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onsemi NCP1341 Quasi-Resonant Controllers

onsemi NCP1341 Quasi-Resonant Controllers are ideal for designing high-performance off-line power converters. The controllers feature an integrated active X2 capacitor-discharge feature. The NCP1341 can enable no-load power consumption below 30mW, and 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. The NCP1341 enters quiet-skip mode as the load decreases to manage power delivery while minimizing acoustic noise.

Features

  • Integrated high-voltage startup circuit with brownout detection
  • Integrated x2 capacitor-discharge capability
  • Wide VCC range from 9V to 28V
  • 28V 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 25khz minimum frequency clamp for increased efficiency at light loads
  • Skip mode with quiet-skip technology for highest performance during light loads
  • Minimized current consumption for no-load power below 30mw
  • Frequency jittering for reduced EMI signature
  • Latching or auto-recovery timer-based overload protection
  • Adjustable overpower protection (OPP)
  • Fixed or adjustable maximum frequency clamp
  • Fault pin for severe fault conditions, NTC compatible for OTP (9-pin version only)
  • 4ms soft-start timer

Block Diagram

Block Diagram - onsemi NCP1341 Quasi-Resonant Controllers
Published: 2021-03-23 | Updated: 2022-03-11