SiFirst

SF5873

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
  • Proprietary HV-mWTM to Achieve Less than 50mW Standby Power
  • Multi-Mode Operation for High Efficiency
  • 12.7us Maximum Duty Cycle.
  • 80KHz Maximum On Time
  • 53KHz Frequency Low Clamping in QR Mode
  • 65% Maximum Duty Cycle
  • Adaptive Slope Compensation for CCM Mode
  • Built-in 600V Power MOSEFT
  • Constant power limiting
  • VDD UVLO, OVP & Clamp
  • 运用

    Offline AC/DC fly-back converter for
  • AC/DC adapters
  • Open-frame SMPS
  • Set-top box power supplies
  • ATX standby power
      • SF5873 is a high performance, 2nd Generation Quasi-Resonant (QR-IITM) PWM controller for offline flyback power converter applications. The built-in proprietary HV-mWTM technology and QR-IITM technology with high level protection features can improve the SMPS reliability and performance.  
        In SF5873, 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.  
        SF5873 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 50mW no load power. 
        SF5873 integrates functions and protections of Under Voltage Lockout (UVLO), VDD Over Voltage Protection (VDD OVP), Output Over Voltage Protection (Output OVP), Cycle-by-cycle Current Limiting (OCP), Pin Floating Protection, Over Load Protection (OLP), Soft Start, VCC Clamping, Gate Clamping, etc. In SF5873, VDD OVP and Output OVP are latch mode protections, the other protections are auto-recovery mode. 
        SF5873 is available in SOP8 package.