Is it possible to connect in parallel the output channel of different TLE4242G devices?
LITIXTM Linear TLE4242G LED Driver is a high side current source driver.
The LED load is connected between the Q and REF pins. A resistor RREF is connected between REF pin and GND in order to generate a reference voltage VREF.
More specifically, in the device, the voltage VREF is the feedback. This means that the output current is regulated to get a determined voltage across the RREF resistor. Such a voltage can slightly differ from device to device. Due to that it is possible that one device is partially or completely OFF.
For that reason, it is not recommended to connect in parallel 2 or more TLE4242G devices, as shown in the picture below:
The output current, calculated as IQ = VREF/RREF , is regulated through the resistor RREF. Where:
- IQ is the output current,
- VREF is the voltage drop across the resistor RREF and
- RREF is the external resistor, which is placed to regulate the output current.