| 摘要 |
The invention relates to a control circuit for a LED array. The inventive circuit consists of at least two lines of LEDs, whereby a line consists of several LEDs mounted in series and connected to a distribution voltage (UBatt). A semiconductor switch (T) is connected in series between each LED line and the corresponding distribution voltage and enables to supply the LE D current in a clocked manner. A measuring shunt (RShunt) is connected in seri es in relation to the LEDs and in the branch for the conducting-state current (IF) and between the LEDs and the ground. A control circuit controls the semiconductor switch (T) of a first LED line, hereafter referred to as maste r line, in such a way that a constant mean value of the LED current is obtaine d, whereby the master line is provided with a given number X of LEDs in the lin e thereof. Said control circuit also controls at least the semiconductor switc h (T2) of an additional LED line (slave line).
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