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Primary Side Offline LED Controller with Active PFC
GENERAL DESCRIPTION
The PT4209 is a flicker-free PWM/analog dimmable, primary side constant current controller which can achieve high power factor in a single stage converter, targeted to applications in solid state lighting. It is designed for the flyback topology, and regulates output current accurately without the secondary feedback loop. PT4209 works in quasi-resonant mode to reduce the MOSFET switching loss. The device uses extremely low startup and low quiescent current to achieve high efficiency.