High Power Negative Voltage Hot Swap Controller with Energy Monitor

The LTC4284 negative voltage hot swap controller drives external N-channel MOSFETs to allow a board to be safely inserted and removed from a live backplane. The dual-gate, multi-mode drivers optimize the MOSFET safe operating area (SOA) for a variety of power levels. The SOA timer limits MOSFET temperature rise for reliable protection against overstresses.

An I2C interface and onboard gear-shift ADC allow monitoring of board current, voltage, power, energy, and fault status. An available single-wire broadcast mode simplifies the interface by eliminating two isolators. The included EEPROM provides black-box capturing and nonvolatile configuration of fault behavior.

Additional features respond to input UV/OV, interrupt the host when a fault has occurred, notify when output power is good, detect insertion of a board, turn off the MOSFETs if an external supply monitor fails to indicate power good within a timeout period, and auto-reboot after a programmable delay following a host commanded turn-off.

APPLICATIONS

* Telecom Infrastructure

* –48V Distributed Power Systems

* Servers and Data Centers

* Power Monitors

* Drives Two Gates for High Power Applications

* Configurable Parallel, Staged Start or Single Modes

* Protects MOSFET with SOA Timer

* Programmable 15mV to 30mV Current Limit Sense Voltage with <3.3% Accuracy and Adjustable Foldback

* 8-Bit to 16-Bit Gear-Shift ADC with 0.7% Accuracy

* Monitors Voltages, Currents, Power and Energy

* Nonvolatile Configuration and Fault Recording