Negative Voltage Hot Swap Controller

The LT1640L/LT1640H is an 8-pin, negative voltage Hot Swap™ controller that allows a board to be safely inserted and removed from a live backplane. Inrush current is limited to a programmable value by controlling the gate voltage of an external N-channel pass transistor. The pass transistor is turned off if the input voltage is less than the programmable undervoltage threshold or greater than the overvoltage threshold. A programmable electronic circuit breaker protects the system against shorts. The PWRGD (LTC1640L) or PWRGD (LTC1640H) signal can be used to directly enable a power module. The LT1640L is designed for modules with a low enable input and the LT1640H for modules with a high enable input.

The LT1640L/LT1640H is available in 8-pin PDIP and SO packages.

Applications

* Central Office Switching

* –48V Distributed Power Systems

* Negative Power Supply Control

* Allows Safe Board Insertion and Removal from a Live –48V Backplane

* Operates from –10V to –80V

* Programmable Inrush Current

* Programmable Electronic Circuit Breaker

* Programmable Overvoltage Protection

* Programmable Undervoltage Lockout

* Power Good Control Output