沈霞,李红伟,许瑾.基于无光耦反激变换器的LED驱动电源设计[J].电测与仪表,2012,49(7):97-100. SHEN Xia , LI Hong-wei , XU Jin.Design of LED Driver Power Supply Based on Flyback Converter without Photocoupler[J].Electrical Measurement & Instrumentation,2012,49(7):97-100.
基于无光耦反激变换器的LED驱动电源设计
Design of LED Driver Power Supply Based on Flyback Converter without Photocoupler
In order to realize constant current control and isolation between input and output,in traditional LED power supply using Flyback converter as main circuit,photocoupler is needed to transfer the feedback signal from primary side to secondary side.Consider of the large size of photocoupler and the influence of current transfer ratio due to temperature variation,the Flyback converter with primary side control is used as main circuit to decrease the number of components and the influence of the temperature.Without photocoupler the main circuit has less cost,smaller size,higher power density and less influence of temperature.With this power supply,the LED current can be regulated to realize the control of the lightness and the voltage of the LED can also be controlled to realize the open protection of LED.
