Constant current LED driver based on flyback structure with primary side control

The design of a 3W constant current LED driver based on flyback structure with primary side control technology is proposed, which eliminates the opto-isolated feedback and secondary regulation circuits which are required in conventional designs. The principle of constant current and constant voltage of the circuit is analyzed, and parameters of the circuit are introduced. The constant current accuracy of the circuit under 60V–260V AC input voltage is 6.4%. The experimental results show that the circuit has the advantages of simple structure, high constant current precision and high stability.

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