Device (V) for controlling at least one
light source (LED), comprehensive - a lamp driver (T) with at least two channels (ch), - a measuring device (M) and - a
control unit (CU), wherein each channel (ch) is assigned a PWM modulation unit (PWM), and wherein each of the PWM modulation units (PWM) can be controlled separately and individually by the
control unit (CU), and wherein each of the PWM modulation units (PWM) is configured to switch exactly one
current source (IQ), and wherein each of the current sources (IQ) is designed to be dependent on a PWM period (t PWM ) periodic PWM output
signal of its associated PWM modulation unit (PWM) to supply a
light source (LED) with electrical energy, whereby an electrical
lamp current generated by the associated
current source (IQ) flows through the lamp (LED), and / or wherein an electrical lamp
voltage applied by the associated
current source (IQ) is applied to the lamp (LED) relative to a supply line (VL) of the current sources (IQ), and wherein the respective PWM output
signal of each PWM modulation unit (PWM) comprises a PWM pulse with a rising edge and a falling edge, and wherein a switch-on time (t E ) correlates with the rising edge or the falling edge of the PWM pulse, and where the PWM period (t PWM ) corresponds to a time period from the rising edge of the PWM pulse to the rising edge of the immediately following PWM pulse, and where the
control unit (CU) is configured to send a
control signal (CS) to the PWM modulation units (PWM) in order to determine the respective switch-on time (t E ) of the PWM pulses output by the control unit (CU) addressed PWM modulation units (PWM) per PWM modulation unit (PWM) separately and individually to each other within the PWM period (t PWM ) in such a way that - a resulting
total current (i(t)) of the lamp currents and / or a total
voltage (V Ges ) of the lamp voltages in the supply line (VL) compared to a reference potential (GND) over the PWM period (t PWM ) corresponds to a nearly constant value and / or - an effective value of an alternating
signal component of the resulting
total current (i(t)) of the lamp currents and / or the total
voltage of the lamp voltages in the supply line (VL) of the current sources (IQ) relative to the reference potential (GND) over the PWM period (t PWM ), wherein the measuring device (M) is designed to
record a measured value (MW), wherein the measured value (MW) is a measured value for the resulting
total current (i(t)), and / or the measured value (MW) is a measured value for the total voltage (V Ges ) in the supply line (VL) of the current sources (IQ) compared to the reference potential (GND), wherein the control unit (CU) is arranged to send the
control signal (CS) depending on the measured value (MW), wherein the control unit (CU) is arranged to send the
control signal (CS) when - a deviation of the measured value (MW) from a predetermined and / or calculated mean value (MMW) exceeds a predetermined first threshold value, or - a deviation of a direct signal component (GSA) of the measured value (MW) from a predetermined comparison value is greater than a predetermined second threshold value, and wherein the control unit (CU) is configured to carry out this method until the deviation of the measured value (MW) from the mean value (MMW) is less than or equal to the first threshold value or until the deviation between the direct signal component (GSA) and the comparison value is less than or equal to the second threshold value.