectified version of the first current signal, and the protection circuit (25, 27) comprising a detector for detecting the average value of the rectified version of the first current signal and for providing a detection result if the average value exceeds the threshold value, and comprising a switch for, in response to the detection result, interrupting the second current signal; or wherein the parameter is a peak value of the first current signal, and the protection circuit (26, 27) comprising a detector for detecting the peak value of the first current signal and for providing a detection result if the average value exceeds the threshold value, and comprising a switch for, in response to the detection result, interrupting the second current signal.