Light emitting diode driving circuit and system

摘要

A light emitting diode (LED) driving circuit is provided. The LED driving circuit includes: at least one LED driving module, coupled to the at least one LED series, for driving the corresponding LED series; and a voltage regulating module, coupled to the at least one LED driving module, for providing a regulation signal according to an output signal from the at least one LED driving module, wherein an input voltage of the at least one LED series is regulated according to the regulation signal.

主权项

1. A light emitting diode (LED) driving circuit, comprising:
at least two LED driving modules, each of the at least two LED driving modules is arranged to drive a corresponding LED series of at least two LED series, wherein the each of the at least two LED driving modules comprises:
a driving transistor having a drain connected to a first end of the corresponding LED series; andan operational amplifier comprising a negative input end connected to a source of the driving transistor and a positive input end coupled to a driving voltage, wherein a second end of the corresponding LED series is provided with a first voltage from a voltage source, and the positive input ends of the operational amplifiers of the at least two LED driving modules are connected to the driving voltage together; and a voltage regulating module, coupled to the at least two LED driving modules, for providing a regulation signal to a controller according to drain voltages at the drains of the driving transistors in the at least two LED driving modules.