No Electrolytic Capacitor, High Efficiency High Power Factor 15 W LED Driver Using LinkSwitch PH LNK417EG
This LED lighting design example report describes an isolated, power factor corrected, very high efficiency LED driver designed to drive a 30 V LED string at a current of 500 mA (nominal). The input voltage range is 90 VAC to 265 VAC. The LED driver uses a LNK417EG device from the LinkSwitch-PH family of ICs. This integrated controller and 725 V MOSFET dramatically reduces the complexity and component count of the solution. The key design goals were to achieve the highest possible efficiency and eliminate electrolytic capacitors. Both are key factors for increasing the lifetime and reliability of LED drivers making this solution ideal for industrial and commercial applications. This document contains the LED driver specification, schematic, bill of material, transformer documentation and typical performance characteristics.
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No Electrolytic Capacitor, High Efficiency High Power Factor TRIAC Dimmable 7 WTYP LED Driver Using LinkSwitch PH LNK403EG
This design example report describes a power-factor corrected dimmable LED driver designed to drive an LED string of 18 V at a current of 0.38 A (both nominal) from an input voltage range of
90 VAC to 265 VAC. The LED driver utilizes the LNK403EG from Power Integrations. The design specifically eliminates electrolytic capacitors which limit operating life, especially when operated at high temperature. 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. This includes ultra-wide dimming range, flicker-free operation (even with low cost with AC line TRIAC dimmers) and fast, clean turn on. The topology used is an isolated flyback operating in continuous conduction mode. Output current regulation is sensed entirely from the primary side eliminating the need for secondary side feedback components. No external current sensing is required on the primary side either as this is performed inside the IC further reducing components and losses. The internal controller adjusts the MOSFET duty cycle to maintain a sinusoidal input current and therefore high power factor and low harmonic currents. The LNK403EG provides a sophisticated range of protection features including auto-restart for open control loop and output short-circuit conditions. Line overvoltage provides extended line fault and surge withstand, output overvoltage protects the supply should the load be disconnect and accurate hysteretic thermal shutdown ensures safe average PCB temperatures under all conditions. For this design a focus was given to compatibility with as wider range of dimmers and as large of a dimming range as possible, at both 115 VAC and 230 VAC. However simplification of the design is possible for single input voltage operations, non-dimming or operation with a limited range of (higher quality) dimmers. This document contains the LED driver specification, schema
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1.1 W Power Factor Corrected LED Driver (Non-Isolated) Using LinkSwitch?-PL LNK454DG
This LED lighting reference design report describes an isolated, power factor corrected, very high efficiency LED driver designed to drive an LED string of 30 V at a current of 500 mA (both nominal) from an input voltage range of 90 to 265 VAC. The LED driver uses a LNK407EG device from the LinkSwitch-PH family of ICs. This integrated controller and 725 V MOSFET dramatically reduces the complexity and component count of the solution. The key design goals were to achieve the highest possible efficiency and eliminate electrolytic capacitors. Both are key factors for increasing the lifetime and reliability of LED drivers making this solution ideal for industrial and commercial applications. This document contains the LED driver specification, schematic, bill of material, transformer documentation and typical performance characteristics. The design was based on the reference design board RD-194 with simple component changes to meet the new specification.
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1.1 W Power Factor Corrected LED Driver (Non-Isolated) Using LinkSwitch-PL LNK454DG
This engineering report describes a non-isolated LED driver (power supply) utilizing a LNK454DG from the LinkSwitch(TM)-PL family of devices. The RD-268 provides a single constant current output of 366 mA with a nominal LED voltage of 3 V. Key benefits of this design are the very high power factor (>0.85), low THD (200) are connected in parallel, however, by using individual lamps that have PFC allows the overall fixture to meet PFC and THD requirements with the large energy savings that come from using LEDs vs. incandescent lamps. The form factor of the board was chosen to meet the requirements for standard candelabra shaped LED replacement lamps. The output is non-isolated and requires the mechanical design of the enclosure to isolate the output of the supply and the LED load from the user. The document contains the power supply specification, schematic, bill of materials, transformer documentation, printed circuit layout, and performance data.
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5 W Dimmable Power Factor Corrected LED Driver (Non-Isolated) Using LinkSwitch(TM)-PL LNK457DG
This engineering report describes a non-isolated LED driver (power supply) utilizing a LNK457DG from the LinkSwitch-PL family of devices. The RD-251 provides a single constant current output of 350 mA over an LED string voltage of 12 V and 18 V. The output current can be reduced using a standard AC mains TRIAC dimmer down to 1% (3 mA) without instability and flickering of the LED load. The board is compatible with both low cost leading edge and more sophisticated trailing edge dimmers. The form factor of the board was chosen to meet the requirements for standard pear shaped (A19) LED replacement lamps. The output is non-isolated and requires the mechanical design of the enclosure to isolate the output of the supply and the LED load from the user. The document contains the power supply specification, schematic, bill of materials, transformer documentation, printed circuit layout, and performance data.
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