Features

• Order Custom Programmed Parts
• Allows Safe Board Insertion Into Live Backplane
• 12-/16-Bit ADC with ±0.7% Total Unadjusted Error
• Monitors Current, Voltage, Power and Energy
• Internal EEPROM for Nonvolatile Configuration
• Wide Operating Voltage Range: 2.9V to 33V
• I²C/SMBus Digital Interface (Coexists with PMBus Devices)
• 12V Gate Drive for Lower MOSFET R_DS(ON)
• Programmable Current Limit with 2% Accuracy
• MOSFET Power Limiting with Current Foldback
• Continuously Monitors MOSFET Health
• Stores Minimum and Maximum Measurements
• Alerts When Alarm Thresholds Exceeded
• Reboots on I²C Command
• Input Overvoltage/Undervoltage Protection
• Three General Purpose Input/Outputs
• Internal ±5% or External Timebases
• 28-Pin 4mm × 5mm QFN Package

Typical Application

Description

The LTC®4281 Hot Swap controller allows a board to be safely inserted and removed from a live backplane. Using an external N-channel pass transistor, board supply voltage and inrush current are ramped up at an adjustable rate. An I²C interface and onboard ADC allows for monitoring of board current, voltage, power, energy and fault status.

The device features analog foldback current limiting to limit the MOSFET power to a constant value. A wide input voltage operating range comfortably allows applications from 2.9V to 33V.

The LTC4281 is well suited to high power applications because the precise monitoring capability and accurate current limiting reduce the extremes in which both loads and power supplies must safely operate. Non-volatile configuration allows for flexibility in the autonomous generation of alerts and response to faults.