MAX5938:-48V Hot-Swap Controller with VIN Step Immunity, No RSENSE, and Overvoltage Protection

The MAX5938 is a hot-swap controller for -10V to -80V rails. The MAX5938 allows circuit line cards to be safely hot-plugged into a live backplane without causing a glitch on the power supply. It integrates an adjustable circuit-breaker function requiring no RSENSE. The MAX5938 provides a controlled turn-on for circuit cards, which limits inrush current and prevents both glitches on the power-supply rail and damage to board connectors and components. Before startup, the MAX5938 performs a Load Probe™ test to detect the presence of a short-circuit condition. If a short-circuit condition does not exist, the device limits the inrush current drawn by the load by gradually turning on the external MOSFET. Once the external MOSFET is fully enhanced, the MAX5938 provides overcurrent and shortcircuit protection by monitoring the voltage drop across the RDS(ON) of the external power MOSFET. The MAX5938 integrates a 400mA fast GATE pulldown to guarantee that the external MOSFET is rapidly turned off in the event of an overcurrent or short-circuit condition. The MAX5938 also protects the system against input voltage (VIN) steps. During an input voltage step, the device limits the current drawn by the load to a safe level without shutting down the load. The device also includes ON/OFF control, selectable PGOOD output polarity, undervoltage (UV) and overvoltage (OV) protection. The device offers latched (MAX5938L) or autoretry (MAX5938A) fault management. Both the MAX5938A and MAX5938L are available in a 16-pin QSOP package and are specified for the extended (-40°C to +85°C) temperature range.

Key Features
  • -10V to -80V Operation
  • No External RSENSE Required
  • Drives Large Power MOSFETS
  • Eliminates Inrush Current Spikes During Hot Plug into Powered Backplane
  • Eliminates Inrush Current Spikes and Dropping of Load During Large VIN Steps
  • Adjustable Circuit-Breaker Threshold with Temperature Compensation
  • Circuit-Breaker Fault with Transient Rejection
  • Shorted Load Detection (Load Probe) Before Power MOSFET Turn-On
  • Programmable Load-Voltage Slew Rate Controls Inrush Current
  • ±2.4% Accuracy, Programmable Turn-On/Off Voltage (UVLO)
  • Overvoltage Fault Protection with Transient Rejection
  • Autoretry and Latched Fault Management Available
  • Low Quiescent Current (1mA)
MAX5938: Typical Operating Circuit
MAX5938: Typical Operating Circuit
Applications/Uses
  • Network Hubs, Switches, Routers
  • Network Hubs, Switches, Routers
  • Servers
  • Solid-State Circuit Breakers
  • Telecom Line Cards
DataSheet
titleDownload file
MAX5938 Data SheetMAX5938.pdf
Parametrics
Part NumberVIN
(V)
VIN
(V)
Circuit Breaker/ Current LimitCircuit Breaker/Current Limit Threshold
(mV)
Fault Condition ControlChannelsPositive/Negative RailPackage/PinsBudgetary
Price
minmaxSee Notes
MAX5938-10-80Circuit BreakerAdjustablePeriodic Retry1NegativeQSOP/16$2.85 @1k
Quality and Environmental Data
Related Products
  • MAX5900:-100V, SOT23/TDFN, Simple Swapper Hot-Swap Controllers
  • MAX5901:-100V, SOT23/TDFN, Simple Swapper Hot-Swap Controllers
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX5938AEEENo Longer AvailableMAX5938AEEE+QSOP,;16 pin;30.9 mm²-40°C to +85°CNo
MAX5938AEEE+ActiveQSOP,;16 pin;30.9 mm²-40°C to +85°CLead Free
MAX5938AEEE+TActiveQSOP,;16 pin;30.9 mm²-40°C to +85°CLead Free
MAX5938AEEE-TNo Longer AvailableMAX5938AEEE+TQSOP;16 pin-40°C to +85°CSee data sheet
MAX5938LEEENo Longer AvailableQSOP,;16 pin;30.9 mm²-40°C to +85°CNo
MAX5938LEEE+No Longer AvailableQSOP,;16 pin;30.9 mm²-40°C to +85°CLead Free
MAX5938LEEE+TNo Longer AvailableQSOP;16 pin-40°C to +85°CSee data sheet
MAX5938LEEE-TNo Longer AvailableQSOP;16 pin-40°C to +85°CSee data sheet
MAX5938.pdf MAX5938
MAX5938.pdf MAX5938
MAX5938.pdf MAX5938
MAX5938.pdf MAX5938
MAX5938.pdf MAX5938