SiFirst

SF5773

SSR(VI)

  • Easily Meet EPS Level 6
  • Proprietary QR-||TM Technology: Digital Anti-jitter for Audio Noise Free Operation, Digital Frequency Foldback, Digital Frequency Jittering for Better EMI
  • Less than 100mW Standby Power
  • Multi-Mode Operation for High Efficiency
  • 12.7us Maximum Duty Cycle.
  • 80KHz Maximum On Time
  • 52KHz Frequency Low Clamping in QR Mode
  • 65% Maximum Duty Cycle
  • Adaptive Slope Compensation for CCM Mode
  • Built-in soft start function
  • Built-in synchronous slope compensation
  • Constant power limiting
  • 运用

    Offline AC/DC fly-back converter for
  • AC/DC adapters
  • Open-frame SMPS
  • Set-top box power supplies
  • ATX standby power
      • SF5773 is a high performance, 2nd Generation Quasi-Resonant (QR-||TM) PWM controller for offline flyback power converter applications. The built-in proprietary QR-||TM technology with high level protection features improves the SMPS reliability and performance. 
        In SF5773, the "Digital Anti-Jitter' function can automatically select and lock a valley at a given loading, which can achieve audio noise free operation. On the other hand, the "Digital Frequency Jittering" function makes the system have superior EMI performance than conventional QR system. 
        SF5773 is a multi mode controller. When full loadings, the IC works in CCM mode or QR mode based on the AC line input . When the loading goes low, the IC enters into "Digital Frequency Foldback" mode to boost power conversion efficiency. When the output power is very small, the IC enters into burst mode and can achieve less than 100mW no load power. 
        SF5573 integrates functions and protections of Under Voltage Lockout (UVLO), VCC Over Voltage Protection (OVP), Output Over Voltage Protection (Output OVP), cycle-by-cycle Current Limiting (OCP), pins Floating Protection, Over load Protection (OLP), Soft Start , VCC Clamping, Gate Clamping, In SF5773, the protection functions are auto-recovery mode protection. 
        SF5773 is available in SOT23-6 packages.