Patent ID: 8547031
Filing Date: 2013-10-01
Classification: H05B,Y02B

Abstract:
1. A circuit configuration for operating at least one first light emitting diode and one second light emitting diode, the circuit configuration comprising: an operational amplifier having a plus input and a minus input and an output; a device providing a target value and coupled to the plus input of the operational amplifier; at least one first connection and one second connection for the first light emitting diode and one first connection and one second connection for the second light emitting diode, whereby the respective first connection is coupled to a connection for a DC supply voltage, whereby the respective second connections are coupled to each other, forming a connection point; and a current sensing resistor coupled in series between the connection point of the second connections and a reference potential, whereby the voltage drop across the current sensing resistor is coupled to the minus input of the operational amplifier; a first transistor which can be driven in an analog manner, having a control electrode, a reference electrode and a working electrode, the working electrode-reference electrode path of which is coupled in series to the first connection and second connection for the first light emitting diode between a connection for a DC supply voltage and the reference potential; a second transistor which can be driven in an analog manner, having a control electrode, a reference electrode and a working electrode, the working electrode-reference electrode path of which is coupled in series to the first connection and second connection for the second light emitting diode between a connection for a DC supply voltage and the reference potential; a first electronic switch which is coupled in series between the output of the operational amplifier and the control electrode of the first transistor which can be driven in an analog manner; and a second electronic switch which is coupled in series between the output of the operational amplifier and the control electrode of the second transistor which can be driven in an analog manner.