RDK-268: 1 LED @ 366mA, 85 ~ 265V in, PFC

This document is an engineering report describing a non-isolated LED driver (power supply) utilizing a LNK454DG from the LinkSwitch™-PL family of devices. It contains the power supply specification, schematic, bill of materials, transformer documentation, printed circuit layout, and performance data.

The RD-268 provides a single constant current output of 366 mA with a nominal LED voltage of 3 V.

The board was optimized to operate over a universal AC input voltage range (85 VAC to 265 VAC, 47 Hz to 63 Hz) but suffers no damage over an input range of 0 VAC to 300 VAC. This increases field reliability and lifetime during line sags and swells.

Key benefits of this design are the very high power factor (>0.85), low THD (<25%) and low harmonic content (a significant challenge due to the low output power) and the ability to fit inside the limited space of a candelabra size lamp base.

• Surge protected for high reliability: Meets IEC ringwave and differential mode surge
  

• Meets EN55015 conducted EMI
  

• PF >0.9 at 115 VAC and PF>0.85 at 230 VAC
  

• %ATHD <15% at 115 VAC and <25% at 230 VAC
  

• Meets EN61000-3-2 harmonic current requirements