NCP1651

NCP1651 Single Stage Power Factor Controller The NCP1651 is an active, power factor correction controller that can operate over a wide range of input voltages. It is designed for 50/60 Hz power systems. It is a fixed frequency controller that can operate in continuous or discontinuous conduction modes. The NCP1651 provides a low cost, low component count solution for isolated AC−DC converters with mid−high output voltage requirements. The NCP1651 eases the task of meeting the IEC1000−3−2 harmonic requirements for converters in the range of 50 W − 250 W. The NCP1651 drives a flyback converter topology to operate in continuous/discontinuous mode and programs the average input current to follow the line voltage in order to provide unity power factor. By using average current mode control CCM algorithm, the NCP1651 can help provide excellent power factor while limiting the peak primary current. Also, the fixed frequency operation eases the input filter design. The NCP1651 uses a proprietary multiplier design that allows for much more accurate operation than with conventional analog multipliers. Features Fixed Frequency Operation Average Current Mode PWM Internal High Voltage Startup Circuit Continuous or Discontinuous Mode Operation High Accuracy Multiplier Overtemperature Shutdown External Shutdown Undervoltage Lockout Low Cost/Parts Count Solution Ramp Compensation Does Not Affect Oscillator Accuracy This is a Pb−Free Device Typical Applications High Cu...