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SD4954B
POWERED DEVICE (PD) AND DC/DC CONTROLLER COMPATIBLE WITH IEEE 802.3AF STANDARD

SD4954B is an Ethernet powered device and DC/DC controller IC compatible with IEEE 802.3af standard. It provides powered devices (PD) with functions of detection, classification and inrush current limit.

SD4954B integrates a 100V power MOSFET with on-resistance of 0.6Ω, and features built-in current limit, undervoltage protection and over temperature protection.

The DC/DC controller integrates a 200V power MOSFET with SSR control. It is suitable for Flyback and buck topology, providing accurate CV control loop. It features high system efficiency and good EMI characteristic. 


Main feature
  • PD controller

  • IEEE 802.3af Compliant

  • 100V 0.6Ω On-chip MOSFET  

  • Undervoltage lockout

  • Over temperature protection 

  • 180mA inrush current limit

  • 850mA operating current

  • Fault automatic retry

  • DC/DC controller 

  • Fixed switching frequency control

  • Internal error amplifier

  • Leading-Edge Blanking

  • Maximum duty cycle limit

  • No-load sleep mode

  • Soft startup

  • Internal 200V MOSFET

  • VCC over voltage protection

  • VCC undervoltage lockout

  • Over temperature protection

  • Over load protection

  • Cycle-by-cycle current limit


Ordering Information
Product Name Package form Marking Hazardous Substance Control Packing Type Remarks
SD4954BTR SOP-16-225-1.27 SD4954B Halogen free Tape & Reel
SD4954B SOP-16-225-1.27 SD4954B Halogen free Tube
Block Diagram

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