Datasheet Summary
Integrated Critical-Mode PFC and Quasi-Resonant Current-Mode PWM Lightning Controller
Description The highly integrated FL7921R bines a Power Factor
Correction (PFC) controller and a Quasi- Resonant PWM controller. Integration provides cost effect design and allows for fewer external ponents.
For PFC, FL7921R uses a controlled on- time technique to provide a regulated DC output voltage and to perform natural power factor correction. An innovative THD optimizer reduces input current distortion at zero- crossing duration to improve THD performance. The PFC function is always on regardless of the PWM stage load condition to ensure that high PF can be achieved at light load...