System comprising, - an LED series circuit (LED1... LEDn) having a first (k) and a second (n-k) number of LEDs connected in series, and - a switching converter for powering the LED series circuit (LED1...LEDn), the switching converter comprising o a first and a second pole for applying an input voltage, o a longitudinal inductance, o a current sensor formed as an ohmic resistor, o a PWM drive circuit, ∘ a switching transistor, wherein a first terminal of the longitudinal inductance is connected to the first pole and a further terminal of the longitudinal inductance can be connected to a first terminal of the LED series circuit (LED1... LEDn), wherein a second terminal of the LED series circuit (LED1... LEDn) is connected to the second terminal via the current sensor, which is in the form of an ohmic resistor, the switching transistor being driven by the PWM drive circuit, the PWM drive circuit being supplied with a signal from the current sensor, which is in the form of an ohmic resistor, the current sensor, which is in the form of an ohmic resistor, being used to detect a total current through the LED series circuit (LED1... LEDn) and the switching transistor. LEDn) and the switching transistor, and the PWM drive circuit switching the switching transistor as a function of the signal supplied, characterized in that the further terminal of the longitudinal inductance is directly connected to the first terminal of the LED series circuit (LED1...LEDn), and the switching converter is designed in such a way that the first number (k) of LEDs (LED1, LED2) cannot be bridged by a switching path of the switching transistor, the second number (n-k) of LEDs (LED3... LEDn) can be bridged by means of the switching path of the switching transistor, the switching transistor, in accordance with the signal of the PWM drive circuit, periodically connecting the further terminal of the series inductance via the first number (k) of LEDs (LED1, LED2) and the current sensor formed as an ohmic resistor to the second pole, wherein a forward voltage of the first number (k) of LEDs (LED1, LED2) is lower than the minimum possible operating voltage of the switching converter. - an LED series circuit (LED1... LEDn) having a first (k) and a second (n-k) number of LEDs connected in series, and - a switching converter for powering the LED series circuit (LED1...LEDn), the switching converter comprising o a first and a second pole for applying an input voltage, o a longitudinal inductance, o a current sensor formed as an ohmic resistor, o a PWM drive circuit, ∘ a switching transistor, o a first and a second pole for applying an input voltage, o a longitudinal inductance, o a current sensor formed as an ohmic resistor, o a PWM drive circuit, ∘ a switching transistor, wherein a first terminal of the longitudinal inductance is connected to the first pole and a further terminal of the longitudinal inductance can be connected to a first terminal of the LED series circuit (LED1... LEDn), wherein a second terminal of the LED series circuit (LED1... LEDn) is connected to the second terminal via the current sensor, which is in the form of an ohmic resistor, the switching transistor being driven by the PWM drive circuit, the PWM drive circuit being supplied with a signal from the current sensor, which is in the form of an ohmic resistor, the current sensor, which is in the form of an ohmic resistor, being used to detect a total current through the LED series circuit (LED1... LEDn) and the switching transistor. LEDn) and the switching transistor, and the PWM drive circuit switching the switching transistor as a function of the signal supplied, characterized in that the further terminal of the longitudinal inductance is directly connected to the first terminal of the LED series circuit (LED1...LEDn), and the switching converter is designed in such a way that the first number (k) of LEDs (LED1, LED2) cannot be bridged by a switching path of the switching transistor, the second number (n-k) of LEDs (LED3... LEDn) can be bridged by means of the switching path of the switching transistor, the switching transistor, in accordance with the signal of the PWM drive circuit, periodically connecting the further terminal of the series inductance via the first number (k) of LEDs (LED1, LED2) and the current sensor formed as an ohmic resistor to the second pole, wherein a forward voltage of the first number (k) of LEDs (LED1, LED2) is lower than the minimum possible operating voltage of the switching converter.