MAX5977A:1V to 16V, Single-Channel, Hot-Swap Controllers with Precision Current-Sensing Output

1V to 16V, Hot-Swap Controller with Precision Current-Sense Output

The MAX5977A/MAX5977B hot-swap controllers provide complete protection for systems with a 1V to 16V single-supply voltage. During the initial insertion, the hot-swap controllers limit the inrush current from damaging the board or from shorting out the backplane. When the input voltage is above the undervoltage threshold and below the overvoltage threshold, a 5µA current source powered from the internal 5V charge pump drives the gate of an external n-channel MOSFET providing a slow turn-on response. An internal current-sense amplifier in the IC monitors the current across an external shunt resistor providing current sensing for wide input-sense voltage range. The devices provide two levels of overcurrent circuit-breaker protections: a fast-trip threshold for a fast turn-off and a lower slow-trip threshold for a delayed turn-off. Exceeding either of the overcurrent circuit-breaker thresholds will force the device into fault mode where the external n-channel MOSFET is disabled. The MAX5977 is available in two versions which provide a latched off (MAX5977A) or autoretry (MAX5977B) output when the device is in fault mode. A calibration mode allows further calibration of the integrated transconductance amplifier for production testing of the final design. The devices are offered in a 20-pin, 4mm x 4mm, TQFN-EP package and are fully specified from -40°C to +85°C.

Key Features
  • 1% Accurate Current-Sense Amplifier Output
  • Hot-Swap Monitors Operation from 1V to 16V
  • Integrated Charge Pump Fully Enhances the External n-Channel FET (VGATE = VIN + 5V)
  • VariableSpeed/BiLevel™ Fault Protection Provides Electronic Circuit-Breaker Function
  • Output Latched Off After Fault Condition (MAX5977A)
  • Autoretry After Fault Condition (MAX5977B)
  • Power-Good Indicator
  • Calibration Mode
  • Small, 20-Pin, 4mm x 4mm, TQFN-EP Package
MAX5977A, MAX5977B: Typical Operating Circuit
MAX5977A, MAX5977B: Typical Operating Circuit
Applications/Uses
  • General Hot-Swap
  • Network Switches and Routers
  • Servers
  • Storage Systems
DataSheet
titleDownload file
MAX5977A-MAX5977B Data SheetMAX5977A-MAX5977B.pdf
Parametrics
Part NumberVIN
(V)
VIN
(V)
Circuit Breaker/ Current LimitCircuit Breaker/Current Limit Threshold
(mV)
Fault Condition ControlChannelsPositive/Negative RailFeaturesPackage/PinsBudgetary
Price
minmaxSee Notes
MAX5977A116Circuit BreakerAdjustableLatched Off1PositiveOn-Board Charge Pumps to Drive External
VariableSpeed/BiLevel Current Limit
TQFN/20$1.52 @1k
MAX5977BPeriodic RetryTQFN/20$2.21 @1k
Design kits & evaluation modules
Ordering Information
Part NumberStatusRecommended ReplacementPackageTempRoHS
MAX5977AETP+ActiveTQFN,;20 pin;16.8 mm²-40°C to +85°CLead Free
MAX5977AETP+TActiveTQFN,;20 pin;16.8 mm²-40°C to +85°CLead Free
MAX5977A-MAX5977B.pdf MAX5977B
MAX5977A-MAX5977B_cn.pdf MAX5977B
Guidelines for the MAX5977’s Critical Component Placement and Routing MAX5977B
MAX5977A-MAX5977B_cn.pdf MAX5977B