The LTC4280 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 allow for monitoring of load current, voltage and fault status. The device features adjustable analog foldback current limit and a FILTER pin which configures the time spent in overcurrent before declaring a fault. An I2C interface may configure the part to latch off or automatically restart after the LTC4280 detects a current limit fault. 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.
