DescripTion
The LTC®4228 offers ideal diode and Hot Swap™ functions for two power rails by controlling two external N-channel MOSFETs in each rail. MOSFETs acting as ideal diodes replace two high power Schottky diodes and the associated heat sinks, saving power and board area. Hot Swap control MOSFETs allow boards to be safely inserted and removed from a live backplane by limiting inrush current. The supply output is also protected against short-circuit faults with a fast acting current limit and internal timed circuit breaker.

FEATUREs
■ Power Path and Inrush Current Control for
   Redundant Supplies
■ Low Loss Replacement for Power Schottky Diodes
■ Protects Output Voltage from Input Brownouts
■ Allows Safe Hot Swapping from a Live Backplane
■ 2.9V to 18V Operating Range
■ Controls N-Channel MOSFETs
■ Limits Peak Fault Current in ≤1µs
■ Adjustable Current Limit with Circuit Breaker
■ Adjustable Current Limit Fault Delay
■ Smooth Switchover without Oscillation
■ 0.5µs Ideal Diode Turn-On and Turn-Off Time
■ Status, Fault and Power Good Outputs
■ LTC4228-1: Latch Off After Fault
■ LTC4228-2: Automatic Retry After Fault
■ 28-Lead 4mm × 5mm QFN and SSOP Packages

APPLICATIONs
■ Redundant Power Supplies
■ MicroTCA Systems and Servers
■ Telecom Networks
■ Power Prioritizer