GENERAL DESCRIPTION

The ADM1073 is a full-feature, negative voltage, hot swap controller that allows boards to be safely inserted and removed from a live −48 V backplane. The part provides precise and robust current limiting, and protection against both transient and nontransient short circuits in overvoltage and undervoltage conditions. The ADM1073 can operate from a negative voltage of −18 V to −80 V and can tolerate transient voltages of up to −200 V.

FEATURES

Precision inrush linear current limit

Soft start inrush current limit profiling

Precision maximum on-time in current limit

Maximum on-time modulated by FET drain voltage for

additional SOA protection

Adjustable PWM retry scheme and multiple device cascading

capability for charging large capacitive loads

Limited number of PWM cycles for FET SOA protection under

short circuit condition

Ability to configure device as continuous autoretry with a

5-second cooling period

Shunt regulator topology to allow very large transient input

supplies

Separate UV and OV pins for programming allowable input

supply window

Programmable OV hysteresis using current source into pin

when supply is high

Programmable UV hysteresis using current sink from pin

when supply is low

PWRGD output indicates when capacitor charging complete

SPLYGD output indicates when supply is within

valid window

LATCHED output indicates the end of the retry cycle before

load capacitance is charged

SHDN input for user-commanded shutdown

RESTART input for user-triggered 5-second shutdown and

autorestart— virtual card reseat

APPLICATIONS

Central office switching

Telecommunication and data communication equipment

−48 V distributed power systems

Negative power supply control

High availability servers

−48 V power supply modules

Disk arrays