Multi-segment LED driving circuit

摘要

Disclosed is a multi-segment LED driving circuit used in an AC operating mode for outputting a drive current to drive a plurality of serially connected LED strings. The LED driving circuit includes at least one detection part, at least one comparison part and at least one adjusting part. The detection part detects an input voltage and an output voltage at both ends of each string and its next string to form a detected value provided for the comparison part to compare the detected value with a reference value to turn on or off the adjusting part so as to control the strings through which the drive current passes and then sequentially drives the strings to emit light. The LED driving circuit can adjust the load of the circuit immediately based on the change of voltage value of the AC power to ensure the stability of the drive current.

主权项

1. A multi-segment LED driving circuit, used in an AC operating mode for driving a plurality of LEDs to ensure a constant current value of a drive current passing through the LEDs, and the LEDs being divided into a plurality of strings, and having a node between every two adjacent strings, characterized in that:
the multi-segment LED driving circuit comprises at least one detection part, at least one comparison part and at least one adjusting part, and the detection part is electrically coupled to the strings, the comparison part is electrically coupled to the detection part and the adjusting part, and the adjusting part is electrically coupled to each string; the detection part detects an input voltage and an output voltage at both ends of each and the next string thereof to form a detected value, and the comparison part is enabled to compare an operating voltage value fed back by the adjusting part with a reference value to output a driving signal and adjust the adjusting part, so as to control the strings that the drive current passes, and then sequentially drive the LEDs to emit light.