Patent ID: 9001482
Filing Date: 2015-04-07
Classification: H02H,H05B,Y02B

Abstract:
1. A short-circuit protection circuit of a light emitting diode (LED), for protecting a plurality of LED strings from a short-circuit condition, the short-circuit protection circuit comprises: a short-circuit protection unit, coupled to the plurality of LED strings and configured to execute a short-circuit protection; a control unit, coupled to the short-circuit protection unit and the LED strings and configured to control the short-circuit protection unit according to at least one of a feedback voltage and a compensation voltage, so as to determine whether to trigger the short-circuit protection; and a plurality of detection units, respectively coupled to the LED strings and respectively detecting a cathode terminal voltage of each of the LED strings when the short-circuit protection is triggered to respectively determine whether the cathode terminal voltage of each of the LED strings is larger than a protection voltage, wherein when the detection unit corresponding to at least one LED string of the LED strings detects that the cathode terminal voltage of at least one of the LED string is larger than the protection voltage, a current is prohibited from flowing through the at least one LED string by the detection unit, wherein the feedback voltage is generated according to a cross voltage of one of the LED strings, the compensation voltage is generated according to a comparison result between the feedback voltage and a reference voltage, and the compensation voltage is employed to control a power supply of the LED strings.