DESCRIPTION
The LT®1640AL/LT1640AH are 8-pin, negative voltage Hot Swap™ controllers that allow 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 (LT1640AL) or PWRGD (LT1640AH) signal can
be used to directly enable a power module. The LT1640AL is designed for modules with a low enable input and the LT1640AH for modules with a high enable input.

FEATURES
■ Allows Safe Board Insertion and Removal from a Live – 48V Backplane
■ Operates from –10V to – 80V
■ Programmable Inrush Current
■ Allows 50mA of Reverse Drain Pin Current
■ Programmable Electronic Circuit Breaker
■ Programmable Overvoltage Protection
■ Programmable Undervoltage Lockout
■ Power Good Control Output