LT1641 pdf datasheet (Positive

The LT?1641-1/LT1641-2 are 8-pin Hot SwapTM controllers
that allow a board to be safely inserted and removed
from a live backplane. Using an external N-channel pass
transistor, the board supply voltage can be ramped up at
a programmable rate. A high side switch driver controls an
N-channel gate for supply voltages ranging from 9V to
80V.
The chips feature a programmable analog foldback current
limit circuit. If the chips remain in current limit for
more than a programmable time, the N-channel pass
transistor is either latched off (LT1641-1) or is set to
automatically restart after a time-out delay (LT1641-2).
The PWRGD output indicates when the output voltage,
sensed by the FB pin, is within tolerance. The ON pin
provides programmable undervoltage lockout.
The LT1641-1/LT1641-2 are available in the 8-lead SO
package.