CONTROL CIRCUIT FOR LED AND CORRESPONDING OPERATING METHOD

摘要

The drive circuit is suitable for an LED array, comprising a number of clusters of LEDs, with one cluster comprising a number of LEDs which are arranged in series and are connected to a supply voltage (UBatt). A semiconductor switch (transistor T) is arranged in series between the LED and the supply voltage and allows the LED current to be supplied in a pulsed manner. A measurement resistor (Rshunt) for measuring the LED current is arranged in series between the LED and ground, with a control loop controlling the semiconductor switch such that a constant mean value of the LED current is achieved.