The LTC4222CG Hot Swap™ controller allows two power paths to be safely inserted and removed from a live backplane. Using external N-channel pass transistors, board supply voltages and inrush currents are ramped up at an adjustable rate. An I2C interface and on-board ADC allows for monitoring of current, voltage and fault status for each channel.
The device features adjustable, analog, foldback current limit circuits and a Soft-Start circuit that sets the dI/dt of the inrush currents. An I2C interface may configure the part to latch off or automatically restart after the LTC4222CG detects a fault on either channel.
The controller has additional features to interrupt the host when a fault has occurred, notify when output power is good, detect insertion of a load card and power-up either automatically upon insertion or wait for an I2C command to turn on.
Feature
- Allows Safe Insertion Into a Live Backplane
- 10-Bit ADC Monitors Currents and Voltages
- I2C/SMBus Interface
- Wide Operating Voltage Range: 2.9V to 29V
- dI/dt Controlled Soft-Start
- High Side Drive for External N-Channel MOSFETs
- No External Gate Capacitors Required
- Input Overvoltage/Undervoltage Protection
- Optional Latchoff or Auto-Retry After Faults
- Alert Host After Faults
- Inrush Current Limit with Foldback
- Available in 32-Pin (5mm × 5mm) QFN and 36-Pin SSOP Packages
Applications
- Live Board Insertion
- Electronic Circuit Breakers
- Computers, Servers
- Platform Management
(Picture: Pinout)
