Patent ID: 8143799
Filing Date: 2012-03-27
Classification: H05B,Y02B

Abstract:
1. A light emitting diode driving circuit configured to drive a light emitting diode load, comprising: a transformer having a primary side and a secondary side; a rectifying filtering circuit electrically coupled to the secondary side and having a first output terminal; a pulse width modulation integrated circuit electrically coupled to the primary side; a constant current circuit having a second output terminal, wherein the light emitting diode load is electrically coupled between the first output terminal and the second output terminal; and a feedback circuit having a first input terminal and a second input terminal, wherein the first input terminal is electrically coupled to the first output terminal to receive a first voltage, the second input terminal is electrically coupled to the constant current circuit to receive a second voltage, the second voltage varies a conduction status of the light emitting diode load, and the feedback circuit is configured to control the pulse width modulation integrated circuit according to the first voltage and the second voltage.