A very simple high efficiency led driver circuit can be designed using LNK454DG controller designed by Power Integrations . This LNK454DG led driver is configured as non-isolated discontinuous flyback converter designed to drive LED strings at voltages of 2.5 V to 3.5 V with an output current of 366 mA The circuit meets both line surge and EMI requirements and the low component count allows board dimensions required for LED candelabra bulb replacement applications. LNK454DG led driver is very easy to be configured and require few external electronic parts. LED Driver Schematic Two differential pi (Ï€) filter EMI stages are used with C1, R1, L1 and C2 forming one stage and C2, L2, R2 and C3 the second.The incoming AC is rectified by BR1 and filtered by C1, C2 and C3. The total effective input capacitance, the sum of C1, C2 and C3, was selected to assure correct zero crossing detection of the AC input by the Switch-PL device and to meet high power factor and low THD. Due to the limited in...