Patent ID: 8450942

Claim:
A light emitting diode (LED) driving apparatus, suitable for driving at least an LED string, and the LED driving apparatus comprising: a power switch, having a first terminal coupled to a first node and a second terminal coupled to a second node, wherein the LED sting is coupled between a DC voltage and the first node; a first resistor, coupled between the second node and a ground potential; and a control chip, coupled to a control terminal of the power switch, the first node and the second node, for generating a driving signal in response to a voltage on the second node and a bandgap voltage during an activation phase of the LED driving apparatus, so as to switch the power switch and thus making the LED string to be operated under a constant current for producing light, and further for comparing a detection voltage obtained in response to a voltage on the first node with a predetermined voltage, so as to stop generating the driving signal when the detection voltage is greater than the predetermined voltage.