Fairchild – FL7733A: Primary Side Regulated LED Driver with PFC


The FL7733A is a highly-integrated PWM controller with advanced Primary Side Regulation (PSR) technique to minimize components in low to mid-power LED lighting converters. Using an innovative TRUECURRENT® technology to provide tight tolerance constant current (CC) output, this LED driver enables designs with CC tolerance of <±1% over the universal line voltage range to meet stringent LED brightness requirements.


  • <±3% total CC tolerance over all conditions
  • <±1% from 50% to 100% load voltage variation
  • PSR control
  • >0.9 power factor
  • <200ms start-up (at 85VAC)
  • Adaptive feedback loop control
  • <±1% over universal line voltage variation
  • <±1% with ±20% magnetizing inductance variation
  • 80VAC to 308VAC application input voltage range
  • <10% THD over universal line input range
  • Internal high voltage start-up with VDD regulation