-48V Hot-Swap Controller with External RSENSE

Hot-Swap Controller with External RSENSE Well-Suited for -48V Power Systems

Please check latest availability status for a specific part variant.


The MAX5920A/MAX5920B are hot-swap controllers that allow a circuit card to be safely hot plugged into a live backplane. The MAX5920A/MAX5920B operate from -20V to -80V and are well-suited for -48V power systems. These devices are pin and function compatible with the LT4250 and pin compatible with the LT1640.

The MAX5920A/MAX5920B provide a controlled turn-on to circuit cards preventing glitches on the power-supply rail and damage to board connectors and components. The MAX5920A/MAX5920B provide undervoltage, overvoltage, and overcurrent protection. These devices ensure the input voltage is stable and within tolerance before applying power to the load.

Both the MAX5920A and MAX5920B protect a system against overcurrent and short-circuit conditions by turning off the external MOSFET in the event of a fault condition. The MAX5920A/MAX5920B also provide protection against input voltage steps. During an input voltage step, the MAX5920A/MAX5920B limit the current drawn by the load to a safe level without turning off power to the load.

Both devices feature an open-drain power-good status output (active-low PWRGD for the MAX5920A or PWRGD for the MAX5920B) that can be used to enable downstream converters. A built-in thermal-shutdown feature is also included to protect the external MOSFET in case of overheating.

The MAX5920A/MAX5920B are available in an 8-pin SO package. Both devices are specified for the extended -40°C to +85°C temperature range.
MAX5920: Typical Operating Circuit MAX5920: Typical Operating Circuit Enlarge+

Key Features

  • Allows Safe Board Insertion and Removal from a Live -48V Backplane
  • Pin- and Function-Compatible with LT4250L (MAX5920A)
  • Pin-Compatible with LT1640L (MAX5920A)
  • Pin- and Function-Compatible with LT4250H (MAX5920B)
  • Pin-Compatible with LT1640H (MAX5920B)
  • Circuit-Breaker Immunity to Input Voltage Steps and Current Spikes
  • Withstands -100V Input Transients with No External Components
  • Programmable Inrush and Short-Circuit Current Limits
  • Operates from -20V to -80V
  • Programmable Overvoltage Protection
  • Programmable Undervoltage Lockout
  • Powers Up into a Shorted Load
  • Power-Good Control Output
  • Thermal Shutdown Protects External MOSFET


  • Base-Station Line Cards
  • Central-Office Line Cards
  • Network Routers and Switches
  • Server Line Cards
  • Telecom Line Cards
Part NumberVIN
Circuit Breaker/ Current LimitCircuit Breaker/Current Limit Threshold
Fault Condition ControlChannelsPositive/Negative RailFeaturesPackage/PinsBudgetary
minmaxSee Notes
MAX5920 -20-80Current Limit50Latched Off1NegativeUndervoltage/Overvoltage Protection
SOIC (N)/8
$2.53 @1k
See All Hot Swap Controllers (49)
Pricing Notes:
This pricing is BUDGETARY, for comparing similar parts. Prices are in U.S. dollars and subject to change. Quantity pricing may vary substantially and international prices may differ due to local duties, taxes, fees, and exchange rates. For volume-specific and version-specific prices and delivery, please see the price and availability page or contact an authorized distributor.

Technical Documents

App Note 4033 Programmable Fan Controllers

Quality and Environmental Data

Product Reliability Reports: MAX5920.pdf 
Lead-Free Package Tin (Sn) Whisker Reports

CAD Symbols and Footprints

  • MAX5920AESA
  • MAX5920AESA+
  • MAX5920AESA+T
  • MAX5920AESA-T
  • MAX5920BESA
  • MAX5920BESA+
  • MAX5920BESA+T
  • MAX5920BESA-T
  • MAX5920CESA
  • MAX5920CESA+
  • MAX5920CESA+T
  • MAX5920CESA-T
  • MAX5920DESA
  • MAX5920DESA-T
  • MAX5920EESA
  • MAX5920EESA-T
  • MAX5920FESA
  • MAX5920FESA-T
  • Device   Fab Process   Technology   Sample size   Rejects   FIT at 25°C   FIT at 55°C  

    Note : The failure rates are summarized by technology and mapped to the associated material part numbers. The failure rates are highly dependent on the number of units tested.

    Quality Management System >
    Environmental Management System >


    Related Resources

    Type ID PDF Title
    App Note 4033 Programmable Fan Controllers