The highly integrated FAN6921AMR 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, FAN6921AMR 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.For PWM, FAN6921AMR provides several functions to enhance power system performance: valley detection, green-mode operation, high / low line over-power compensation. Protection functions include secondary-side open-loop and over-current with auto-recovery protection, external latch triggering, adjustable over-temperature protection by the RT pin and external NTC resistor, internal over-temperature shutdown, VDD pin OVP, DET pin over-voltage for output OVP, and brown-in / out for AC input voltage UVP.The FAN6921AMR controller is available in a 16-pin, small-outline package (SOP).