Dual Supply Hot Swap Controller for Advanced Mezzanine Card

The LTC4223 positive voltage Hot Swap™ controller allows a board to be safely inserted and removed from a live AMC or MicroTCA backplane. It controls the main 12V supply with an external N-channel MOSFET and the 3.3V auxiliary supply with an integrated switch. The 12V output ramp rate is adjustable and includes inrush current limiting. The 12V output is also protected against short circuit faults with a fast acting current limit and a 5% accurate timed circuit breaker. The 3.3V output includes both soft start and overcurrent protection.

The LTC4223 features a current monitor output for the 12V supply, and reports fault and power-good status for both supplies. It also detects card presence and allows independent control of the 12V and auxiliary 3.3V supply outputs. The LTC4223-1 features a latch-off circuit breaker, while the LTC4223-2 provides automatic retry after a fault.

Applications

* Advanced Mezzanine Card, MicroTCA Systems

* Workstations and Server I/O

* Telecom Networks

* Allows Safe Insertion into Live AMC or MicroTCA Backplane

* Controls 12V Main and 3.3V Auxiliary Supplies

* Limits Peak Fault Current in ≤1µs

* Adjustable Current Limit with Circuit Breaker

* Integrated 0.3Ω AUX Switch

* High Side Current Sense

* Gate Drive for External N-Channel MOSFET

* Adjustable Response Time for Overcurrent Protection

* Adjustable Supply Voltage Power-Up Rate

* Thermal Shutdown Protection

* LTC4223-1: Latch Off After Fault

* LTC4223-2: Automatic Retry After Fault

* 16-Lead SSOP and 5mm × 4mm DFN Packages