Hot Swap Controller with IC Compatible Monitoring

The LTC4215-1/LTC4215-3 Hot Swap™ controllers allow 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 on-board ADC allow for monitoring of load current, voltage and fault status.

The device features adjustable foldback current limit and a soft-start pin that sets the dI/dt of the inrush current. An I2C interface may configure the part to latch-off or automatically restart after the LTC4215-1/LTC4215-3 detect a current limit fault.

The controller has additional features to interrupt the host when a fault has occurred, provide three general purpose outputs, 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.

The LTC4215-1 has a 20μs circuit breaker filter for applications that require a fast fault response time. The LTC4215-3 has an extended 420μs circuit breaker filter for applications where supply transients may exceed 20μs.

Circuit Breaker Timeout

General Purpose Outputs

LTC4215

20μs

1

LTC4215-1

20μs

3

LTC4215-2

420μs

1

LTC4215-3

420μs

3

Applications

* Live Board Insertion

* Electronic Circuit Breakers

* Computers, Servers

* Platform Management

* Allows Safe Insertion into Live Backplane

* 8-Bit ADC Monitors Current and Voltage

* I2C/SMBus Interface

* Wide Operating Voltage Range: 2.9V to 15V

* dI/dt Controlled Soft-Start

* Circuit Breaker Timeout: 20μs (LTC4215-1) or 420μs (LTC4215-3)

* Three General Purpose Outputs