onsemi Quasi-Resonant Flyback Controller Flyback Controller for NCP1342 for Medium or High Power AC-DC Adapters

The ON Semiconductor Quasi-Resonant Flyback Controller, High Frequency suitable for designing high performance off−line power converters, with an integrated active X2 capacitor discharge feature, the NCP1342 can enable no load power consumption below 30 mW, the NCP1342 features a proprietary valley lockout circuitry, ensuring stable valley switching, this system works down to the 6th valley and transitions to frequency foldback mode to reduce switching losses, to ensure light load performance with high frequency designs, the NCP1342 incorporates rapid frequency foldback with minimum peak current modulation to reduce the switching frequency quickly.

Integrated High voltage start-up circuit with brownout detection
Integrated X2 capacitor discharge capability
Wide VCC range from 9 V to 28 V
28 V VCC overvoltage protection
Abnormal Overcurrent Fault Protection for Winding Short Circuit or Saturation Detection
Internal temperature shutdown
Valley switching operation with Valley Lockout for Noise free operation
Frequency Foldback with 25 kHz Minimum frequency clamp for increased efficiency at light loads
Rapid frequency foldback for fast reduction of switching
Skip Mode with Quiet Skip Technology for highest performance
Minimized current consumption for no load Power below 30 mW
Adjustable Overpower Protection
Adjustable Maximum Frequency Clamp
Fault Pin for Severe Fault Conditions, NTC Compatible for OTP