Integrated Critical-Mode PFC and Quasi-Resonant Current-Mode PWM Lightning Controller
FL7921R
Description The highly integrated FL7921R combines a Power Factor
Correction (PFC) controller and a Quasi−Resonant PWM controller.
Integration provides cost effect design and allows for fewer external components.
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 condition.
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