A very simple led driver electronic project can be designed using LNK404EG driver , manufactured by Power Integrations.
The LNK404EG led driver electronic project is designed to drive 26.5 V LED at 260 mA from an input voltage range of 185 VAC to 264 VAC.
LinkSwitch-PH ICs allow the implementation of cost effective and low component count LED drivers which both meet power factor and harmonics limits but also offer enhanced end user experience.
The LNK404EG also provides a sophisticated range of protection features including autorestart for open control loop and output short-circuit conditions.
Inductor L1-L4, R2, R3, R8, R9, and C10, provide EMI filtering together with C17 Y capacitor. Small bulk capacitor C10 is required for a low impedance path for the primary switching current.
Diode D6 and C8 detect the peak AC line voltage. This voltage is converted to a current into the V pin via R4, R7 and R13. Diode D7 and R13 provide additional V pin current during deep dimming to inhibit the undervoltage threshold of the IC. The presence of D7 disables the undervoltage feature of the IC without affecting the overvoltage protection.
Diode D1, R26, R28, R25 and C16 clamp the drain voltage to a safe level from the leakage inductance voltage spike. Diode D5 is necessary to prevent reverse current from flowing through the LinkSwitch-PH device.
Diode D3, C6, R5, and R18 create the primary bias supply.
Capacitor C12 is the main supply for the LinkSwitch-PH, which is charged to ~6 V at start-up from an internal high-voltage current source tied to the device DRAIN pin .
Diode D2 rectifies the secondary winding while capacitor C4 filters the output. VR3, C15, R23, and Q2 provide an open load overvoltage protection function.
Resistors R16 act as a damping network preventing the input current from ringing negative when the TRIAC dimmer turns on and thereby creating flicker. SCR Q3, R11, R12 and C13 shorts R16 after the transient has subsided and thus saves unnecessary power loss on R16. Capacitors C9, C11 and R10 and R17 provides the latching current for the TRIAC once conducting and also helps further dampen ringing.
Transformer used for this project has the following specifications :